Pauloterminus

<i>Pauloterminus</i>

Pauloterminus

Extinct shrimp-like stem group crustacean


Pauloterminus is an extinct genus of bivalved arthropod known from Early Cambrian (about 520 to 516 million years ago) Sirius Passet locality of northern Greenland. It is tentatively classified under the family Waptiidae.[1]

Quick Facts Scientific classification, Binomial name ...

The genus only has a single species P. spinodorsalis. It was first described by the paleontologist Rod S. Taylor in 2002. Its generic name is derived from Latin paulus ("small") and terminus ("end"). The specific name is from Latin spina ("thorn") and dorsalis ("of the back").[1]

Description

The ovoid-shaped bivalved carapace encloses the head and the anterior section of the trunk. The carapace is slightly less than twice as long as it is tall, and becomes wider posteriorly. The largest known carapace is 49.5 millimetres (1.95 in) long and 30 millimetres (1.2 in) wide, while in the smallest known specimens it is less than a centimere in length. The head is poorly known, though it is suggested that they lacked eyes. One specimen has partially preserved pair of segmented antennae, which have at least 4 segments, which decrease in length towards the end of the antenna. The thorax was likely tube shaped, and had six segments, each associated with a pair of biramous limbs, which decrease in size posteriorly. The limb endopods are thin and annulate, and approximately 1mm in width, while the exopods were lobe-shaped and bore setae. The abdomen was limbless and had five segments, and terminated in a pair of segmented caudal flukes.[1]

Taxonomy

In its original description, Pauloterminus was noted to be morphologically similar to Waptia and Chuandianella, both historically considered "waptiids", but it is unclear whether the group is monophyletic.[1]


References

  1. Rod S. Taylor (2002). "A new bivalved arthropod from the Early Cambrian Sirius Passet fauna, North Greenland". Palaeontology. 45 (Part 1). The Palaeontological Association: 97–123. doi:10.1111/1475-4983.00229.



Share this article:

This article uses material from the Wikipedia article Pauloterminus, and is written by contributors. Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.