1.
John Henry (album)
–
John Henry is the fifth studio album by American alternative rock group They Might Be Giants. It is the first album by They Might Be Giants to include a band arrangement. John Henry is TMBGs longest record and was the bands highest-charting adult album, having peaked at #61 on the Billboard 200, until 2011s Join Us, in 2013, the album was reissued across a double LP by Asbestos Records. The lyrics to the song AKA Driver refer to a NyQuil driver, John Flansburgh offered an explanation of the legal issue with the inclusion of a brand name, It was a brief education for us in the difference between protected speech and trademark infringement. According to our lawyer you can say pretty much anything in a song about a product, however when you title a song after a trademarked product and then start selling your recording you run the risk of the trademark holder suing you for infringing on their trademark. To make matters tougher on ol NyQuil Driver, trademark holders are compelled by the law to protect their trademark or they run the risk of their product name falling into the public domain. I Should Be Allowed to Think excerpts the first line of the poem Howl by Allen Ginsberg, the song is also, according to its author, John Linnell, an example of the use of an unreliable narrator. Meet James Ensor refers to an eccentric Belgian expressionist painter whose works excited John Flansburgh, all tracks written by They Might Be Giants, except where noted
John Henry (album)
–
John Henry
2.
Neptunea angulata
–
†Neptunea angulata is an extinct species of large fossil sea snail, a marine gastropod mollusk in the family Buccinidae. There is some confusion concerning the nomenclature of this extinct taxon, the species was formerly known as Neptunea contraria. This is, however, the name of an extant species. This has been clarified by Nelson & Pain,1986
Neptunea angulata
–
Neptunea angulata
Neptunea angulata
–
Shells of Neptunea angulata
3.
Helix pomatia
–
In the English language it is called by the French name escargot when used in cooking. Although this species is prized as a food it is difficult to cultivate. Distribution of Helix pomatia includes, Southeastern and central Europe, Germany – Listed as a protected species in annex 1 of the Bundesartenschutzverordnung. Austria Czech Republic – least concern species, Its conservation status in 2004–2006 is favourable in the report for the European commission in accordance with the Habitats Directive, poland Slovakia Hungary Romania In southwestern Bulgaria up to an altitude of more than 1600 m. Northern and central Balkans Slovenia Croatia Bosnia & Herzegovina Serbia Republic Of Macedonia Western Europe, Great Britain, in the west and its common name in the UK is Roman snail because it was introduced to the island by the Romans during the Roman period. In England only, the Roman snail is a species under the Wildlife and Countryside Act 1981, making it illegal to kill, injure. Central France Belgium Netherlands Switzerland Northern Europe, Denmark – Listed as a protected species, Southern Sweden Norway Finland In central and southern parts of Sweden, Norway and Finland, isolated and relatively small populations occur. It is not native to countries, but is likely to have been imported by monks from Southern Europe during medieval times. The shell has five to six whorls, the apertural margin is white and slightly reflected in adult snails. The umbilicus is narrow and partly covered by the columellar margin. The width of the shell is 30–50 mm, the height of the shell is 30–45 mm. In southeastern Europe, H. pomatia lives in forests, open habitats, gardens, vineyards, especially along rivers, in central Europe, it occurs in open forests and shrubland on calcareous substrate. It prefers high humidity and lower temperatures, and needs loose soil for burrowing to hibernate and it lives up to 2100 m above sea level in the Alps, but usually below 2000 m. In the south of England, it is restricted to undisturbed grassy or bushy wastelands, usually not in gardens, it has a low reproduction rate, average distance of migration reaches 3. 5–6.0 m. Reproduction in central Europe begins at the end of May, reproduction Eggs are laid in June and July, in clutches of 40–65 eggs. The size of the egg is 5. 5–6.5 mm or 8.6 ×7.2 mm. Juveniles hatch after three to four weeks, and may consume their siblings under unfavourable climate conditions, maturity is reached after two to five years. The life span is up to 20 years, ten-year-old individuals are probably not uncommon in natural populations. The maximum lifespan is 35 years, during estivation or hibernation, this species creates a calcareous epiphragm to seal the opening of the shell
Helix pomatia
–
Helix pomatia
Helix pomatia
–
Cooked snails are called
escargot
Helix pomatia
–
View of a
shell of Helix pomatia
Helix pomatia
–
Helix pomatia (the larger snail) laying eggs)
4.
Umbilicus (mollusk)
–
The umbilicus of a shell is the axially aligned, hollow cone-shaped space within the whorls of a coiled mollusc shell. The word is applied to the depressed central area on the planispiral coiled shells of Nautilus species. The spirally coiled whorls of gastropod shells frequently connect to other by their inner sides. This results in a more or less solid central axial pillar, the more intimate the contact between the concave side of the whorls is, the more solid the columella becomes. On the other hand, if this connection is less intense and this opening is known as the umbilicus. Another way of characterizing the umbilicus in gastropods is as the hole around which the surface of the shell is coiled. In species with a wide, open umbilicus, such as the heath snail, an umbilicus can vary from very narrow and punctured, as found in Petasina unidentata, to wide and shallow, such as the deep and wide depression in the rounded snail. Shells with a conspicuous umbilicus are always orthostylic, i. e. they have a poorly developed columella, a phaneromphalous shell has an open umbilicus. A cryptomphalous shell has the opening of the umbilicus completely plugged, dictionary definition Shows the position of the umbilicus on an apple snail
Umbilicus (mollusk)
–
The umbilicus is clearly visible on the underside of the left shell of these three shells of
Xerolenta obvia
Umbilicus (mollusk)
–
An
X-ray image of a shell of a marine triton snail,
Charonia, showing the central columella, reaching from the top of the image (the apex of the shell) to the bottom (the
siphonal canal)
Umbilicus (mollusk)
–
The wide and deep umbilicus of
Cittarium pica is easily visible on the underside of the shell.
Umbilicus (mollusk)
–
The shell of
Neverita josephinia has an umbilical callus which almost completely fills the umbilicus, leaving only a groove, and a chink on one side.
5.
Plait (gastropod)
–
A plait is an anatomical feature which is present the shells of some snails, or gastropods. This sculpture occurs often in the shells of marine gastropod mollusks in the clade Neogastropoda, plaits are folds on the columella at the center of the shell. The columella is the structure around which the whorls of a coiled gastropod shell are coiled. Powell A W B, New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 ISBN 0-00-216906-1
Plait (gastropod)
–
The
aperture of the shell of
Alcithoe swainsoni shows five plaits on the
columella, four strong and one weak
6.
Aperture (mollusc)
–
The aperture is an opening in certain kinds of mollusc shells, it is the main opening of the shell, where the head-foot part of the body of the animal emerges for locomotion, feeding, etc. The term aperture is used for the opening in gastropod shells, scaphopod shells. The word is not used to describe bivalve shells, where an opening between the two shell valves in the closed position is usually called a gape. Scaphopod shells are tubular, and thus they have two openings, a main anterior aperture and a smaller posterior aperture, in some prosobranch gastropods, the aperture of the shell can be closed, and even completely sealed, with a sort of door or operculum. The aperture of many snail shells is more or less round, rounded and this shape usually corresponds roughly to the cross-section of the body whorl of the shell. The aperture of a snail shell can have other forms, semicircular. In some gastropods, the aperture is narrowed by protruding plaits, the growth of the shell is provided for by non-continuous addition of minute layers to the aperture margin from the mantle border, the principal agent in the secretion of the shell. The margin of the aperture is sometimes continuous or entire, or becomes continuous in the adult, very frequently it is interrupted, the siphonal notch is situated at the top. The columellar wall with the lip, the wall next to the columella. The siphonal canal is situated at its base, the palatal wall, the outer free wall of the final whorl of the shell. The aperture is descending or deflected, when it does not follow the spiral of the shell, sometimes it departs from contact with the preceding whorl. Consequently, there is no siphonal canal but simply an opening for respiration and these teeth may be outer lip teeth, columellar teeth or parietal teeth. Folds or plicae are named by their position in the aperture, as follows
Aperture (mollusc)
–
Three views of a
shell of
Norelona pyrenaica with the apertural view in the center
Aperture (mollusc)
–
A shell of
Semicassis pyrum, which has a large aperture and a pronounced
parietal callus
Aperture (mollusc)
–
Conus betulinus has a long and narrow aperture.
Aperture (mollusc)
–
Indrella ampulla has an oval aperture.
7.
Columella (gastropod)
–
The columella or pillar is a central anatomical feature of a coiled snail shell, a gastropod shell. The columella is often clearly visible as a structure when the shell is broken, sliced in half vertically. The columella runs from the apex of the shell to the midpoint of the undersurface of the shell, or the tip of the siphonal canal in those shells which have a siphonal canal. If a snail shell is visualized as a cone of shelly material which is wrapped around a central axis, in the case of shells that have an umbilicus, the columella is a hollow structure. The columella of some groups of shells can have a number of plications or folds. These folds can be wide or narrow, prominent or subtle and these features of the columella are often useful in identifying the family, genus, or species of the gastropod. The surface of the columella is called the columellar wall, the columellar callus is a smooth, calcareous thickening, secreted by the mantle, extending over the columellar area. The columellar lip, the part of the columella, is the lower part of the inner lip and is situated near the axis of coiling. A columellar tooth is a projection on the inner lip of a columella in the direction of the aperture. The soft parts of the body of the gastropod are held in place in the shell by the columellar muscles. These muscles are attached strongly to the columella itself not just far up in the apex of the shell but also by a long and narrow attachment over the length of a full whorl along the columella. The columellar muscle passes underneath the mantle, greatly thickening the body wall, the columellar muscles are contracted when the animal needs to withdraw the foot, head, and other soft parts into the shell for protection from drying out, and from predators. During these contractions the operculum and shell are approximated, and the animal is withdrawn within the latter, the columellar muscles are equally used to bring the soft body out of the shell. During protraction and retraction, the twists, shortens or elongates. In very large such as the Queen Conch, Eustrombus gigas, once the columellar muscles are cut with a knife. Conch fishermen in the Caribbean Sea break a hole in the spire of the shell, cut the columellar muscles. Often the fishermen dump the empty back into the sea again. Columella listed in a glossary Another glossary A scholarly article on columellar muscles and columellar folds photo of cross section through shells
Columella (gastropod)
–
An
X-ray image of a shell of a marine "triton" snail,
Charonia, showing the slightly sinuous line of the central columella, reaching from the top of the image (the apex of the shell) to the bottom (the siphonal canal)
Columella (gastropod)
–
Shell of Helix pomatia with a part of shell removed; (4) the columella
8.
Suture (gastropod)
–
In anatomy, a suture is a fairly rigid joint between two or more hard elements of an organism, with or without significant overlap of the elements. Sutures are found in the skeletons or exoskeletons of a range of animals. Sutures are found in animals with hard parts from the Cambrian period to the present day, sutures were and are formed by several different methods, and they exist between hard parts that are made from several different materials. The skeletons of vertebrate animals are made of bone, in which the main ingredient is calcium phosphate. The skulls of most vertebrates consist of sets of plates held together by cranial sutures. These sutures are held mainly by Sharpeys fibers which grow from each bone into the adjoining one. The shells of most molluscs are made of carbonate, and of conchiolin. For more information, see Mollusc shell, in cephalopod mollusks which have external shells, the shell is divided into compartments by septa. The septa are joined to the shell by sutures formed by repeated invagination. The sutures are visible from the outside and often form complex, nearly all snail shells can be visualized as a tube of increasing diameter, closed at the small end, and spirally wrapped around a central axis. For more information, see Gastropod shell, each complete rotation of this spirally-arranged tube is called a whorl. The whorls of a shell usually overlap one another, forming a spire. Where the whorls overlap, there is usually a clear indentation and this indentation forms a visible line, which is continuous and reaches from the apex of the shell to the aperture, this line is the suture. Details of the suture are often useful in discriminating one species from another, for example, when an angulation of the whorls occurs, the space between it and the suture above it constitutes the area known as the shoulder of the shell. The shoulder angle may be simple or keeled, an may sometimes have nodes or spines A trilobites carapace consisted of calcite, in many species the cephalon had sutures running from back to front round the outside edges of the eyes. These sutures divided the cephalon into 3 pieces
Suture (gastropod)
–
A variety of ammonite forms, from
Ernst Haeckel 's 1904 Kunstformen der Natur (Artforms of Nature).
