Pinus roxburghii known as chir pine or longleaf Indian pine, is a species of pine. It is native to the Himalayas, was named after William Roxburgh; the native range extends from Tibet and Afghanistan through Pakistan, across northern India in Jammu and Kashmir, Himachal Pradesh, Sikkim, Arunachal Pradesh), Nepal and Bhutan, to Myanmar. It occurs at lower altitudes than other pines in the Himalaya, from 500–2,000 m up to 2,300 m; the other Himalayan pines are Pinus wallichiana, Pinus bhutanica, Pinus armandii, Pinus gerardiana and Pinus densata, Pinus kesiya. Pinus roxburghii is a large tree reaching 30–50 m with a trunk diameter of up to 2 m, exceptionally 3 m; the bark is red-brown and fissured at the base of the trunk and flaky in the upper crown. The leaves are needle-like, in fascicles of three slender, 20–35 cm long, distinctly yellowish green; the cones are ovoid conic, 12–24 cm long and 5–8 cm broad at the base when closed, green at first, ripening glossy chestnut-brown when 24 months old.
They open over the next year or so, or after being heated by a forest fire, to release the seeds, opening to 9–18 cm broad. The seeds are 8–9 mm long, with a 40 mm wing, are wind-dispersed. Pinus roxburghii is related to Pinus canariensis, Pinus brutia and Pinus pinaster, which all share many features with it, it is a non-variable species, with constant morphology over the entire range. The accumulating carpet of needles on the forest floor under these trees makes it unsuitable for many common plants and trees to grow; the most common trees which are able to grow in this environment are Rhododendron, banj oak and trees from the Ericaceae families. This could be due to the relative immunity from fire that the thick bark of these species gives them; the Himalayan stinging nettle is another plant. The caterpillars of the moth Batrachedra silvatica are not known from foodplants other than chir pine; the white-bellied heron, a large heron is known to roost in chir pine. Chir pine is planted for timber in its native area, being one of the most important trees in forestry in northern Pakistan and Nepal.
For local building purposes, the wood of this tree is the least preferred, as it is the weakest and most prone to decay when compared with other conifers. However, in most low altitude regions, there is no other choice, except for the fact that these being tropical latitudes there are other trees at lower altitudes; when this species of pine tree reaches a large girth, the bark forms flat patches which can be broken off in chunks of about 52 cm2 by 51 mm thick. It has a layered structure like plywood; the locals use this carvable bark to make useful items like lids for vessels. Blacksmiths of that region use this bark as the fuel for their furnaces. Old trees which die from fire or drought, undergo some metamorphosis in their wood due to the crystallization of the resin inside the heart wood; this makes the wood become brightly coloured and aromatic with a brittle, glassy feel. This form of wood known as jhukti by the locals is easy to ignite, they use it for starting fires and for lighting, as a small piece of this burns for a long time.
Of all the conifer species in the area, only this one seems to be ideal for that purpose. Every autumn, the dried needles of this tree forms a dense carpet on the forest floor, which the locals gather in large bundles to serve as bedding for their cattle, for the year round; the green needles are used to make tiny hand brooms. The locals of the Jaunsar-Bawar region of Uttarakhand have several uses for this tree, known in the local dialect as salli, it is occasionally used as an ornamental tree, planted in parks and gardens in hot dry areas, where its heat and drought tolerance is valued. Pinus roxburghii contains large amounts of taxifolin, it is tapped commercially for resin. On distillation, the resin yieds an essential oil known as turpentine, non-volatile rosin; the proportion of rosin and turpentine oil in chir pine is 75% and 22% with 3% losses, etc. The turpentine is chiefly used as a solvent in pharmaceutical preparations, perfume industry, in manufacture of synthetic pine oil, disinfectants and denaturants.
