Jaekelocarpus

Jaekelocarpus Temporal range: Pennsylvanian (Morrowan),
Three-dimensional reconstruction of Jaekelocarpus oklahomensis (UWBM74305) with internal bars and bar-like structures (violet)
Scientific classification
Kingdom:	Animalia
Phylum:	Echinodermata
Class:	†Stylophora
Order:	†Mitrata
Family:	†Jaekelocarpidae
Genus:	†JaekelocarpusKolata et al., 1991
Species:	†J. oklahomensis
Binomial name
†Jaekelocarpus oklahomensis Kolata et al., 1991

Jaekelocarpus is a genus of mitratestylophoran known from the Morrowan age of the Golf Course Formation, southern Oklahoma, US.^[1] It possessed two billaterally symmetrical complexes of four internal bars. The morphological similarity of these structures to the gill bars of cephalochordates and enteropneusts is considered a likely indicator of their homology.^[2][3]

References

1. Kolata, Dennis R.; Frest, Terrence J.; Mapes, Royal H. (September 1991). "The youngest carpoid: occurrence, affinities, and life mode of a Pennsylvanian (Morrowan) mitrate from Oklahoma". Journal of Paleontology. 65 (5): 844–855. Bibcode:1991JPal...65..844K. doi:10.1017/S0022336000037811. ISSN 0022-3360.
2. Dominguez, Patrício; Jacobson, Antone G.; Jefferies, Richard P. S. (2002-06-20). "Paired gill slits in a fossil with a calcite skeleton". Nature. 417 (6891): 841–844. Bibcode:2002Natur.417..841D. doi:10.1038/nature00805. ISSN 1476-4687. PMID 12075349.
3. Álvarez-Armada, Nidia; Cameron, Christopher B.; Bauer, Jennifer E.; Rahman, Imran A. (2022-05-11). "Heterochrony and parallel evolution of echinoderm, hemichordate and cephalochordate internal bars". Proceedings of the Royal Society B: Biological Sciences. 289 (1974). doi:10.1098/rspb.2022.0258. ISSN 0962-8452. PMC 9091856. PMID 35538784.