Suture (gastropod)
–
Side view of the skull. The wavy lines are
cranial sutures.
Suture (gastropod)
–
Two shells of
Papillifera bidens, scale bar is in mm. These shells have 10 or 11
whorls and thus a very long suture, with an unusual
sculpture of regularly placed
papules along the suture itself.
9.
Arianta arbustorum
–
Arianta arbustorum is a medium-sized species of land snail, sometimes known as the copse snail, a terrestrial pulmonate gastropod mollusk in the family Helicidae. One of the most frequent species of snails in Switzerland, can be very abundant. In Finland, it has become so common in the Porvoo region east of Helsinki, estonia Latvia scattered to Serbia Bulgaria It is rare in Bulgaria. Therefore, it has suggested that this species be given top national quarantine significance in the USA. The shell has 5-5.5 convex whorls with deep suture, the last whorl is slightly descending near the aperture. The aperture is with prominent white lip inside, umbilicus is entirely covered by the reflected columellar margin. The width of the shell is 18–25 mm, the height of the shell is 12–22 mm. Arianta arbustorum lives in forests and open habitats of any kind and it lives also in disturbed habitats. It may locally tolerate non-calcareous substrate, in north Scotland also on sandhills, in the Alps up to 2700 m, in Britain 1200 m, in Bulgaria 1500 m. It feeds on herbs, dead animals and faeces. If snails hatched more than 50 m distant from other, they are considered isolated since they would not move more than 25 m, usually they move about 7–12 m in a year. This species of snail makes and uses love darts during mating. Reproduction is usually after copulation, but self-fertilization is also possible, the size of the egg is 3.2 mm. Maturity is reached after 2–4 years. The maximum age up to 14 years, angiostrongylus vasorum has successfully experimentally infected this snail. This article incorporates public domain text from the reference, Arianta arbustorum at Animalbase taxonomy, short description, distribution, biology, status, images Arianta arbustorum images at Encyclopedia of Life Arianta arbustorum. Baur, Anette, Baur, Bruno Interpopulation variation in the prevalence and intensity of parasitic infection in the land snail Arianta arbustorum, Invertebrate Biology, Vol.124 Issue 3. Baur, Bruno & Locher Rolf Sperm allocation in the simultaneously hermaphroditic land snail Arianta arbustorum, oct98, Vol.56 Issue 4, p839. Baur, Bruno Patterns of dispersion, density and dispersal in alpine populations of the land snail Arianta arbustorum, mai 1986, Vol.9 Issue 2, p117-125
Arianta arbustorum
–
Arianta arbustorum
Arianta arbustorum
–
apertural view of the
shell of Arianta arbustorum (top left); lateral view (top right); apical view (bottom left) and umbilical view (bottom right)
10.
Mollusc shell
–
Not all shelled molluscs live in the sea, many live on the land and in freshwater. Within some species of molluscs, there is often a degree of variation in the exact shape, pattern, ornamentation. A mollusc shell is formed, repaired and maintained by a part of the called the mantle. Any injuries to or abnormal conditions of the mantle are reflected in the shape and form. When the animal encounters harsh conditions that limit its food supply, or otherwise cause it to become dormant for a while, when conditions improve again and the mantle resumes its task, a growth line is produced. The mantle edge secretes a shell which has two components, the shell formation requires certain biological machinery. This caps off the space, which is bounded on its other surfaces by the existing shell. The accumulation of ions is driven by ion pumps packed within the calcifying epithelium, the organic matrix forms the scaffold that directs crystallization, and the deposition and rate of crystals is also controlled by hormones produced by the mollusc. Nucleation is endoepithelial in Neopilina and Nautilus, but exoepithelial in the bivalves, the formation of the shell involves a number of genes and transcription factors. On the whole, the factors and signalling genes are deeply conserved. Engrailed serves to demark the edge of the field, dpp controls the shape of the shell. In gastropod embryos, Hox1 is expressed where the shell is being accreted, perlucin operates in association with Perlustrin, a smaller relative of lustrin A, a protein responsible for the elasticity of organic layers that makes nacre so resistant to cracking. Lustrin A bears remarkable structural similarity to the involved in mineralization in diatoms – even though diatoms use silica, not calcite. The shell at another first giant clam, the characterizations of the second elasticity sheels. The second responsibles id makes by commons however no association has been observed between Hox genes and cephalopod shell formation, a wide range of enzymes are expressed during the formation of the shell, including carbonic anhydrase, alkaline phosphatase, and DOPA-oxidase /peroxidase. The shell-secreting area is differentiated very early in embryonic development, an area of the ectoderm thickens, then invaginates to become a shell gland. The gland subsequently evaginates in molluscs that produce an external shell, a wide range of enzymes are expressed during the formation of the shell, including carbonic anhydrase, alkaline phosphatase, and DOPA-oxidase /peroxidase. The form of the shell is constrained by the organisms ecology
Mollusc shell
–
Closed and open shells of a marine
bivalve,
Petricola pholadiformis. A
bivalve shell is composed of two hinged valves which are joined by a ligament.
Mollusc shell
–
Four views of a shell of the
land snail Arianta arbustorum
Mollusc shell
–
The
giant clam (Tridacna gigas) is the largest extant species of bivalve. The mantle is visible between the open valves
Mollusc shell
–
The chiton
Tonicella lineata, anterior end towards the right
11.
Gastropoda
–
The Gastropoda or gastropods, more commonly known as snails and slugs, are a large taxonomic class within the phylum Mollusca. The class Gastropoda includes snails and slugs of all kinds and all sizes from microscopic to large, there are many thousands of species of sea snails and sea slugs, as well as freshwater snails, freshwater limpets, land snails and land slugs. The class Gastropoda contains a vast total of named species, second only to the insects in overall number, the fossil history of this class goes back to the Late Cambrian. There are 611 families of known, of which 202 are extinct. Gastropoda are a part of the phylum Mollusca, and are the most highly diversified class in the phylum, with 65,000 to 80,000 living snail. The anatomy, behavior, feeding, and reproductive adaptations of gastropods vary significantly from one clade or group to another, therefore, it is difficult to state many generalities for all gastropods. The class Gastropoda has an extraordinary diversification of habitats and those gastropods without a shell, and those with only a very reduced or internal shell, are usually known as slugs, those with a shell into which they cannot withdraw are termed limpets. In a number of families of species, such as all the various limpets, the shell is coiled only in the larval stage, in the scientific literature, gastropods were described under gasteropodes by Georges Cuvier in 1795. Cuvier chose gastropod by derivation from the Ancient Greek words γαστήρ stomach, the earlier name univalve means one valve or shell, in contrast to bivalve applied to mollusks such as clams and meaning that those animals possess two valves or shells. At all taxonomic levels, gastropods are second only to the insects in terms of their diversity, Gastropods have the greatest numbers of named mollusc species. However, estimates of the number of gastropod species vary widely. The number of species can be ascertained from estimates of the number of described species of Mollusca with accepted names. But an estimate of the number of Mollusca, including undescribed species, is about 240,000 species. The estimate of 85,000 molluscs includes 24,000 described species of terrestrial gastropods, different estimates for aquatic gastropods give about 30,000 species of marine gastropods, and about 5,000 species of freshwater and brackish gastropods. The total number of living species of snails is about 4,000. There are 444 recently extinct species of gastropods,18 species that are now extinct in the wild and 69 possibly extinct species, the number of prehistoric species of gastropods is at least 15,000 species. Some of the familiar and better-known gastropods are terrestrial gastropods and some live in freshwater. Gastropods have a distribution from the near Arctic and Antarctic zones to the tropics
Gastropoda
Gastropoda
–
The upper pair of
tentacles on the head of Helix pomatia have eye spots, but the main sensory organs of the snail are sensory receptors for
olfaction, situated in the
epithelium of the tentacles.
Gastropoda
–
A 9-hour-old
trochophore of
Haliotis asinina sf -
shell field
12.
Snail
–
Snail is a common name that is applied most often to land snails, terrestrial pulmonate gastropod molluscs. However, the common name snail is also applied to most of the members of the molluscan class Gastropoda that have a shell that is large enough for the animal to retract completely into. When the word snail is used in this most general sense, it not just land snails but also thousands of species of sea snails. Occasionally a few other molluscs that are not actually gastropods, such as the Monoplacophora, snail-like animals that naturally lack a shell, or have only an internal shell, are mostly called slugs, and land snails that have only a very small shell are often called semi-slugs. Even a few species have lungs. Snails can be found in a wide range of environments, including ditches, deserts. Although land snails may be familiar to laymen, marine snails constitute the majority of snail species, and have much greater diversity. Numerous kinds of snail can also be found in fresh water, most snails have thousands of microscopic tooth-like structures located on a banded ribbon-like tongue called a radula. The radula works like a file, ripping food into small pieces, many snails are herbivorous, eating plants or rasping algae from surfaces with their radulae, though a few land species and many marine species are omnivores or predatory carnivores. Several species of the genus Achatina and related genera are known as giant African land snails, some grow to 15 in from snout to tail, and weigh 1 kg. The largest living species of sea snail is Syrinx aruanus, its shell can measure up to 90 cm in length, and the whole animal with the shell can weigh up to 18 kg. The snail Lymnaea makes decisions by using two types of neuron, one deciding whether the snail is hungry, and the other deciding whether there is food in the vicinity. Named Gee Geronimo, this snail was owned by Christopher Hudson of Hove, East Sussex, UK, gastropods that lack a conspicuous shell are commonly called slugs rather than snails. Some species of slug have a red shell, some have only a vestige that serves mainly as a calcium repository. Other than that there is little difference between slugs and snails. There are however important differences in habitats and behavior, slugs squeeze themselves into confined spaces such as under loose bark on trees or under stone slabs, logs or wooden boards lying on the ground. In such retreats they are in danger from either predators or desiccation. Slugs as a group are far from monophyletic, biologically speaking slug is a term of convenience with little taxonomic significance, the reduction or loss of the shell has evolved many times independently within several very different lineages of gastropods
Snail
–
Snail
Snail
–
Helix pomatia sealed in its shell with a
calcareous epiphragm.
Snail
–
Helix aspersa - garden snail
Snail
–
French cooked snails
13.