It is one of the most important basic raw materials for the synthesis of terpene chemicals which are used in a wide variety of industries such as adhesives and rubber, etc. Chir pine rosin is principally used in paper, cosmetics, varnish and polish industries. Besides these, other uses include manufacture of linoleum, explosives and disinfectants, as a flux in soldering, in brewing and in mineral beneficiation as a frothing agent. Presently, India imports resin, far superior in quality as well as cheaper than the indigenous one. Quality of resin depends on the pinene content. Imported resin contains 75 -- 95 % pinenes. Retapping Chir Pines the Environmentally Friendly Way Plants For A Future: Chir Pine Flora Indica: P. longifolia, III, p. 651
The Silurian is a geologic period and system spanning 24.6 million years from the end of the Ordovician Period, at 443.8 million years ago, to the beginning of the Devonian Period, 419.2 Mya. The Silurian is the shortest period of the Paleozoic Era; as with other geologic periods, the rock beds that define the period's start and end are well identified, but the exact dates are uncertain by several million years. The base of the Silurian is set at a series of major Ordovician–Silurian extinction events when 60% of marine species were wiped out. A significant evolutionary milestone during the Silurian was the diversification of jawed fish and bony fish. Multi-cellular life began to appear on land in the form of small, bryophyte-like and vascular plants that grew beside lakes and coastlines, terrestrial arthropods are first found on land during the Silurian. However, terrestrial life would not diversify and affect the landscape until the Devonian; the Silurian system was first identified by British geologist Roderick Murchison, examining fossil-bearing sedimentary rock strata in south Wales in the early 1830s.
He named the sequences for a Celtic tribe of Wales, the Silures, inspired by his friend Adam Sedgwick, who had named the period of his study the Cambrian, from the Latin name for Wales. This naming does not indicate any correlation between the occurrence of the Silurian rocks and the land inhabited by the Silures. In 1835 the two men presented a joint paper, under the title On the Silurian and Cambrian Systems, Exhibiting the Order in which the Older Sedimentary Strata Succeed each other in England and Wales, the germ of the modern geological time scale; as it was first identified, the "Silurian" series when traced farther afield came to overlap Sedgwick's "Cambrian" sequence, provoking furious disagreements that ended the friendship. Charles Lapworth resolved the conflict by defining a new Ordovician system including the contested beds. An early alternative name for the Silurian was "Gotlandian" after the strata of the Baltic island of Gotland; the French geologist Joachim Barrande, building on Murchison's work, used the term Silurian in a more comprehensive sense than was justified by subsequent knowledge.
He divided the Silurian rocks of Bohemia into eight stages. His interpretation was questioned in 1854 by Edward Forbes, the stages of Barrande, F, G and H, have since been shown to be Devonian. Despite these modifications in the original groupings of the strata, it is recognized that Barrande established Bohemia as a classic ground for the study of the earliest fossils; the Llandovery Epoch lasted from 443.8 ± 1.5 to 433.4 ± 2.8 mya, is subdivided into three stages: the Rhuddanian, lasting until 440.8 million years ago, the Aeronian, lasting to 438.5 million years ago, the Telychian. The epoch is named for the town of Llandovery in Wales; the Wenlock, which lasted from 433.4 ± 1.5 to 427.4 ± 2.8 mya, is subdivided into the Sheinwoodian and Homerian ages. It is named after Wenlock Edge in England. During the Wenlock, the oldest-known tracheophytes of the genus Cooksonia, appear; the complexity of later Gondwana plants like Baragwanathia, which resembled a modern clubmoss, indicates a much longer history for vascular plants, extending into the early Silurian or Ordovician.
The first terrestrial animals appear in the Wenlock, represented by air-breathing millipedes from Scotland. The Ludlow, lasting from 427.4 ± 1.5 to 423 ± 2.8 mya, comprises the Gorstian stage, lasting until 425.6 million years ago, the Ludfordian stage. It is named for the town of Ludlow in England; the Přídolí, lasting from 423 ± 1.5 to 419.2 ± 2.8 mya, is the final and shortest epoch of the Silurian. It is named after one locality at the Homolka a Přídolí nature reserve near the Prague suburb Slivenec in the Czech Republic. Přídolí is the old name of a cadastral field area. In North America a different suite of regional stages is sometimes used: Cayugan Lockportian Tonawandan Ontarian Alexandrian In Estonia the following suite of regional stages is used: Ohessaare stage Kaugatuma stage Kuressaare stage Paadla stage Rootsiküla stage Jaagarahu stage Jaani stage Adavere stage Raikküla stage Juuru stage With the supercontinent Gondwana covering the equator and much of the southern hemisphere, a large ocean occupied most of the northern half of the globe.
