Tshekardocoleidae

Tshekardocoleidae
Temporal range: Cisuralian–Guadalupian
Fossil and life restoration of Moravocoleus permianus
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Coleoptera
Suborder: Protocoleoptera
Family: Tshekardocoleidae
Rohdendorf, 1944
Genera

See text

Synonyms[1]
  • Uralocoleidae G. Zalessky, 1947
  • Moravocoleidae Kukalová-Peck & Beutel, 2012

Tshekardocoleidae is an extinct family of stem group beetles, known from the Permian. They represent some of the earliest known beetles. They first appeared during the Cisuralian, before becoming extinct at the beginning of the Guadalupian.[2] A claimed Jurassic record is doubtful.[1] Like other primitive beetles, they are thought to have been xylophagous.[2] The oldest known beetle, Coleopsis, was originally assigned to this family, but is now assigned to its own family Coleopsidae.[1]

The Tshekardocoleidae are thought to have retained several plesiomorphies (ancestral characters) of Coleoptera in a broad sense. For instance, their elytra are flattened, lack epipleura (outer margins), cover the body loosely, and their tips extend beyond the apex of the abdomen. Their abdomens have a nearly cylindrical shape and are thought to have been flexible, apparently being able to strongly contract and expand. In extant beetles, the elytra are tight-fitting, forming a subelytral space which is absent in Tshekardocoleidae.[3]

Taxonomy

[edit]
undescribed Tshekardocoleid larvae, Tshekarda site

Kirejtshuk (2020) included the following genera in Tshekardocoleidae[1]

The genus Uralocoleus had been placed in the family by some authors, but the type species Uralocoleus splendens Zalessky 1947 was considered incertae sedis by Kirejtshuk (2020) as a possible beetle or cockroach. The second species placed in the genus "Uralocoleus" ultimus was rejected from placement in Uralocoleus and listed as "genus incertus" ultimus Ponomarenko, 2000.[1] The genus Dictyocoleus, described from the Jurassic and containing only the type species Dictyocoleus jurassicus Hong, 1982, was originally placed in the family but was excluded by Kirejtshuk (2020).[1]

References

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  1. ^ a b c d e f Kirejtshuk, Alexander G. (2020-02-17). "Taxonomic Review of Fossil Coleopterous Families (Insecta, Coleoptera). Suborder Archostemata: Superfamilies Coleopseoidea and Cupedoidea". Geosciences. 10 (2): 73. Bibcode:2020Geosc..10...73K. doi:10.3390/geosciences10020073. ISSN 2076-3263.
  2. ^ a b Zhao, Xianye; Yu, Yilun; Clapham, Matthew E; Yan, Evgeny; Chen, Jun; Jarzembowski, Edmund A; Zhao, Xiangdong; Wang, Bo (2021-11-08). Perry, George H; Fikacek, Martin (eds.). "Early evolution of beetles regulated by the end-Permian deforestation". eLife. 10: e72692. doi:10.7554/eLife.72692. ISSN 2050-084X. PMC 8585485. PMID 34747694.
  3. ^ Boudinot, Brendon Elias; Yan, Evgeny Viktorovich; Prokop, Jakub; Luo, Xiao-Zhu; Beutel, Rolf Georg (2022-07-28). "Permian parallelisms: Reanalysis of †Tshekardocoleidae sheds light on the earliest evolution of the Coleoptera". Systematic Entomology. 48: 69–96. doi:10.1111/syen.12562. ISSN 0307-6970. S2CID 251171914.