Mollusk
–
The molluscs compose the large phylum Mollusca of invertebrate animals. Around 85,000 extant species of molluscs are recognized, molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats and they are highly diverse, not just in size and in anatomical structure, but also in behaviour and in habitat. The phylum is divided into 9 or 10 taxonomic classes. The gastropods are by far the most numerous molluscs in terms of classified species, the three most universal features defining modern molluscs are a mantle with a significant cavity used for breathing and excretion, the presence of a radula, and the structure of the nervous system. Other than these things, molluscs express great morphological diversity, so many textbooks base their descriptions on an ancestral mollusc. This has a single, limpet-like shell on top, which is made of proteins and chitin reinforced with calcium carbonate, the underside of the animal consists of a single muscular foot. Although molluscs are coelomates, the coelom tends to be small, the main body cavity is a hemocoel through which blood circulates, their circulatory systems are mainly open. The generalized mollusc has two paired nerve cords, or three in bivalves, the brain, in species that have one, encircles the esophagus. Most molluscs have eyes, and all have sensors to detect chemicals, vibrations, the simplest type of molluscan reproductive system relies on external fertilization, but more complex variations occur. All produce eggs, from which may emerge trochophore larvae, more complex veliger larvae, good evidence exists for the appearance of gastropods, cephalopods and bivalves in the Cambrian period 541 to 485.4 million years ago. Molluscs have, for centuries, also been the source of important luxury goods, notably pearls, mother of pearl, Tyrian purple dye and their shells have also been used as money in some preindustrial societies. Mollusc species can also represent hazards or pests for human activities, the bite of the blue-ringed octopus is often fatal, and that of Octopus apollyon causes inflammation that can last for over a month. Stings from a few species of large tropical cone shells can also kill, schistosomiasis is transmitted to humans via water snail hosts, and affects about 200 million people. Snails and slugs can also be serious pests, and accidental or deliberate introduction of some snail species into new environments has seriously damaged some ecosystems. The words mollusc and mollusk are both derived from the French mollusque, which originated from the Latin molluscus, from mollis, molluscus was itself an adaptation of Aristotles τα μαλακά, the soft things, which he applied to cuttlefish. The scientific study of molluscs is accordingly called malacology, as it is now known these groups have no relation to molluscs, and very little to one another, the name Molluscoida has been abandoned. The most universal features of the structure of molluscs are a mantle with a significant cavity used for breathing and excretion
Mollusk
Mollusk
–
Cornu aspersum (formerly Helix aspersa) – a common land
snail
Mollusk
–
About 80% of all known mollusc species are
gastropods (
snails and
slugs), including this
cowry (a sea snail).
Mollusk
–
The use of
love darts by the land snail
Monachoides vicinus is a form of
sexual selection
14.
Mollusc
–
The molluscs compose the large phylum Mollusca of invertebrate animals. Around 85,000 extant species of molluscs are recognized, molluscs are the largest marine phylum, comprising about 23% of all the named marine organisms. Numerous molluscs also live in freshwater and terrestrial habitats and they are highly diverse, not just in size and in anatomical structure, but also in behaviour and in habitat. The phylum is divided into 9 or 10 taxonomic classes. The gastropods are by far the most numerous molluscs in terms of classified species, the three most universal features defining modern molluscs are a mantle with a significant cavity used for breathing and excretion, the presence of a radula, and the structure of the nervous system. Other than these things, molluscs express great morphological diversity, so many textbooks base their descriptions on an ancestral mollusc. This has a single, limpet-like shell on top, which is made of proteins and chitin reinforced with calcium carbonate, the underside of the animal consists of a single muscular foot. Although molluscs are coelomates, the coelom tends to be small, the main body cavity is a hemocoel through which blood circulates, their circulatory systems are mainly open. The generalized mollusc has two paired nerve cords, or three in bivalves, the brain, in species that have one, encircles the esophagus. Most molluscs have eyes, and all have sensors to detect chemicals, vibrations, the simplest type of molluscan reproductive system relies on external fertilization, but more complex variations occur. All produce eggs, from which may emerge trochophore larvae, more complex veliger larvae, good evidence exists for the appearance of gastropods, cephalopods and bivalves in the Cambrian period 541 to 485.4 million years ago. Molluscs have, for centuries, also been the source of important luxury goods, notably pearls, mother of pearl, Tyrian purple dye and their shells have also been used as money in some preindustrial societies. Mollusc species can also represent hazards or pests for human activities, the bite of the blue-ringed octopus is often fatal, and that of Octopus apollyon causes inflammation that can last for over a month. Stings from a few species of large tropical cone shells can also kill, schistosomiasis is transmitted to humans via water snail hosts, and affects about 200 million people. Snails and slugs can also be serious pests, and accidental or deliberate introduction of some snail species into new environments has seriously damaged some ecosystems. The words mollusc and mollusk are both derived from the French mollusque, which originated from the Latin molluscus, from mollis, molluscus was itself an adaptation of Aristotles τα μαλακά, the soft things, which he applied to cuttlefish. The scientific study of molluscs is accordingly called malacology, as it is now known these groups have no relation to molluscs, and very little to one another, the name Molluscoida has been abandoned. The most universal features of the structure of molluscs are a mantle with a significant cavity used for breathing and excretion
Mollusc
Mollusc
–
Cornu aspersum (formerly Helix aspersa) – a common land
snail
Mollusc
–
About 80% of all known mollusc species are
gastropods (
snails and
slugs), including this
cowry (a sea snail).
Mollusc
–
The use of
love darts by the land snail
Monachoides vicinus is a form of
sexual selection
15.
Exoskeleton
–
An exoskeleton is the external skeleton that supports and protects an animals body, in contrast to the internal skeleton of, for example, a human. In usage, some of the kinds of exoskeletons are known as shells. Examples of animals with exoskeletons include insects such as grasshoppers and cockroaches, the shells of certain sponges and the various groups of shelled molluscs, including those of snails, clams, tusk shells, chitons and nautilus, are also exoskeletons. Some animals, such as the tortoise, have both an endoskeleton and an exoskeleton, exoskeletons have a role in defense from pests and predators, support, and in providing an attachment framework for musculature. Exoskeletons contain chitin, the addition of calcium carbonate makes them harder and stronger, ingrowths of the arthropod exoskeleton known as apodemes serve as attachment sites for muscles. These structures are composed of chitin, and are six times as strong. Similar to tendons, apodemes can stretch to store energy for jumping. Many different species produce exoskeletons, which are composed of a range of materials, bone, cartilage, or dentine is used in the Ostracoderm fish and turtles. Chitin forms the exoskeleton in arthropods including insects, arachnids such as spiders, crustaceans such as crabs and lobsters, calcium carbonates constitute the shells of molluscs, brachiopods, and some tube-building polychaete worms. Silica forms the exoskeleton in the microscopic diatoms and radiolaria, one species of mollusc, the scaly-foot gastropod, even makes use of the iron sulfides greigite and pyrite. Some organisms, such as some foraminifera, agglutinate exoskeletons by sticking grains of sand, contrary to a common misconception, echinoderms do not possess an exoskeleton, as their test is always contained within a layer of living tissue. Exoskeletons have evolved many times,18 lineages evolved calcified exoskeletons alone. Further, other lineages have produced tough outer coatings analogous to an exoskeleton and this coating is constructed from bone in the armadillo, and hair in the pangolin. The armor of reptiles like turtles and Ankylosaurs is constructed of bone, crocodiles have bony scutes, since exoskeletons are rigid, they present some limits to growth. Organisms with open shells can grow by adding new material to the aperture of their shell, as is the case in snails, bivalves, a true exoskeleton, like that found in arthropods, must be shed when it is outgrown. A new exoskeleton is produced beneath the old one, as the old one is shed, the new skeleton is soft and pliable. The animal will pump itself up to expand the new shell to maximal size, when the shell has set, the empty space inside the new skeleton can be filled up as the animal eats. Failure to shed the exoskeleton once outgrown can result in the animal being suffocated within its own shell and this is the mechanism behind some insect pesticides, such as Azadirachtin
Exoskeleton
–
The discarded exoskeleton (
exuviae) of a
dragonfly nymph
Exoskeleton
–
Exoskeleton of
cicada attached to
Tridax procumbens
Exoskeleton
–
Borings in exoskeletons can provide evidence of animal behavior. In this case, boring
sponges attacked this
hard clam shell after the death of the clam, producing the trace fossil
Entobia.
16.
Slug
–
Slug, or land slug, is a common name for any apparently shell-less terrestrial gastropod mollusc. The word slug is often used as part of the common name of any gastropod mollusc that has no shell. Various taxonomic families of land slugs form part of quite different evolutionary lineages. Thus, the families of slugs are not closely related. The shell-less condition has arisen many times independently during the evolutionary past, of the six orders of Pulmonata, two – the Onchidiacea and Soleolifera – solely comprise slugs. A third family, the Sigmurethra, contains various clades of snails, the taxonomy of this group is in the process of being revised in light of DNA sequencing. It appears that pulmonates are paraphyletic and basal to the opisthobranchs, the family Ellobiidae are also polyphyletic. E. The upper pair is light sensing and has eyespots at the ends, mantle On top of the slug, behind the head, is the saddle-shaped mantle, and under this are the genital opening and anus. On one side of the mantle is an opening, which is easy to see when open. This opening is known as the pneumostome, tail The part of a slug behind the mantle is called the tail. Keel Some species of slugs, for example Tandonia budapestensis, have a prominent ridge running over their back along the middle of the tail and this ridge is called a keel. Foot The bottom side of a slug, which is flat, is called the foot, like almost all gastropods, a slug moves by rhythmic waves of muscular contraction on the underside of its foot. It simultaneously secretes a layer of mucus that it travels on, around the edge of the foot in some taxa is a structure called the foot fringe. Vestigial shell Most slugs retain a remnant of their shell, which is usually internalized and this organ generally serves as storage for calcium salts, often in conjunction with the digestive glands. An internal shell is present in the Limacidae and Parmacellidae, adult Philomycidae, Onchidiidae and Veronicellidae lack shells. Slugs bodies are made up mostly of water and, without a full-sized shell and they must generate protective mucus to survive. Many species are most active just after rain because of the moist ground, in drier conditions, they hide in damp places such as under tree bark, fallen logs, rocks and man-made structures, such as planters, to help retain body moisture. Like all other gastropods, they undergo torsion during development, Slugs produce two types of mucus, one is thin and watery, and the other thick and sticky
Slug
Slug
–
Various species of
British land slugs, including (from the top) the larger drawings:
Arion ater,
Kerry slug,
Limax maximus and
Limax flavus
Slug
–
An active
Ambigolimax slug in
Fremont, California
Slug
–
Deroceras juvenile with eggs
17.
Semi-slug
–
Semi-slugs, also spelled semislugs, are land gastropods whose shells are too small for them to retract into, but not quite vestigial. The shell of some semi-slugs may not be visible on casual inspection. This is a type of gastropod that is intermediate between a slug and a land snail, there exist a number of gastropod families that have semi-slugs species. There exist about 1000 species of semi-slugs in comparison to about only 500 species of slugs
Semi-slug
–
Drawing of two views of
Cryptella canariensis from the
Canary Islands
Semi-slug
–
An unidentified semi-slug from
Uganda
18.
Conchology
–
Conchology is the study of mollusc shells. Conchology is one aspect of malacology, the study of molluscs, however, malacology is the study of molluscs as whole organisms and it includes the study of land and freshwater mollusc shells as well as seashells and extends to the study of a gastropods operculum. Conchology is now seen as an archaic study, because relying on only one aspect of an organisms morphology can be misleading. However, a shell often gives at least some insight into molluscan taxonomy, even in current museum collections it is common for the dry material to greatly exceed the amount of material that is preserved whole in alcohol. Conchologists mainly deal with four orders, the gastropods, bivalves, Polyplacophora. Cephalopods only have internal shells, with the exception of the Nautiloidea. Some groups, such as the sea slug nudibranchs, have lost their shells altogether, the terms shell collector and conchologist can be regarded as two distinct categories. Not all shell collectors are conchologists, some are concerned with the aesthetic value of shells instead of their scientific study. It is also true that not all conchologists are shell collectors, there is some debate in the conchological community, with some people regarding all shell collectors as conchologists. Molluscs have probably been used by primates as a food long before humans evolved. Shell collecting, the precursor of conchology, probably goes back as far as there have been living near beaches. Stone Age seashell necklaces have been found, sometimes in areas far from the ocean, Shell jewellery is found at almost all archaeological sites, including at ancient Aztec ruins, digs in ancient China, and the Indus Valley. During the Renaissance people began taking interest in objects of beauty to put in cabinets of curiosities. Because of their attractiveness, variety, durability and ubiquity, shells became a part of these collections. Towards the end of the 17th century, people looking at shells with scientific interest. Martin Lister in 1685–1692 published Historia Conchyliorum, which was the first comprehensive conchological text, george Rumpf, or Rumphius, published the first mollusc taxonomy. He suggested single shelled ones, snails or whelks, and two-shelled ones, many of Rumpfs terms were adopted by Carl Linnaeus. Rumpf continued to do important scientific work after he went blind, the study of zoology, including conchology, was revolutionized by Swedish naturalist Carl Linnaeus and his system of binomial nomenclature
Conchology
–
Calliostoma tigris
Conchology
–
Shell of
Lobatus gigas, the queen conch
Conchology
–
A vendor in
Tanzania with a variety of large
seashells for sale
19.