The high sea levels of the Silurian and the flat land resulted in a number of island chains, thus a rich diversity of environmental settings. During the Silurian, Gondwana continued a slow southward drift to high southern latitudes, but there is evidence that the Silurian icecaps were less extensive than those of the late-Ordovician glaciation; the southern continents remained united during this period. The melting of icecaps and glaciers contributed to a rise in sea level, recognizable from the fact that Silurian sediments overlie eroded Ordovician sediments, forming an unconformity; the continents of Avalonia and Laurentia drifted together near the equator, starting the formation of a second supercontinent known as Euramerica. When the proto-Europe coll
A sporangium is an enclosure in which spores are formed. It can be multicellular. All plants and many other lineages form sporangia at some point in their life cycle. Sporangia can produce spores by mitosis, but in nearly all land plants and many fungi, sporangia are the site of meiosis and produce genetically distinct haploid spores. In some phyla of fungi, the sporangium plays a role in asexual reproduction, may play an indirect role in sexual reproduction; the sporangium contains haploid nuclei and cytoplasm. Spores are formed in the sporangiophore by encasing each haploid nucleus and cytoplasm in a tough outer membrane. During asexual reproduction, these spores are dispersed via germinate into haploid hyphae. Although sexual reproduction in fungi varies between phyla, for some fungi the sporangium plays an indirect role in sexual reproduction. For Zygomycota, sexual reproduction occurs when the haploid hyphae from two individuals join to form a zygosporangium in response to unfavorable conditions.
The haploid nuclei within the zygosporangium fuse into diploid nuclei. When conditions improve the zygosporangium germinates, undergoes meiosis and produces a sporangium, which releases spores. In mosses and hornworts, an unbranched sporophyte produces a single sporangium, which may be quite complex morphologically. Most non-vascular plants, as well as many lycophytes and most ferns, are homosporous; some bryophytes, most lycophytes, some ferns are heterosporous. These plants produce microspores and megaspores, which give rise to gametophytes that are functionally male or female, respectively. In some cases, both kinds of spores are produced in the same sporangium, may develop together as part of a spore tetrad. However, in most heterosporous plants there are two kinds of sporangia, termed microsporangia and megasporangia. A few ferns and some lycophytes are heterosporous with two kinds of sporangia, as are all the seed plants. Sporangia can associated with leaves. In ferns, sporangia are found on the abaxial surface of the leaf and are densely aggregated into clusters called sori.
Sori may be covered by a structure called an indusium. Some ferns have their sporangia scattered along reduced leaf segments or along the margin of the leaf. Lycophytes, in contrast, bear their sporangia on the adaxial surface of leaves or laterally on stems. Leaves that bear sporangia are called sporophylls. If the plant is heterosporous, the sporangia-bearing leaves are distinguished as either microsporophylls or megasporophylls. In seed plants, sporangia are located within strobili or flowers. Cycads form their microsporangia on microsporophylls. Megasporangia are formed within ovules, which are borne on megasporophylls, which are aggregated into strobili on separate plants. Conifers bear their microsporangia on microsporophylls aggregated into papery pollen strobili, the ovules, are located on modified stem axes forming compound ovuliferous cone scales. Flowering plants contain microsporangia in the anthers of stamens and megasporangia inside ovules inside ovaries. In all seed plants, spores are produced by meiosis and develop into gametophytes while still inside the sporangium.
