The Palpimanoidea or palpimanoids, also known as assassin spiders, are a group of araneomorph spiders, originally treated as a superfamily. As with many such groups, its circumscription has varied. As of September 2018, the following five families were included:Archaeidae
Huttoniidae
Mecysmaucheniidae
Palpimanidae
Stenochilidae
Palpimanoidea
Zephyrarchaea grayi (Archaeidae), showing the "neck" and long chelicerae (bar = 1 mm)
Zearchaea clypeata (Mecysmaucheniidae), showing the less long "neck" and chelicerae
Boagrius sp. (Palpimanidae), showing the enlarged front legs (bar = 1 mm)
The Araneomorphae are an infraorder of spiders. They are distinguishable by chelicerae (fangs) that point diagonally forward and cross in a pinching action, in contrast to the Mygalomorphae, where they point straight down. Araneomorphs comprise the vast majority of living spiders.
Araneomorphae
This Atrax robustus shows the orientation of Myglamorphae fangs.
This Cheiracanthium punctorium shows the orientation of Araneomorphae fangs.