Malacology
–
Malacology is the branch of invertebrate zoology that deals with the study of the Mollusca, the second-largest phylum of animals in terms of described species after the arthropods. Mollusks include snails and slugs, clams, octopus and squid, one division of malacology, conchology, is devoted to the study of mollusk shells. Malacology derives from Greek μαλακός, malakos, soft, and -λογία, fields within malacological research include taxonomy, ecology and evolution. Applied malacology studies medical, veterinary, and agricultural applications, for example mollusks as vectors of disease, archaeology employs malacology to understand the evolution of the climate, the biota of the area, and the usage of the site. In 1681, Filippo Bonanni wrote the first book published that was solely about seashells. The book was entitled, Ricreatione dell occhio e dela mente nell oservation delle Chiociolle, proposta a curiosi delle opere della natura, in 1868, the German Malacological Society was founded. Zoological methods are used in malacological research, Malacological field methods and laboratory methods were summarized by Sturm et al. Those who study malacology are known as malacologists and those who study primarily or exclusively the shells of mollusks are known as conchologists. The Conchologist -> The Journal of Malacology The Festivus - a peer-reviewed journal which started as a newsletter in 1970. The Nautilus - since 1886 published by Bailey-Matthews Shell Museum, First two volumes were published under name The Conchologists’ Exchange. Impact factor,0.500 The Veliger - impact factor,0, proceedings of the First European Malacological Congress. Text in English with black-and-white photographic reproductions, also maps and diagrams, published by the Conchological Society of Great Britain and Ireland and the Malacological Society of London in 1965 with no ISBN. The long dawn of Malacology, a history of malacology from prehistory to the year 1800. Archives of Natural History 22, 301-319, media related to Malacology at Wikimedia Commons Periodicals about molluscs at WorldCat
Malacology
–
Teuthology, a branch of malacology, deals with the study of
cephalopods, such as the
giant squid pictured.
Malacology
–
Malacological Museum in
Makarska,
Croatia (entrance)
20.
Mantle (mollusc)
–
The mantle is a significant part of the anatomy of molluscs, it is the dorsal body wall which covers the visceral mass and usually protrudes in the form of flaps well beyond the visceral mass itself. In many species of molluscs the epidermis of the mantle secretes calcium carbonate and conchiolin, in sea slugs there is a progressive loss of the shell and the mantle becomes the dorsal surface of the animal. The words mantle and pallium both originally meant cloak or cape, see mantle, the mantle cavity is a central feature of molluscan biology. This cavity is formed by the skirt, a double fold of mantle which encloses a water space. This space contains the gills, anus, osphradium, nephridiopores. The mantle cavity functions as a chamber in most molluscs. In bivalves it is part of the feeding structure. In some molluscs the mantle cavity is a chamber, and in cephalopods and some bivalves such as scallops. In cephalopods the contraction of the mantle is used to water through a tubular siphon, the hyponome. In gastropods it is used as a kind of foot for locomotion over the surface, in Patella the foot includes the entire ventral surface of the animal. The foot of the Bivalvia is a fleshy process adapted by its form to digging rather than to locomotion, in shelled molluscs, the mantle is the organ that forms the shell, and adds to the shell to increase its size and strength as the animal grows. Shell material is secreted by the cells of the mantle tissue. The mantle of many gastropods is usually fully or partially hidden inside the gastropod shell, in species where the shell is small compared to the size of the body, more of the mantle shows. Shell-less slugs have the mantle fully visible, the dorsal surface of the mantle is called the notum, while the ventral surface of the mantle is called the hyponotum. In the family Philomycidae, the covers the whole back side of the body. Mollusc shell, which is formed by the mantle Siphon, which is a part of the mantle in some groups of molluscs
Mantle (mollusc)
–
European squid (Loligo vulgaris). The mantle is all that is visible behind the head: the outer body wall and the fins are all part of the mantle.
Mantle (mollusc)
–
The brightly coloured mantle of a
giant clam protects it from bright sunlight.
Mantle (mollusc)
–
The marine
gastropod Cypraea chinensis, the Chinese cowry, showing its partially extended mantle.
Mantle (mollusc)
–
Cypraea chinensis with its mantle fully extended.
21.
Nacre
–
Nacre, also known as mother of pearl, is an organic-inorganic composite material produced by some molluscs as an inner shell layer, it also makes up the outer coating of pearls. It is strong, resilient, and iridescent, nacre is found in some of the most ancient lineages of bivalves, gastropods, and cephalopods. The outer layer of pearls and the layer of pearl oyster and freshwater pearl mussel shells are made of nacre. Other mollusc families that have an inner shell layer include marine gastropods such as the Haliotidae, the Trochidae. Nacre is composed of hexagonal platelets of aragonite 10–20 µm wide and 0.5 µm thick arranged in a continuous parallel lamina and these layers are separated by sheets of organic matrix composed of elastic biopolymers. This mixture of brittle platelets and the layers of elastic biopolymers makes the material strong and resilient. Strength and resilience are also likely to be due to adhesion by the arrangement of the platelets. This structure, at multiple length sizes, greatly increases its toughness, nacre appears iridescent because the thickness of the aragonite platelets is close to the wavelength of visible light. These structures interfere constructively and destructively with different wavelengths of light at different viewing angles, the crystallographic c-axis points approximately perpendicular to the shell wall, but the direction of the other axes varies between groups. Adjacent tablets have shown to have dramatically different c-axis orientation. In bivalves and cephalopods, the points in the direction of shell growth. The interlocking of bricks of nacre has large impact on both the mechanism as well as its toughness. In addition, the mineral–organic interface results in enhanced resilience and strength of the organic interlayers, nacre formation is not fully understood. The initial onset assembly, as observed in Pinna nobilis, is driven by the aggregation of nanoparticles within a matrix that arrange in fibre-like polycrystalline configurations. The particle number increases successively and, when critical packing is reached, nacre growth is mediated by organics, controlling the onset, duration and form of crystal growth. Individual aragonite bricks are believed to grow to the full height of the nacreous layer. This produces the hexagonal close-packing characteristic of nacre, bricks may nucleate on randomly dispersed elements within the organic layer, well-defined arrangements of proteins, or may grow epitaxially from mineral bridges extending from the underlying tablet. Nacre differs from fibrous aragonite – a brittle mineral of the same form – in that the growth in the c-axis is slow in nacre, nacre is secreted by the epithelial cells of the mantle tissue of various molluscs
Nacre
–
The iridescent nacre inside a
Nautilus shell.
Nacre
–
Electron microscopy image of a fractured surface of nacre
Nacre
–
Fossil
nautiloid shell with original iridescent nacre in fossiliferous asphaltic limestone,
Oklahoma. Dated to the late Middle Pennsylvanian, which makes it - by far - the oldest deposit in the world with aragonitic nacreous shelly fossils.
22.
Calcium carbonate
–
Calcium carbonate is a chemical compound with the formula CaCO3. It is a substance found in rocks as the minerals calcite and aragonite and is the main component of pearls and the shells of marine organisms, snails. Calcium carbonate is the ingredient in agricultural lime and is created when calcium ions in hard water react with carbonate ions to create limescale. It is medicinally used as a supplement or as an antacid. Calcium carbonate shares the properties of other carbonates. CaCO3 + CO2 + H2O → Ca2 This reaction is important in the erosion of rock, forming caverns. An unusual form of calcium carbonate is the hexahydrate, ikaite, ikaite is stable only below 6 °C. The vast majority of calcium used in industry is extracted by mining or quarrying. Pure calcium carbonate, can be produced from a quarried source. Alternatively, calcium carbonate is prepared from calcium oxide, other forms can be prepared, the denser, orthorhombic λ-CaCO3 and μ-CaCO3, occurring as the mineral vaterite. The aragonite form can be prepared by precipitation at temperatures above 85 °C, calcite contains calcium atoms coordinated by 6 oxygen atoms, in aragonite they are coordinated by 9 oxygen atoms. The vaterite structure is not fully understood, magnesium carbonate MgCO3 has the calcite structure, whereas strontium and barium carbonate adopt the aragonite structure, reflecting their larger ionic radii. Calcite, aragonite and vaterite are pure calcium carbonate minerals, industrially important source rocks which are predominantly calcium carbonate include limestone, chalk, marble and travertine. Eggshells, snail shells and most seashells are predominantly calcium carbonate, oyster shells have enjoyed recent recognition as a source of dietary calcium, but are also a practical industrial source. While not practical as a source, dark green vegetables such as broccoli. Beyond Earth, strong evidence suggests the presence of Calcium carbonate on Mars, signs of Calcium Carbonate have been detected at more than one location. This provides some evidence for the past presence of liquid water, Carbonate is found frequently in geologic settings and constitute an enormous carbon reservoir. Calcium carbonate occurs as aragonite, calcite and dolomite, the carbonate minerals form the rock types, limestone, chalk, marble, travertine, tufa, and others
Calcium carbonate
–
Calcium carbonate
Calcium carbonate
–
500-milligram calcium supplements made from calcium carbonate
Calcium carbonate
–
Travertine calcium carbonate deposits from a
hot spring
23.
Conchiolin
–
Conchiolins are complex proteins which are secreted by a molluscs outer epithelium. These proteins are part of a matrix of organic macromolecules, mainly proteins and polysaccharides and this organic matrix also holds and binds to the crystals of aragonite which give such shells their stiffness. Some land snails have thin, transparent, tan-colored shells, even as adults. Mollusc shell Periostracum Corneous Chitin Tectin Sporopollenin Structure of the cases of the prisms in Mytilus edulis
Conchiolin
–
The shell of
Stenotrema florida, a land snail. The
periostracum is an organic layer of protein which, in this species, is developed into minute hairs, giving the snail a velvety look and feel
24.
Zonitoides nitidus
–
Zonitoides nitidus is a species of small, air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Gastrodontidae. Zonitoides nitidus is the species of the genus Zonitoides. The distribution of Zonitoides nitidus includes the Holarctic zone, in some regions in Britain the species has declined due to drainage. Ireland Hebrides Orkney Shetland rare in northern Greece Canada The non-indigenous distribution of species includes. The shell is with radial growth lines, the width of the shell is 6–7 mm. The height of the shell is 3. 5-4.0 mm, the animal is black with a characteristic orange dash, the. Juveniles are whitish grey with light brown translucent shells, Zonitoides nitidus occurs in wet meadows and river woods, usually near water bodies, swamps and swampy forests, in the zone of emergent vegetation. Man-made habitats such as pools in old quarries are sometimes colonized after a few years, in Switzerland it is found up to 2100m of altitude. These snails feed on disintegrating leaves, mushrooms, roots and fruit and they do not eat dry leaves. In Germany up to three clutches of 2-9 eggs per individual are laid in all seasons, with days or weeks spacing between egg-laying. Egg diameter is 1. 0-1.6 mm. Eggs are laid loose into the soil, juveniles have 1.5 whorls after hatching. They start feeding on disintegrating plant remains in the soil, after 3 months the shell diameter reaches up to 3 mm under favourable conditions, after 10 months 6 mm, and full size after slightly more than one year. Maximum age is 18 months under laboratory conditions, parasites of Zonitoides nitidus include, Elaphostrongylus spp. Parelaphostrongylus tenuis This article incorporates public domain text from the reference
Zonitoides nitidus
–
Zonitoides nitidus
Zonitoides nitidus
–
Photo of the shell.