The microspores become microgametophytes. The megaspores become megagametophytes. Categorized based on developmental sequence and leptosporangia are differentiated in the vascular plants. In a leptosporangium, found only in ferns, development involves a single initial cell that becomes the stalk and spores within the sporangium. There are around 64 spores in a leptosporangium. In a eusporangium, characteristic of all other vascular plants and some primitive ferns, the initials are in a layer. A eusporangium is larger, its wall is multi-layered. Although the wall may be stretched and damaged, resulting in only one cell-layer remaining. A cluster of sporangia that have become fused in development is called a synangium; this structure is most prominent in Psilotum and Marattiaceae such as Christensenia and Marattia. A columella is a sterile structure that supports the sporangium. In fungi, the columella, which may be branched or unbranched, may be of host origin. Secotium species have a simple, unbranched columella, while in Gymnoglossum species, the columella is branched.
In some Geastrum species, the columella appears as an extension of the stalk into the spore mass. Microsporangium Archegonium Antheridium Spore formation
Glossary of plant morphology
This page provides a glossary of plant morphology. Botanists and other biologists who study plant morphology use a number of different terms to classify and identify plant organs and parts that can be observed using no more than a handheld magnifying lens; this page provides help in understanding the numerous other pages describing plants by their various taxa. The accompanying page—Plant morphology—provides an overview of the science of the external form of plants. There is an alphabetical list: Glossary of botanical terms. In contrast, this page deals with botanical terms in a systematic manner, with some illustrations, organized by plant anatomy and function in plant physiology; this glossary includes terms that deal with vascular plants flowering plants. Non-vascular plants, with their different evolutionary background, tend to have separate terminology. Although plant morphology is integrated with plant anatomy, the former became the basis of the taxonomic description of plants that exists today, due to the few tools required to observe.
Many of these terms date back including Theophrastus. Thus, they have Greek or Latin roots; these terms have been modified and added to over the years, different authorities may not always use them the same way. This page has two parts: The first deals with general plant terms, the second with specific plant structures or parts. Abaxial – located on the side facing away from the axis. Adaxial – located on the side facing towards the axis. Dehiscent – opening at maturity Gall – outgrowth on the surface caused by invasion by other lifeforms, such as parasites Indehiscent – not opening at maturity Reticulate – web-like or network-like Striated – marked by a series of lines, grooves, or ridges Tesselate – marked by a pattern of polygons rectangles Wing – any flat surfaced structure emerging from the side or summit of an organ. Plant habit refers to the overall shape of a plant, it describes a number of components such as stem length and development, branching pattern, texture. While many plants fit neatly into some main categories, such as grasses, shrubs, or trees, others can be more difficult to categorise.
The habit of a plant provides important information about its ecology: that is, how it has adapted to its environment. Each habit indicates a different adaptive strategy. Habit is associated with the development of the plant; as such, it may change as the plant is more properly called its growth habit. In addition to shape, habit indicates plant structure; each plant commences its growth as a herbaceous plant. Plants that remain herbaceous are shorter and seasonal, dying back at the end of their growth season. Woody plants (such as trees and woody vines will acquire woody tissues, which provide strength and protection for the vascular system, they tend to be tall and long lived; the formation of woody tissue is an example of secondary growth, a change in existing tissues, in contrast to primary growth that creates new tissues, such as the elongating tip of a plant shoot. The process of wood formation is commonest in the Spermatophytes and has evolved independently a number of times; the roots may lignify, aiding in the role of supporting and anchoring tall plants, may be part of a descriptor of the plant's habit.
Plant habit can refer to whether the plant possesses any specialised systems for the storage of carbohydrates or water, allowing the plant to renew its growth after an unfavourable period. Where the amount of water stored is high, the plant is referred to as a succulent; such specialised plant parts may arise from the roots. Examples include plants growing in unfavourable climates dry climates where storage is intermittent depending on climatic conditions, those adapted to surviving fires and regrowing from the soil afterwards; some types of plant habit include: Herbaceous plants: A plant whose structures above the surface of the soil, vegetative or reproductive, die back at the end of the annual growing season, never become woody. While these structures are annual in nature, the plant itself may be biannual, or perennial. Herbaceous plants that survive for more than one season possess underground storage organs, thus are referred to as geophytes. Terms used in describing plant habit, include: Acaulescent – the leaves and inflorescence rise from the ground, appear to have no stem.
