THE LONG TRAIL: A CHIMERA-LIKE FOSSIL CRUSTACEAN INTERPRETED AS DECAPODA, STOMATOPODA, AMPHIPODA AND FINALLY ISOPODA

Authors

  • PAULA G. PAZINATO
  • CAROLIN HAUG
  • ROSEMARIE ROHN
  • KAREN ADAMI-RODRIGUES
  • RENATO PIRANI GHILARDI
  • MAX CARDOSO LANGER
  • JOACHIM T. HAUG

DOI:

https://doi.org/10.13130/2039-4942/15699

Keywords:

Peracarida; Isopoda; Permian; Paraná Basin; morphometric analysis; convergent evolution.

Abstract

The process of interpreting and evaluating a fossil is a difficult task. Isopoda is a species rich group of peracarid eumalacostracans which represent quite a challenge when found as fossils, independent of whether we are working with fragmentary or more complete specimens. Here we describe a new fossil species of crustacean, Platuropodus odysseus n. gen. n. sp., from the Irati Formation, Permian of Paraná Basin, Brazil. After misinterpretations, the fossil taxon is recognised here as a representative of Isopoda. The new species presents characters found in Phreatoicidea, Asellota and Oniscidea in a unique combination for the fossil and extant record, such as two pairs of sub-chelate anterior trunk appendages, a short region after the anus and flat uropods. This chimera-like morphology and a morphometric analysis of the sub-chelae indicate convergent evolution in the early diversification of Isopoda. The morphological diversification present in the Palaeozoic and Mesozoic fossil record of Eumalacostraca indicate a “push of the past” effect in different ingroups of Peracarida.

Downloads

Published

2021-06-03

Issue

Section

Articles