25.
Abalone
–
Abalone is a common name for any of a group of small to very large sea snails, marine gastropod molluscs in the family Haliotidae. Other common names are ear shells, sea ears, and muttonfish or muttonshells in Australia, ormer in Great Britain, perlemoen in South Africa and their taxonomy puts them in the family Haliotidae which contains only one genus, Haliotis, which once contained six subgenera. These subgenera have become alternate representations of Haliotis, the number of species recognized worldwide ranges between 30 and 130 with over 230 species-level taxa described. The most comprehensive treatment of the family considers 56 species valid, the shells of abalones have a low, open spiral structure, and are characterized by several open respiratory pores in a row near the shells outer edge. The flesh of abalones is widely considered to be a desirable food, Abalone vary in size from 20 millimetres to 200 millimetres while Haliotis rufescens is the largest of the genus at 12 inches. The shell of abalones is convex, rounded to oval in shape, the shell of the majority of species has a small, flat spire and two to three whorls. The last whorl, known as the whorl, is auriform, meaning that the shell resembles an ear. Haliotis asinina has a different shape, as it is more elongated and distended. The shell of Haliotis cracherodii cracherodii is also unusual as it has a form, is imperforate, shows an exserted spire. A mantle cleft in the shell impresses a groove in the shell and these holes are respiratory apertures for venting water from the gills and for releasing sperm and eggs into the water column. They make up what is known as the selenizone which forms as the shell grows and this series of 8 to 38 holes is near the anterior margin. Only a small number are generally open, the older holes are gradually sealed up as the shell grows and new holes form. Each species has a number of open holes, between four and ten, in the selenizone. The aperture of the shell is wide and nacreous. The exterior of the shell is striated and dull, the color of the shell is very variable from species to species which may reflect the animals diet. The iridescent nacre that lines the inside of the shell varies in color from white, to pink, red and green-red to deep blue. The animal has fimbriated head-lobes and side-lobes which are fimbriated and cirrated, the radula has small median teeth, and the lateral teeth are single and beam-like. There are about 70 uncini, with denticulated hooks, the first four very large, the rounded foot is very large in comparison to most molluscs
Abalone
Abalone
–
The
iridescent surface inside a
red abalone shell from
Northern California (the adjacent coin is 18mm in diameter)
Abalone
–
Abalone with a live sponge on its shell in
Póvoa de Varzim,
Portugal
Abalone
–
An abalone farm
26.
Turritella
–
Turritella is a genus of medium-sized sea snails with an operculum, marine gastropod mollusks in the family Turritellidae. They have tightly coiled shells, whose shape is basically that of an elongated cone. The name Turritella comes from the Latin word turritus meaning turreted or towered, valid species within the genus Turritella are listed below. Fossil species are marked with a dagger †. B, sowerby I,1825 Turritella brevialis Lamarck,1822, synonym of Mesalia brevialis Turritella canaliculata Adams & Reeve,1850, synonym of Turritella cingulifera G. B. Sowerby III,1870, synonym of Turritella declivis Adams & Reeve in Reeve,1849 Turritella flammulata Kiener, 1843-44, sowerby III,1914, synonym of Neohaustator fortilirata Turritella gracillima Gould,1860, synonym of Turritella cingulifera G. B. Both varieties of stone are commonly sold as polished cabochons. One variety of Turritella agate, that from the Green River Formation in Wyoming, is a rock which does indeed contain numerous high-spired snail shells. However, contrary to the name, these snails are not in the marine genus Turritella, instead they are freshwater snails in the species Elimia tenera. The rock in which snail shells are so abundant varies from a soft sandstone to a dense chalcedony. This dense silicified rock is popular with gem and mineral hobbyists, the Erminger Turritellenplatte near Ulm, Germany is a rocky outcrop situated in the northern part of the North Alpine Foreland Basin. It is famous for its superabundance of Turritella turris shells within its sediments, caenogastropoda in Man and Mollusc 1. Turritella canaliculata, New York Public Library no-charge digital image available, image dated 1850
Turritella
Turritella
–
Numerous shells of a Turritella species washed up on the beach at
Playa Grande, Costa Rica
Turritella
–
Fossil specimens of Turritella incrassata
27.
Planorbidae
–
Planorbidae, common name the ramshorn snails or rams horn snails, is a family of air-breathing freshwater snails, aquatic pulmonate gastropod mollusks. The foot and head of planorbids are rather small, while their tentacles are relatively long. For information on what are known as ramshorn snails in the trade, some of which are planorbids. For several taxa, no consensus exists as to whether the taxa should even be assigned to the family Planorbidae and this is certainly the case with the freshwater limpets Ferrissia, and Ancylus. Both of these genera have sometimes been assigned to the family Lymnaeidae, alternatively sometimes each one of them is raised to the level of a family. However, according to the taxonomy of the Gastropoda, these genera are placed in the tribe Ancylini within the family Planorbidae. F. Müller 1774 Tribus Segmentinini Segmentina Fleming,1818 Hippeutis Charpentier,1837 Polypylis Pilsbry,1906 C-Clade sensu Albrecht et al, Biomphalaria Preston,1910 Menetus H. & A. The following list of genera is organized according to the 2005 taxonomy and it was recognised by Curry as a euthecosomatous pteropod. The generic name Taphius H. Adams & A. Adams,1855 is a synonym for Biomphalaria. The shells of most species in this family are disk-like or button-like, being coiled in one plane, although several groups have shells that are more higher-spired, and some are limpet-like. Indeed, formerly planorbids were thought to have shells. Although it is now understood that species are sinistral in shell coiling. Most species of coiled planorbids have a thin and moderately smooth shell, although more distinct sculpture such as a keel occurs in. In the flat, keeled species, the whorls tend to overlap, the aperture has a sharp outer lip. A peristome can be present, but often the lip is not thickened nor reflected and those planorbid species which have a high-spired shell may have a narrow umbilicus, but frequently this is covered by callus. In height most species vary between 6 mm and 6 cm, however, disk-like shells are less than about 2 cm in maximum dimension. Like all pulmonate snails, ramshorn shells do not have an operculum to close the shell aperture. Flat-coiled planorbid gastropod shells are hard to understand in terms of their coiling, in addition these are in fact sinistral shells, despite the fact that the snail carries its shell as if it were a normal dextral shell
Planorbidae
–
Planorbidae
Planorbidae
–
View of the sunken
spire of the shell of
Anisus septemgyratus
Planorbidae
–
Planorbarius corneus. View of the sunken
spire (held facing downwards in life)
Planorbidae
–
Planorbarius corneus. View of the
umbilicus (held uppermost in life)
28.
Turban shell
–
Turbinidae, the turban snails, are a family of small to large marine gastropod molluscs in the superfamily Trochoidea. Turbinidae have a strong, thick calcareous operculum readily distinguishing them from the somewhat similar Trochidae or top snails and this strong operculum serves as a passive defensive structure against predators that try to enter by way of the aperture or that would break the shell at the outer lip. The common name turban snail presumably refers to the similarity in appearance to a turban. However, the scientific name Turbinidae is based on the genus name Turbo, which is Latin for spinning top, the word turbine has a similar derivation. Previously they were classified in the subclass Prosobranchia, in the order Archaeogastropoda in the superfamily Trochacea, trochaecea is now a synonym for the superfamily Trochoidea. However, this is an ancient group of gastropods, probably originating in the Permian period 298 to 250 million years ago. They have typical primitive characters like the interior of the shell. Turbinidae belongs to superfamily Turbinoidea according to the taxonomy of the Gastropoda by Bouchet & Rocroi, angariidae was elevated to family level, Colloniinae was elevated to family Colloniidae within Phasianelloidea, Margaritinae was moved to Turbinidae from Trochidae. This family consists of five following subfamilies according to Williams et al, the family has a large distribution, from the tropics to the polar regions, but most of the species live in tropical and subtropical shallow waters. Sowerby I,1838, synonym of Norrisia Bayle,1880 † Tylastralium Sacco,1896, synonym of Bolma Risso,1826 Valvatella Gray,1857, synonym of Margarites Gray,1847 Marshall, B. A.1988. Skeneidae, Vitrinellidae and Orbitestellidae associated with biogenic substrata from bathyal depths off New Zealand, journal of Natural History 22, 949-1004. A classification of the living Mollusca, molecular systematics of Vetigastropoda, Trochidae, Turbinidae and Trochoidea redefined. Seashells of New South Wales, Turbinidae Seashells of New South Wales, Skeneinae
Turban shell
–
Turbinidae
Turban shell
–
The shell of
Guildfordia yoka, a deep water turbinid
Turban shell
–
Lithopoma tectum
29.
Cone shell
–
Conidae, with the current common name of cone snails, is a taxonomic family of predatory sea snails, marine gastropod molluscs in the superfamily Conoidea. The 2014 classification of the superfamily Conoidea, groups only cone snails in the family Conidae, some previous classifications grouped the cone snails in a subfamily, the Coninae. Conidae currently contains over 800 recognized species, working in 18th century Europe, Linnaeus knew of only 30 species which are still considered valid. The snails within this family are sophisticated predatory animals and they hunt and immobilize prey using a modified radular tooth along with a venom gland containing neurotoxins, the tooth is launched out of the snails mouth in a harpoon-like action. Because all cone snails are venomous and capable of stinging humans, in the Journal of Molluscan Studies, in 2014, Puillandre, Duda, Meyer, Olivera & Bouchet presented a new classification for the old genus Conus. Using 329 species, the authors carried out molecular phylogenetic analyses, the results suggested that the authors should place all living cone snails in a single family, Conidae, containing four genera, Conus, Conasprella, Profundiconus and Californiconus. The authors grouped 85% of all known cone snail species under Conus, They recognized 57 subgenera within Conus, prior to 1993, the family Conidae contained only Conus species. In 1993, significant taxonomic changes were proposed by Taylor, et al. the family Conidae was redefined as several subfamilies, the subfamilies included many subfamilies which had previously been classified in the family Turridae, and the Conus species were moved to the subfamily Coninae. This left the family Conidae once again containing only those species which were placed in that family. According to Taylor, et al. and the taxonomy of the Gastropoda by Bouchet & Rocroi,2005, Tucker and Tenorio’s proposed classification system for the cone shells and their allies is shown in Tucker & Tenorio cone snail taxonomy 2009. Conorbiinae was raised to the rank of family Conorbidae, consisting of three genera, Artemidiconus da Motta,1991, Benthofascis Iredale,1936, and Conorbis Swainson,1840. Mangeliinae and Oenopotinae were combined and raised to the rank of family Mangeliidae, raphitominae was raised to the rank of family Raphitomidae. The classification by Bouchet et al. was based on mitochondrial DNA and nuclear DNA testing, and built on the work by J. K. Tucker & M. J. Tenorio. Molecular phylogeny, particularly with the advent of nuclear DNA testing in addition to the testing, is continuing on the Conidae. However, as a result of molecular studies in 2011, many of those genera were moved back to the Turridae. The following list of genera that used to be included in Conidae is retained as a historical reference, human victims suffer little pain, because the venom contains an analgesic component. Some species reportedly can kill a human in under five minutes, Cone snails can sting through a wetsuit with their harpoon-like radular tooth, which resembles a transparent needle. Normally, cone snails use their venom to immobilize prey before engulfing it, the venom consists of a mixture of peptides, called conopeptides
Cone shell
–
Conidae
30.