They are known as rosette forms, some of the many conditions that result from short internodes (i.e. close distances between nodes on the plant stem. See radical, where leaves arise without stems. Acid plant – plants with acid saps due to the production of ammonium salts Acme – the time when the plant or population has its maximum vigor. Actinomorphic – parts of plants that are radially symmetrical in arrangement. Arborescent – growing into a tree-like habit with a single woody stem. Ascending – growing uprightly, in an upward direction. Assurgent – growth ascending. Branching – dividing into multiple smaller segments. Caducous – falling away early. Caulescent – with a well-developed stem above ground. Cespitose – forming dense tufts applied to small plants growing into mats, tufts, or clumps. Creeping – growing along the ground and producing roots at intervals along the surface. Deciduous – falling away after its function is completed. Decumbent – growth starts off prostrate and the ends turn upr
Lycopodiopsida is a class of herbaceous vascular plants known as the clubmosses and firmosses. They have dichotomously branching stems bearing simple leaves without ligules and reproduce by means of spores borne in sporangia at the bases of the leaves. Traditionally, the group included the spikemosses and the quillworts but because these groups have leaves with ligules and reproduce using spores of two different sizes, both are now placed into another class, Isoetopsida that includes the extinct Lepidodendrales; these groups, together with the horsetails are referred to informally as fern allies. The class Lycopodiopsida as interpreted here contains a single living order, the Lycopodiales, a single extinct order, the Drepanophycales; the classification of this group has been unsettled in recent years and a consensus has yet to emerge. Older classifications took a broad definition of the genus Lycopodium that included all the species of Lycopodiales; the trend in recent years has been to define Lycopodium more narrowly and to classify the other species into several genera, an arrangement, supported by both morphological and molecular data and adopted in numerous revisions and flora treatments.
Starting from the four genera accepted by Øllgaard, a study based on chloroplast DNA produced the cladogram shown below, confirming the monophyly of the four genera, their distance from Isoetes. The genera fall into two distinct clades, but there is, as yet, no consensus as to whether to recognize them in a single family, Lycopodiaceae, or to separate them into two families: a more narrowly defined Lycopodiaceae and Huperziaceae; the family Lycopodiaceae, as narrowly defined, comprises the extant genus, which includes the wolf's-foot clubmoss, Lycopodium clavatum, ground-pine, Lycopodium obscurum, southern ground-cedar, Lycopodium digitatum, other species. Included are species of Lycopodiella, such as the bog clubmoss, Lycopodiella inundata. Most of the Lycopodium species favor acidic, upland sites, whereas most of the Lycopodiella favor acidic, boggy sites; the other major group, the family Huperziaceae, are known as the firmosses. This group includes the genus Huperzia, such as the shining firmoss, Huperzia lucidula, the rock firmoss, Huperzia porophila, the northern firmoss, Huperzia selago.
This group includes the odd, tuberous Australasian plant Phylloglossum, which was, until thought to be only remotely related to the clubmosses. However, as the cladogram above shows, it is related to the genus Huperzia; the genera Huperzia and Lycopodium are among the plants in this group with non-photosynthetic subterranean gametophytes. Lycopodium powder, the dried spores of the common clubmoss, was used in Victorian theater to produce flame-effects. A blown cloud of spores burned and brightly, but with little heat. Spikemoss, Selaginella Isoetopsida
The Neogene is a geologic period and system that spans 20.45 million years from the end of the Paleogene Period 23.03 million years ago to the beginning of the present Quaternary Period 2.58 Mya. The Neogene is sub-divided into two epochs, the earlier Miocene and the Pliocene; some geologists assert that the Neogene cannot be delineated from the modern geological period, the Quaternary. The term "Neogene" was coined in 1853 by the Austrian palaeontologist Moritz Hörnes. During this period and birds continued to evolve into modern forms, while other groups of life remained unchanged. Early hominids, the ancestors of humans, appeared in Africa near the end of the period; some continental movement took place, the most significant event being the connection of North and South America at the Isthmus of Panama, late in the Pliocene. This cut off the warm ocean currents from the Pacific to the Atlantic Ocean, leaving only the Gulf Stream to transfer heat to the Arctic Ocean; the global climate cooled over the course of the Neogene, culminating in a series of continental glaciations in the Quaternary Period that follows.
