''Parapeytoia'' was a prehistoric arthropod that lived over 530 million years ago (

Cambrian Stage 3 Cambrian Stage 3 is the still unnamed third stage of the Cambrian. It succeeds Cambrian Stage 2 and precedes Cambrian Stage 4, although neither its base nor top have been formally defined. The plan is for its lower boundary to correspond approxi ...

) in the

Maotianshan shales The Maotianshan Shales are a series of Early Cambrian deposits in the Chiungchussu Formation, famous for their '' Konservat Lagerstätten'', deposits known for the exceptional preservation of fossilized organisms or traces. The Maotianshan Shales ...

of prehistoric China. It was interpreted as an

anomalocaridid Radiodonta is an extinct order of stem-group arthropods that was successful worldwide during the Cambrian period. They may be referred to as radiodonts, radiodontans, radiodontids, anomalocarids, or anomalocaridids, although the last two origi ...

(radiodont) with legs, but later studies reveal it was a

megacheira Megacheira ("great hands") is an extinct class of predatory arthropods that possessed a pair of great appendages, hence the class name as well as the common name "great appendage arthropods". Their taxonomic position is controversial, with stud ...

n, a group of arthropods which are no longer thought to be closely related to the radiodonts. 20191021 Parapeytoia yunnanensis interpretation

''Parapeytoia'' is known from a few incomplete

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...

materials with part of its ventral structures preserved. The frontmost

appendages An appendage (or outgrowth) is an external body part, or natural prolongation, that protrudes from an organism's body. In arthropods, an appendage refers to any of the homologous body parts that may extend from a body segment, including anten ...

were a pair of

great appendage Great appendages are claw-like appendages which attach to the heads of the "great appendage arthropods", a name usually refers to Megacheira, a class of extinct arthropod characterized by a pair of "short-great appendages" bearing in front of the ...

s that had a peduncle and 4 spines on each of them, a characteristic feature shared by other

ns such as ''

Yohoia ''Yohoia'' is an extinct genus of megacheiran arthropod from the Cambrian period that has been found as fossils in the Burgess Shale formation of British Columbia, Canada. It has been placed among the arachnomorpha, a group of arthropods that in ...

'' and '' Fortiforceps''. Behind the great appendages were 2 or 3 pairs of short appendages, and numerous pairs of well-developed biramous appendages, each formed by a basipod with spiny gnathobase, lobe-like exopod and leg-like endopod with 8 segments. A narrow sternite associated between each of those appendages. Some features originally interpreted as

-like are more or less questionable, such as radial sclerites interpreted as its mouthparts have since been assigned to another genus of animal, ''

Omnidens ''Omnidens amplus'', meaning "large all-tooth", is an extinct species of large Cambrian animal known only from a series of large mouth apparatus, originally mistaken as the mouthparts of anomalocaridids. When first named, it was interpreted as ...

''. ''Parapeytoia'' was in all likelihood a benthic feeder, spending most of its time on the ocean floor hunting (or possibly scavenging) for prey.

References

Dinocaridids: anomalous arthropods or arthropod-like worms? by Hou Xianguang & Jan Bergström 2006
arguing that this genus is a dinocaridid

External links

{{Taxonbar, from=Q2732162 Megacheira Cambrian arthropods Maotianshan shales fossils Prehistoric arthropod genera Cambrian genus extinctions