Murex
–
Murex is a genus of medium to large sized predatory tropical sea snails. These are carnivorous marine gastropod molluscs in the family Muricidae, commonly called murexes or rock snails, the word murex was used by Aristotle in reference to these kinds of snails, thus making it one of the oldest classical seashell names still in use by the scientific community. This genus is known in the records from the Cretaceous to the Quaternary. Fossils of species within this genus have been all over the world. There are about 25 extinct species, Murex is solely an Indo-Pacific genus, as demonstrated by Ponder & Vokes. The species from the western Atlantic that were considered to belong in the genus Murex are now placed in the genus Haustellum. Most Murex species live in the intertidal or shallow subtidal zone, among rocks and this genus includes many showy members, their elongate shells highly sculptured with spines or fronds. The inner surfaces of their shells are often brightly colored. This dye is a rare animal-produced organobromine compound, which the snails make using a specific enzyme that operates on dissolved bromide in sea water. This dye was used in royal robes, other kinds of ceremonial or ritual garments. A consensus has yet to be reached regarding the Biblical source of the blue dye, the genus Murex, as originally defined by Linnaeus, encompassed many taxa that are now placed elsewhere in the superfamily Muricoidea. Malacologists of the 19th century including Kiener, Reeve, Küster & Kobelt and this is the main reason why Murex has so many synonyms. The World Register of Marine Species, lists the species and subspecies with accepted names within the genus Murex. Species mentioned as species in current use in the Indo-Pacific Molluscan Database Murex singaporensis A. B. Garrigues, fossil and Recent Muricidae of the World, Part Muricinae. 648 pp.182 colour plates, Hackenheim, a revision of the Indo-West Pacific fossil and Recent species of Murex s. s. and Haustellum. Records of the Australian Museum, Supplement 8
Murex
Murex
–
Murex altispira
Murex
–
Fossil shell of Murex spinicosta from
Pliocene of Italy
31.
Conch
–
Conch is a common name that is applied to a number of different medium to large-sized sea snails or their shells. The term generally applies to large snails whose shell has a high spire, in North America, a conch is often identified as a queen conch, found off the coast of Florida. Queen conches are valued for fish bait, and are known as seafood. The group of conchs that are referred to as true conchs are marine gastropod molluscs in the family Strombidae, specifically in the genus Strombus. For example, see Lobatus gigas, the conch, and Laevistrombus canarium. Many other species are often called conch, but are not at all closely related to the family Strombidae, including Melongena species. Species commonly referred to as conchs also include the sacred chank or more correctly shankha shell, the English word conch is attested in Middle English, coming from Latin concha, which in turn comes from Greek konchē ultimately from PIE root *konkho-, cognate with Sanskrit śaṅkha. The meat of conchs is eaten raw in salads, or cooked, as in burgers, chowders, fritters, all parts of the conch meat are edible. In The Bahamas, conch is served in fritter form, or as a raw. In the West Indies, local people eat conch in soups, stews, restaurants all over the islands serve this particular meat. In the Dominican Republic, Grenada, and Haiti, conch is commonly eaten in curries or in a spicy soup and it is locally referred to as lambi. In The Turks and Caicos Islands, the Annual Conch Festival is held in November each year, local restaurateurs compete for the best and most original conch dishes, that are then judged by international chefs. Free sampling of the dishes follows the judging, along with those festivities, other competitions, events, and music performances occur well into the evening. In Puerto Rico, conch is served as a ceviche, often called ensalada de carrucho, consisting of raw conch marinated in lime juice, olive oil, vinegar, garlic, green peppers and it is also used to fill empanadas. In East Asian cuisines, this seafood is often cut into thin slices, Conch shells can be used as wind instruments. They are prepared by cutting a hole in the spire of the shell near the apex, sometimes a mouthpiece is used, but some shell trumpets are blown without one. Many different kinds of mollusks can produce pearls, pearls from the queen conch, L. gigas, are rare and have been collectors items since Victorian times. In some gemological texts, non-nacreous gastropod pearls used to be referred to as calcareous concretions because they were porcellaneous, rather than nacreous, although non-nacreous, the surface of fine conch pearls has a unique and attractive appearance of its own
Conch
–
Apertural view of an adult shell of the queen conch
Lobatus gigas, from
Trinidad & Tobago
Conch
–
A shell of the Florida crown conch
Melongena corona inhabited by a
hermit crab
Conch
–
A group of large eastern conchs or
whelks of the species
Busycotypus canaliculatus for sale at a California seafood market
Conch
–
A drawing of the shell of
Strombus alatus, the Florida fighting conch
32.
Cowry
–
Cowry or cowrie, plural cowries, is the common name for a group of small to large sea snails, marine gastropod molluscs in the family Cypraeidae, the cowries. The word cowry is also used to refer only to the shells of these snails. Many people throughout history have found the very rounded, shiny, porcelain-like shells of cowries pleasing to look at, indeed, the term porcelain derives from the old Italian term for the cowrie shell due to their similar translucent appearance. The cowry was the shell most widely used worldwide as shell money, cowry shell money was important at one time or another in the trade networks of Africa, South Asia, and East Asia. Some species in the family Ovulidae are also referred to as cowries. In the British Isles the local Trivia species are sometimes called cowries, the Ovulidae and the Triviidae are somewhat closely related to Cypraeidae. The shells of cowries are usually smooth and shiny and more or less egg-shaped, with a flat surface which shows a long, narrow, slit-like opening. The narrower end of the cowry shell is the anterior end. The spire of the shell is not visible in the shell of most species, but is visible in juveniles. Nearly all cowries have a porcelain-like shine, with exceptions such as Hawaiis granulated cowry. Lengths range from 5 mm for some species up to 19 cm for the Atlantic deer cowry, the word cowrie comes from Hindi कौड़ी and ultimately from Sanskrit कपर्द. Cowry shells, especially Monetaria moneta, were used for centuries as currency in Africa, after the 1500s, however, it became even more common. Western nations, chiefly through the trade, introduced huge amounts of Maldivian cowries in Africa. The Ghanaian unit of currency known as the Ghanaian cedi was named after cowry shells, starting over three thousand years ago, cowry shells, or copies of the shells, were used as Chinese currency. They were also used as means of exchange in India, the Classical Chinese character for money originated as a stylized drawing of a Maldivian cowrie shell. Words and characters concerning money, property or wealth usually have this as a radical, before the Spring and Autumn period the cowrie was used as a type of trade token awarding access to a feudal lords resources to a worthy vassal. There is some debate about how the Ojibway traded for or found these shells, so far inland and so far north, oral stories and birch bark scrolls seem to indicate that the shells were found in the ground, or washed up on the shores of lakes or rivers. Petroforms in the Whiteshell Provincial Park may be as old as 8,000 years, cowry shells are also worn as jewelry or otherwise used as ornaments or charms
Cowry
–
A print from 1845 shows cowry shells being used as money by an Arab trader.
Cowry
–
Shells of various species of cowries; all but one have their anterior ends pointing towards the top of the page in this image
Cowry
–
A live map cowry
Cypraea mappa in
East Timor
Cowry
–
Cowrie shells used as dice, showing a roll of 3
33.
Intertidal
–
The intertidal zone, also known as the foreshore and seashore and sometimes referred to as the littoral zone, is the area that is above water at low tide and under water at high tide. This area can include different types of habitats, with many types of animals, such as starfish, sea urchins. The well-known area also includes rocky cliffs, sandy beaches. The area can be a strip, as in Pacific islands that have only a narrow tidal range. Organisms in the zone are adapted to an environment of harsh extremes. The intertidal zone is home to many several species from different taxa including Porifera, Annelids, Coelenterates, Mollusks, crustaceans, Arthropods. Water is available regularly with the tides but varies from fresh with rain to highly saline, wave splash can dislodge residents from the littoral zone. With the intertidal zones high exposure to the sun, the range can be anything from very hot with full sun to near freezing in colder climates. Some microclimates in the zone are ameliorated by local features. Adaptation in the littoral zone allows the use of nutrients supplied in high volume on a basis from the sea. Edges of habitats, in this land and sea, are themselves often significant ecologies. Along most shores, the zone can be clearly separated into the following subzones, high tide zone, middle tide zone. The intertidal zone is one of a number of biomes or habitats, including estuaries, neritic, surface. Marine biologists divide the region into three zones, based on the overall average exposure of the zone. The low intertidal zone, which borders on the shallow subtidal zone, is exposed to air at the lowest of low tides and is primarily marine in character. The mid intertidal zone is exposed and submerged by average tides. The high intertidal zone is covered by the highest of the high tides. The high intertidal zone borders on the splash zone, on shores exposed to heavy wave action, the intertidal zone will be influenced by waves, as the spray from breaking waves will extend the intertidal zone
Intertidal
–
The rocky shoreline of
Newport,
Rhode Island, USA showing a clear line where high tide occurs.
Intertidal
–
Bancao Beach at Low Tide showing Intertidal Zone from about 200 m from the beach
Intertidal
–
Tide pools at Pillar Point showing zonation on the edge of the rock ledge
Intertidal
–
A rock, seen at low tide, exhibiting typical intertidal zonation, Kalaloch,
Washington, western
USA.
34.
Olive
–
Olea europeana sylvestris is a subspecies that corresponds to a smaller tree bearing noticeably smaller fruits. The olives fruit, also called the olive, is of agricultural importance in the Mediterranean region as the source of olive oil. The tree and its fruit give their name to the plant family, which includes species such as lilacs, jasmine, Forsythia. The word derives from Latin ŏlīva a borrowing from the Greek ἐλαία, the oldest attested forms of the Greek words are the Mycenaean
Olive
–
Olive
Olive
–
19th-century illustrations
Olive
–
Storing olives on
Dere Street;
Tacuinum Sanitatis, 14th century,
Olive
–
An olive vat room used for curing.
35.
Vermetidae
–
The Vermetidae, the worm snails or worm shells, are a taxonomic family of small to medium-sized sea snails, marine gastropod molluscs in the clade Littorinimorpha. The shells of species in the family Vermetidae are extremely irregular and these snails usually grow cemented onto a hard surface, or cemented together in colonies. In the adult, the part of the shell is usually free. Some species have an operculum and some do not, damaged sections of the shell can be sealed off by calcareous septa when necessary. Some vermetids are solitary, whereas others live in colonies, partially cemented together, the shells of species within this family vary greatly and can sometimes be extremely challenging to identify. The empty calcareous tubes of certain marine annelid worms, for example the Serpulidae, can sometimes be casually misidentified as empty vermetid shells. The difference is that vermetid shells are shiny inside and have three layers, whereas the annelid worm tubes are dull inside and have only two shell layers. The Vermetidae were recognized as the family in the superfamily Vermetoidea in the taxonomy of Bouchet & Rocroi within the clade Littorinimorpha. Studies, based on sperm ultrastructure, and on molecular data place it within the clade Littorinimorpha. However, there are still a number of authors place it within the superfamily Cerithioidea. The genera Campanile and Thylacodes form a clade that is sister to the Cerithioidea, bivonia Gray,1842 Eualetes Keen,1971 Novastoa Finlay,1926 Petaloconchus I. W. B. New Zealand Mollusca, William Collins Publishers Ltd, Auckland, New Zealand 1979 ISBN 0-00-216906-1 R. Tucker Abbott,1986, seashells of North America, St. Martins Press, New York Vaught, K. C. A classification of the living Mollusca
Vermetidae
–
Vermetidae
Vermetidae
–
Fossil Vermetus sp.; Nicosia Formation; Pliocene; Cyprus.
36.