In ICS terminology, from upper to lower: The Pliocene Epoch is subdivided into 2 ages: Piacenzian Age, preceded by Zanclean AgeThe Miocene Epoch is subdivided into 6 ages: Messinian Age, preceded by Tortonian Age Serravallian Age Langhian Age Burdigalian Age Aquitanian AgeIn different geophysical regions of the world, other regional names are used for the same or overlapping ages and other timeline subdivisions. The terms Neogene System and upper Tertiary System describe the rocks deposited during the Neogene Period; the continents in the Neogene were close to their current positions. The Isthmus of Panama formed, connecting South America; the Indian subcontinent continued forming the Himalayas. Sea levels fell, creating land bridges between Africa and Eurasia and between Eurasia and North America; the global climate became seasonal and continued an overall drying and cooling trend which began at the start of the Paleogene. The ice caps on both poles began to grow and thicken, by the end of the period the first of a series of glaciations of the current Ice Age began.
Marine and continental flora and fauna have a modern appearance. The reptile group Choristodera became extinct in the early part of the period, while the amphibians known as Allocaudata disappeared at the end. Mammals and birds continued to be the dominant terrestrial vertebrates, took many forms as they adapted to various habitats; the first hominins, the ancestors of humans, may have appeared in southern Europe and migrated into Africa. In response to the cooler, seasonal climate, tropical plant species gave way to deciduous ones and grasslands replaced many forests. Grasses therefore diversified, herbivorous mammals evolved alongside it, creating the many grazing animals of today such as horses and bison. Eucalyptus fossil leaves occur in the Miocene of New Zealand, where the genus is not native today, but have been introduced from Australia; the Neogene traditionally ended at the end of the Pliocene Epoch, just before the older definition of the beginning of the Quaternary Period. However, there was a movement amongst geologists to include ongoing geological time in the Neogene, while others insist the Quaternary to be a separate period of distinctly different record.
The somewhat confusing terminology and disagreement amongst geologists on where to draw what hierarchical boundaries is due to the comparatively fine divisibility of time units as time approaches the present, due to geological preservation that causes the youngest sedimentary geological record to be preserved over a much larger area and to reflect many more environments than the older geological record. By dividing the Cenozoic Era into three periods instead of seven epochs, the periods are more comparable to the duration of periods in the Mesozoic and Paleozoic eras; the International Commission on Stratigraphy once proposed that the Quaternary be considered a sub-era of the Neogene, with a beginning date of 2.58 Ma, namely the start of the Gelasian Stage. In the 2004 proposal of the ICS, the Neogene would have consisted of the Miocene and Pliocene epochs; the International Union for Quaternary Research counterproposed that the Neogene and the Pliocene end at 2.58 Ma, that the Gelasian be transferred to the Pleistocene, the Quaternary be recognized as the third period in the Cenozoic, citing key changes in Earth's climate and biota that occurred 2.58 Ma and its correspondence to the Gauss-Matuyama magnetostratigraphic boundary.
In 2006 ICS and INQUA reached a compromise that made Quaternary a subera, subdividing Cenozoic into the old classical Tertiary and Quaternary, a compromise, rejected by International Union of Geological Sciences because it split both Neogene and Pliocene in two. Following formal discussions at the 2008 International Geological Congress in Oslo, the ICS decided in May 2009 to make the Quaternary the youngest period of the Cenozoic Era with its base at 2.58 Mya and including the Gelasian age, considered part of the Neogene Period and Pliocene Epoch. Thus the Neogene Period ends bounding the succeeding Quaternary Period at 2.58 Mya. "Digital Atlas of Neogene Life for the Southeastern United States". San Jose State University. Archived from the original on 2013-04-23. Retrieved 21 September 2018
The Triassic is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.9 million years ago, to the beginning of the Jurassic Period 201.3 Mya. The Triassic is the shortest period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished. Therapsids and archosaurs were the chief terrestrial vertebrates during this time. A specialized subgroup of archosaurs, called dinosaurs, first appeared in the Late Triassic but did not become dominant until the succeeding Jurassic Period; the first true mammals, themselves a specialized subgroup of therapsids evolved during this period, as well as the first flying vertebrates, the pterosaurs, like the dinosaurs, were a specialized subgroup of archosaurs. The vast supercontinent of Pangaea existed until the mid-Triassic, after which it began to rift into two separate landmasses, Laurasia to the north and Gondwana to the south.