Amphidromus perversus
–
Amphidromus perversus is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Camaenidae. Amphidromus perversus is the species of the genus Amphidromus, by the subsequent designation of Eduard von Martens. Absent from the Mentawi Chain and Panaitan Island and its occurrence on Sumbawa needs confirmation. Probably it has introduced into Singapore. Subspecies recognized here are from Great Natuna, Bawean, Kangean Islands, in Amphidromus perversus and most other thick-shelled Amphidromus species, the lip is internally thickened, forms a roll in its expansion, and has a very heavy parietal callus. The shell is solid, polished, amphidromine, moderately large high, lip and callus white, ground color white, orange, yellow, or yellowish-green. Many specimens with interrupted or continuous radial brownish streaks covering part or all of the whorls on the lower spire, Amphidromus perversus undoubtedly offers the greatest array of discretely variable color combinations of any species of Amphidromus. Amphidromus perversus perversus f. aureus Martyn,1784 — It still have not been reported from a precise locality and it was based on three shells collected by Sir Joseph Banks, supposedly on Pulau Panaitan. The only Amphidromus found there, Amphidromus banksi Butot, is quite different, the shells have a wide, white zone below the suture as in the Amphidromus atricallosus complex and the lower parts of the whorls are yellow, with or without narrow, wavy, reddish-brown flammulations. The original specimens in the Natural History Museum appear to be a form of Amphidromus perversus and it was described from South Borneo in the Bandjermassin District, but there are specimens in the Naturalis, Leiden from East Borneo. The flammulations above the periphery are reduced in number, possibly this may prove to be a subspecies, but not enough data are available. Amphidromus perversus perversus f. infrapictus von Martens,1867, was considered by Pilsbry to be identical with interruptus Müller,1774, at best it might be considered a slightly different stage in an almost continuous series of variations. Amphidromus perversus perversus f. infraviridis von Martens,1867, probably is a derivative of the Celebesian infrapictus, instead of flammulations and a basal purplish zone it has a pale green or greenish-yellow base which is only slightly darker than the greenish-yellow or citron-colored spire. It is most similar to typical perversus but differs in the basal portion. Amphidromus perversus perversus f. mitra von Martens,1867, is a variety from Bali. Amphidromus perversus perversus f. niveus P. & F. Sarasin,1899 is snow-white with a black varix and it is an albino perversus which is common in the Celebes and sporadically seen from Java and Borneo. Amphidromus perversus perversus f. obesus von Martens,1867, is a variety which probably can be equated with squat individuals of the typical perversus pattern. Amphidromus perversus perversus f. perversus Linnaeus,1758, is a yellow shell with black varix
Amphidromus perversus
–
Amphidromus perversus
37.
Cenozoic
–
The Cenozoic Era is the current and most recent of the three Phanerozoic geological eras, following the Mesozoic Era and covering the period from 66 million years ago to the present day. The Cenozoic is also known as the Age of Mammals, because of the mammals that dominated, such as Entelodont, Paraceratherium. The extinction of many large groups such as non-avian dinosaurs, Plesiosauria and Pterosauria allowed the mammals and birds to greatly diversify. Early in the Cenozoic, following the K-Pg event, the planet was dominated by relatively small fauna, including mammals, birds, reptiles. From a geological perspective, it did not take long for mammals, some flightless birds grew larger than humans. These species are referred to as terror birds, and were formidable predators. Mammals came to occupy almost every available niche, and some also grew very large, the Earths climate had begun a drying and cooling trend, culminating in the glaciations of the Pleistocene Epoch, and partially offset by the Paleocene-Eocene Thermal Maximum. The continents also began looking roughly familiar at this time and moved into their current positions. The Cenozoic is divided into three periods, the Paleogene, Neogene, and Quaternary, and seven epochs, the Paleocene, Eocene, Oligocene, Miocene, Pliocene, Pleistocene, and Holocene. The common use of epochs during the Cenozoic helps paleontologists better organize, there is also more detailed knowledge of this era than any other because of the relatively young, well-preserved rocks associated with it. The Paleogene spans from the extinction of dinosaurs,66 million years ago. It features three epochs, the Paleocene, Eocene and Oligocene, the Paleocene ranged from 66 million to 56 million years ago. The Paleocene is a point between the devastation that is the K-T extinction, to the rich jungles environment that is the Early Eocene. The Early Paleocene saw the recovery of the earth, the continents began to take their modern shape, but all the continents and subcontinent India were separated from each other. Afro-Eurasia was separated by the Tethys Sea, and the Americas were separated by the strait of Panama and this epoch featured a general warming trend, with jungles eventually reaching the poles. The oceans were dominated by sharks as the large reptiles that had once ruled became extinct, archaic mammals filled the world such as creodonts and early primates that evolved during the Mesozoic, and as a result, there was nothing over 10 kilograms. The Eocene Epoch ranged from 56 million years to 33.9 million years ago, in the Early-Eocene, life was small and lived in cramped jungles, much like the Paleocene. There was nothing over the weight of 10 kilograms, among them were early primates, whales and horses along with many other early forms of mammals
Cenozoic
–
Basilosaurus
Cenozoic
–
Animals of the Miocene (
Chalicotherium,
Hyenadon,
Entelodont...). Mammals are the dominant terrestrial vertebrates of the Cenozoic.
Cenozoic
–
Megafauna of the Pleistocene (
mammoths,
cave lions,
woolly rhino,
Megaloceros, American
horses)
38.
Spiral cleavage
–
In embryology, cleavage is the division of cells in the early embryo. The zygotes of many species undergo rapid cell cycles with no significant growth, the different cells derived from cleavage are called blastomeres and form a compact mass called the morula. Cleavage ends with the formation of the blastula, depending mostly on the amount of yolk in the egg, the cleavage can be holoblastic or meroblastic. The pole of the egg with the highest concentration of yolk is referred to as the pole while the opposite is referred to as the animal pole. Cleavage differs from other forms of division in that it increases the number of cells without increasing the mass. This means that each successive subdivision, the ratio of nuclear to cytoplasmic material increases. The rapid cell cycles are facilitated by maintaining levels of proteins that control cell cycle progression such as the cyclins. The processes of karyokinesis and cytokinesis work together to result in cleavage, the mitotic apparatus is made up of a central spindle and polar asters made up of polymers of tubulin protein called microtubules. The asters are nucleated by centrosomes and the centrosomes are organized by centrioles brought into the egg by the sperm as basal bodies, cytokinesis is mediated by the contractile ring made up of polymers of actin protein called microfilaments. Karyokinesis and cytokinesis are independent but spatially and temporally coordinated processes, while mitosis can occur in the absence of cytokinesis, cytokinesis requires the mitotic apparatus. The end of cleavage coincides with the beginning of zygotic transcription and this point is referred to as the midblastula transition and appears to be controlled by the nuclear, cytoplasmic ratio. Determinate cleavage is in most protostomes and it results in the developmental fate of the cells being set early in the embryo development. Each blastomere produced by early embryonic cleavage does not have the capacity to develop into a complete embryo, a cell can only be indeterminate if it has a complete set of undisturbed animal/vegetal cytoarchitectural features. It is characteristic of deuterostomes – when the cell in a deuterostome embryo divides. These holoblastic cleavage planes pass all the way through isolecithal zygotes during the process of cytokinesis, coeloblastula is the next stage of development for eggs that undergo these radial cleavaging. In holoblastic eggs, the first cleavage always occurs along the axis of the egg. From here, the arrangement of blastomeres can follow various patterns, due to different planes of cleavage. Bilateral The first cleavage results in bisection of the zygote into left, the following cleavage planes are centered on this axis and result in the two halves being mirror images of one another
Spiral cleavage
–
D quadrant specification through equal and unequal cleavage mechanisms. At the 4-cell stage of equal cleavage, the D macromere has not been specified yet. It will be specified after the formation of the third quartet of micromeres. Unequal cleavage occurs in two ways: asymmetric positioning of the mitotic spindle, or through the formation of a polar lobe (PL).
39.
Amphidromus
–
Amphidromus is a genus of air-breathing land snails, terrestrial pulmonate gastropod mollusks in the family Camaenidae. Amphidromus is a genus of arboreal pulmonate land snails, the shells of Amphidromus are relatively large, from one to three inches high, and colorful. The genus may be characterized as follows, It has brightly colored, elongate conic shells, the aperture is sublunate or auriform, without teeth or folds, height two-fifths to one-third that of shell. The peristome is expanded and reflected, sometimes thickened, parietal callus is weak to well-developed. The umbilicus is open or closed, color pattern is monochrome to variegated. The jaw is thin and weak with low flat ribs, the radula is with cusped teeth arranged in V-shaped rows and modified in typical arboreal pattern. The pallial region is sigmurethrous with very long, narrow kidney, genitalia are camaenid, with long seminal receptacle, and short penis with low insertion of retractor muscle. Comparatively little material has gathered by malacologists. Several species and forms were described before 1800, generally with inadequate locality data, at least two kinds — Amphidromus laevus and the form Amphidromus perversus f. aureus Martyn,1784 — still have not been reported from a precise locality. 19th century Many species and varieties were named during the first half of the nineteenth century, not until Eduard von Martens publication was there an effort to deal with the entire complex. This paper showed an amazing grasp of variation and problems of geographic distribution, hugh Fulton organized 142 specific and varietal names into eighteen species groups with 64 species. When the monograph Manual of Conchology of Henry Augustus Pilsbry appeared, the number of species had increased to 81, Pilsbrys study has remained the only illustrated monograph of the genus, and it is still indispensable for any serious study. 20th century Since 1900, the taxonomic studies on Amphidromus have been faunistic in scope. The papers of Paul Bartsch on the Philippine species, Bernhard Rensch on the Lesser Sunda Islands forms, potentially the most valuable contribution is that of Curt Haniel, who discussed the variation of Amphidromus contrarius and Amphidromus reflexilabris on Timor. Variations in color and form were well illustrated in a series of color plates, Adolf Michael Zilch listed type specimens in the Senckenberg Museum and illustrated many previously unfigured species. The literature contains many scattered descriptions of new forms and subspecies that appeared after 1900. Of the 309 names in the nomenclatural list,111 were published after Pilsbry, Frank Fortescue Laidlaw & Alan Solem recognized 74 species by name and considered that material from the Banda Islands probably represents an undescribed species. There are eleven species recognized by them that were described after the appearance of Pilsbrys monograph, study by Frank Fortescue Laidlaw & Alan Solem forms a supplement to Pilsbrys monograph with his extensive plates
Amphidromus
–
Amphidromus
40.
Haiti
–
Haiti, officially the Republic of Haiti and formerly called Hayti, is a country located on the island of Hispaniola in the Greater Antilles archipelago of the Caribbean Sea. It occupies the western three-eighths of the island, which it shares with the Dominican Republic, the region was originally inhabited by the indigenous Taíno people. Spain discovered the island on 5 December 1492 during the first voyage of Christopher Columbus across the Atlantic, when Columbus initially landed in Haiti, he had thought he had found India or Asia. On Christmas Day 1492, Columbus flagship the Santa Maria ran aground north of what is now Limonade, the island was named La Española and claimed by Spain, which ruled until the early 17th century. Competing claims and settlements by the French led to the portion of the island being ceded to France. The development of plantations, worked by slaves brought from Africa. Upon his death in a prison in France, he was succeeded by his lieutenant, Jean-Jacques Dessalines, the Haitian Revolution lasted just over a dozen years, and apart from Alexandre Pétion, the first President of the Republic, all the first leaders of government were former slaves. The Citadelle Laferrière is the largest fortress in the Americas, Henri Christophe – former slave and first king of Haiti, Henri I – built it to withstand a possible foreign attack. It has the lowest Human Development Index in the Americas, most recently, in February 2004, a coup détat originating in the north of the country forced the resignation and exile of President Jean-Bertrand Aristide. A provisional government took control with security provided by the United Nations Stabilization Mission in Haiti, the name Haïti comes from the indigenous Taíno language which was the native name given to the entire island of Hispaniola to mean, land of high mountains. The h is silent in French and the ï in Haïti, is a mark used to show that the second vowel is pronounced separately. In English, this rule for the pronunciation is often disregarded, the name Haïti was restored by Haitian revolutionary Jean-Jacques Dessalines as the official name of independent Saint-Domingue, as a tribute to the Amerindian predecessors. The Taíno name for the island was Haiti. The people had migrated over centuries into the Caribbean islands from South America, genetic studies show they were related to the Yanomami of the Amazon Basin. They also originated in Central and South America, after migrating to Caribbean islands, in the 15th century, the Taíno were pushed into the northeast Caribbean islands by the Caribs. In the Taíno societies of the Caribbean islands, the largest unit of organization was led by a cacique, or chief. The caciquedoms were tributary kingdoms, with payment consisting of harvests, Taíno cultural artifacts include cave paintings in several locations in the country. These have become symbols of Haiti and tourist attractions
Haiti
–
Burning of the town of
Cap-Français
Haiti
–
Flag
Haiti
–
Battle between
British troops in French service and the
Haitian rebels.
Haiti
–
Pétion and Dessalines swearing allegiance to one another before God; painting by
Guillon-Lethière
41.
Liguus virgineus
–
Liguus virgineus, also known as the Candy Cane Snail or the Virgin Liguus, is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Orthalicidae. Liguus virgineus is a species of the genus Liguus. In one such report circa 1989, a U. S. Air Force Sergeant reported finding a pair on a banana tree in his back yard while living in U. S. Government housing at Sigsbee Park in Key West, the two shells were positively identified as Liguus virgineus, but their live collection in Key West could not be verified. These sea snails live on trees and feed on moss, fungi, shells of Liguus virgineus can reach a length of 30–60 millimetres. These small shells are oval-conical shaped, thin but robust, shell surface is mooth and shiny. The background color of the shell is white or creamy-white, with thin bright spiral stripes of orange, purple, the aperture may be dark-grey or white-purple with scarlet lips. Shells of these land snails for years have been over-harvested for the craft trade. The destruction of the habitat and the commercial overcollecting could lead to the extinction of this species. Now harvesting and selling these shells is forbidden by the law, conchology Image of a live individual on Flickr
Liguus virgineus
–
Liguus virgineus
42.
Orthalicidae
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Orthalicidae are a family of tropical air-breathing land snails, terrestrial pulmonate gastropod mollusks are classified in the informal group Sigmurethra of the clade Stylommatophora. They are medium-sized to large snails, from about 3 cm to 9 cm in shell length, in former times, this family was often known as the Bulimulidae, but this term may also denote what today is the subfamily Bulimulinae. The subfamily Bulimulinae replaces the former family Bulimulidae Crosse & P. Fischer,1873, the Orthalicidae belong to the Orthalicoidea, a superfamily in the clade Sigmurethra. Like other stylommatophorans, the Sigmurethra belong to the suborder Eupulmonata, breure & Romero confirmed previous results from 2010, additionally they elevated Simpulopsini to Simpulopsidae. & Janssen R. Die Typen und Typoide des Natur-Museums Senckenberg,84, Mollusca, Gastropoda, Pulmonata, Orthalicoidea, revista Peruana de Biología 17, 53-57. Revista Peruana de Biología 16, 51-56
Orthalicidae
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Orthalicidae
43.
Hawaii
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Hawaii is the 50th and most recent state to have joined the United States of America, having received statehood on August 21,1959. Hawaii is the only U. S. state located in Oceania and it is the northernmost island group in Polynesia, occupying most of an archipelago in the central Pacific Ocean. Hawaii is the only U. S. state not located in the Americas, the state encompasses nearly the entire volcanic Hawaiian archipelago, which comprises hundreds of islands spread over 1,500 miles. At the southeastern end of the archipelago, the eight main islands are—in order from northwest to southeast, Niʻihau, Kauaʻi, Oʻahu, Molokaʻi, Lānaʻi, Kahoʻolawe, Maui, and the Island of Hawaiʻi. The last is the largest island in the group, it is called the Big Island or Hawaiʻi Island to avoid confusion with the state or archipelago. The archipelago is physiographically and ethnologically part of the Polynesian subregion of Oceania, Hawaii has over a million permanent residents, along with many visitors and U. S. military personnel. Its capital is Honolulu on the island of Oʻahu, Hawaii is the 8th-smallest and the 11th-least populous, but the 13th-most densely populated of the fifty U. S. states. It is the state with an Asian plurality. The states coastline is about 750 miles long, the fourth longest in the U. S. after the coastlines of Alaska, Florida, the state of Hawaii derives its name from the name of its largest island, Hawaiʻi. A common Hawaiian explanation of the name of Hawaiʻi is that was named for Hawaiʻiloa and he is said to have discovered the islands when they were first settled. The Hawaiian language word Hawaiʻi is very similar to Proto-Polynesian *Sawaiki, cognates of Hawaiʻi are found in other Polynesian languages, including Māori, Rarotongan and Samoan. According to linguists Pukui and Elbert, lsewhere in Polynesia, Hawaiʻi or a cognate is the name of the underworld or of the home, but in Hawaii. A somewhat divisive political issue arose in 1978 when the Constitution of the State of Hawaii added Hawaiian as an official state language. The title of the constitution is The Constitution of the State of Hawaii. Article XV, Section 1 of the Constitution uses The State of Hawaii, diacritics were not used because the document, drafted in 1949, predates the use of the okina and the kahakō in modern Hawaiian orthography. The exact spelling of the name in the Hawaiian language is Hawaiʻi. In the Hawaii Admission Act that granted Hawaiian statehood, the government recognized Hawaii as the official state name. Official government publications, department and office titles, and the Seal of Hawaii use the spelling with no symbols for glottal stops or vowel length
Hawaii
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Hawaii from space, January 26, 2014
Hawaii
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Flag
Hawaii
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Nā Pali coast, Kaua ʻ i
Hawaii
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The main islands and undersea terrain of Hawaii
44.
Achatinella
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Oʻahu tree snails, genus Achatinella, form a large genus of colorful, tropical, tree-living, air-breathing, land snails, arboreal pulmonate gastropod mollusks in the family Achatinellidae. This genus of snails is endemic to Hawaii, and all extant species are endangered. They were once abundant, and were mentioned extensively in Hawaiian folklore and songs, many of these arboreal snails are sinistral or left-handed in their spiral shell coiling, whereas most gastropod shells are dextral. There are 41 species of Oʻahu tree snail endemic to Hawaiian island of Oʻahu, all are endangered, there being only about hundred individuals of each species left. All 41 species are listed under United States federal legislation as endangered, the IUCN lists a number of these species as extinction and the remainder as critically endangered. In many cases the introduced and highly predatory snail Euglandina rosea has been involved in the extinctions, Oʻahu tree snails are diverse in patterns, colors, and shapes, but all average about 0.75 in in length. Most have smooth glossy, and oblong or ovate shells which show a variety of colors, including yellow, orange, red, brown, green, gray, black, there are three recognized subgenera within the genus Achatinella. Subgenera are distinguished according to shells characteristics only, Shell color is in spiral bands or streaks in the direction of the growth lines. The lip is simple or thickened within and sometimes slightly expanding, the columella bears a strong callous fold. Type species of the genus Achatinella is Achatinella apexfulva, subgenus Bulimella Pfeiffer,1854, Shell shape is oblong-conic or ovate. The spire is obtuse, rounded or convexly-conic near the apex, the outer lip is thickened by a strong callous rib within the aperture. Type species of the subgenus Bulimella is Achatinella byronii Newcomb, subgenus Achatinellastrum Pfeiffer,1854, The shell is imperforate, ovate-conic or oblong-conic and smooth. The embryonic whorls are not flattened, the outer lip is thin or only slightly thickened within the apex but not expanded. These are the most generally distributed of the Achatinella species and show an area of intergrading color patterns. Type species of the subgenus Achatinellastrum is Achatinella stewartii, currently they are only found in mountainous dry to moist forests and shrublands above 1,300 ft. These tree snails are nocturnal, and feed by grazing fungus which grows on the surface of plant leaves. In captivity Achatinella feed on growing on leaves of Metrosideros polymorpha. They also feed on cornstarch, which can be spread in terraria with water, in captivity, cuttlebone is used as a source for calcium
Achatinella
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O ʻ ahu tree snail
Achatinella
Achatinella
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O'ahu tree snail shells collected ca. 1933 at an elevation of 1500 feet on Waialae Ridge in
Waialae Country Club,
Honolulu, Hawaii.
Achatinella
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Euglandina rosea
45.
Achatinellidae
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Achatinellidae is a family of tropical air-breathing land snails, terrestrial pulmonate gastropod mollusks in the superfamily Achatinelloidea. This is the family in the superfamily Achatinelloidea. This family of snails occurs widely in the Pacific islands and they are at their most diverse in the Hawaiian group
Achatinellidae
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Achatinellidae
Achatinellidae
46.
Partula (gastropod)
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Partula is a genus of air-breathing tropical land snails, terrestrial pulmonate gastropod mollusks in the family Partulidae. Many species of Partula are known under the common names Polynesian tree snail. Partulids are spread over 5,000 square miles of Pacific Ocean islands, once used as decorative items in Polynesian ceremonial wear and jewelry, these small snails gained the attention of science when Dr. What happened to the partulids of the island of Tahiti is a demonstration of the deleterious effects of attempted biological control. After an infestation of the introduced giant African land snails, the carnivorous Florida rosy wolfsnail was introduced into Tahiti in an attempt to combat the African species. The wolfsnail chose instead to hunt and eat members of the nearly 76 species of Partula that were endemic to Tahiti, several scientists recognized what was going on, and were able to save 12 species prior to their becoming extinct. Today, the Zoological Society of London runs the Partula Programme Consortium which maintains a breeding program in the United Kingdom, France. The 2008 IUCN Red List of Threatened Species contains 15 critically endangered,11 extinct in the wild and 48 extinct Partula species, the IUCN Red List of Threatened Species version 2009.2 contains 13 critically endangered,11 extinct in the wild and 51 extinct Partula species. The IUCN Red List of Threatened Species version 2015-4 contains 83 Partula species and this article incorporates public domain text from the reference. Studies on the variation, distribution and evolution of the genus Partula, carnegie Institution of Washington,228, 1-311. Studies on the variation, distribution and evolution of the genus Partula, the species of the Mariana Islands, Guam and Saipan. Carnegie Institution of Washington, 228a, 1-116, studies on the variation, distribution and evolution of the genus Partula. Carnegie Institution of Washington,410, 1-335, coote, T. Pearce-Kelly, P. ó Foighil, D. Tahitian tree snail mitochondrial clades survived recent mass extirpation. Partula evolution, diversity and conservation Partula Pages
Partula (gastropod)
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Black-and-white photo taken in July 1920 in
Saipan, showing numerous Partula snails on the underside of a single leaf of
Caladium
Partula (gastropod)
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Partula
47.
Partulidae
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Partulidae is a family of air-breathing land snails, terrestrial gastropod mollusks in the superfamily Partuloidea. The family is endemic to Pacific islands, Partulidae is divided into five genera, Eua has four species, confined to Tonga and Samoa. Partula has about 100 species, distributed from New Guinea to the Society Islands, samoana has about 23 species, distributed in Polynesia and the Mariana Islands. Most Partulidae species have declined since 1974 and a large proportion are extinct. The main threat to their survival has been the introduction of the predatory snail Euglandina rosea, Partulidae evolution, diversity and conservation Partula Pages
Partulidae
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Partulidae
Laidlaw F. F. & Solem A. (1961). "The land snail genus Amphidromus: a synoptic catalogue". Fieldiana Zoology 41(4): 505-720.