The global climate during the Triassic was hot and dry, with deserts spanning much of Pangaea's interior. However, the climate became more humid as Pangaea began to drift apart; the end of the period was marked by yet another major mass extinction, the Triassic–Jurassic extinction event, that wiped out many groups and allowed dinosaurs to assume dominance in the Jurassic. The Triassic was named in 1834 by Friedrich von Alberti, after the three distinct rock layers that are found throughout Germany and northwestern Europe—red beds, capped by marine limestone, followed by a series of terrestrial mud- and sandstones—called the "Trias"; the Triassic is separated into Early and Late Triassic Epochs, the corresponding rocks are referred to as Lower, Middle, or Upper Triassic. The faunal stages from the youngest to oldest are: During the Triassic all the Earth's land mass was concentrated into a single supercontinent centered more or less on the equator and spanning from pole to pole, called Pangaea.
From the east, along the equator, the Tethys sea penetrated Pangaea, causing the Paleo-Tethys Ocean to be closed. In the mid-Triassic a similar sea penetrated along the equator from the west; the remaining shores were surrounded by the world-ocean known as Panthalassa. All the deep-ocean sediments laid down during the Triassic have disappeared through subduction of oceanic plates; the supercontinent Pangaea was rifting during the Triassic—especially late in that period—but had not yet separated. The first nonmarine sediments in the rift that marks the initial break-up of Pangaea, which separated New Jersey from Morocco, are of Late Triassic age. S. these thick sediments comprise the Newark Group. Because a super-continental mass has less shoreline compared to one broken up, Triassic marine deposits are globally rare, despite their prominence in Western Europe, where the Triassic was first studied. In North America, for example, marine deposits are limited to a few exposures in the west, thus Triassic stratigraphy is based on organisms that lived in lagoons and hypersaline environments, such as Estheria crustaceans.
At the beginning of the Mesozoic Era, Africa was joined with Earth's other continents in Pangaea. Africa shared the supercontinent's uniform fauna, dominated by theropods and primitive ornithischians by the close of the Triassic period. Late Triassic fossils are more common in the south than north; the time boundary separating the Permian and Triassic marks the advent of an extinction event with global impact, although African strata from this time period have not been studied. During the Triassic peneplains are thought to have formed in what is now southern Sweden. Remnants of this peneplain can be traced as a tilted summit accordance in the Swedish West Coast. In northern Norway Triassic peneplains may have been buried in sediments to be re-exposed as coastal plains called strandflats. Dating of illite clay from a strandflat of Bømlo, southern Norway, have shown that landscape there became weathered in Late Triassic times with the landscape also being shaped during that time. At Paleorrota geopark, located in Rio Grande do Sul, the Santa Maria Formation and Caturrita Formations are exposed.
In these formations, one of the earliest dinosaurs, Staurikosaurus, as well as the mammal ancestors Brasilitherium and Brasilodon have been discovered. The Triassic continental interior climate was hot and dry, so that typical deposits are red bed sandstones and evaporites. There is no evidence of glaciation near either pole. Pangaea's large size limited the moderating effect of the global ocean; the strong contrast between the Pangea supercontinent and the global ocean triggered intense cross-equatorial monsoons. The Triassic may have been a dry period, but evidence exists that it was punctuated by several episodes of increased rainfall in tropical and subtropical latitudes of the Tethys Sea and its surrounding land. Sediments and fossils suggestive of a more humid climate are known from the Anisian to Ladinian of the Tethysian domain, from the Carnian and Rhaetian of a larger area that includes the Boreal domain, the North