Robustichthys

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Robustichthys
Temporal range: Anisian
Robustichthys.jpg
Fossil specimens, (A) IVPP V18568 (holotype), (B) IVPP V20416
Robustichthys 1.jpg
Reconstruction
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Clade: Halecomorphi
Order: Ionoscopiformes
Genus: Robustichthys
Xu et al., 2014
Type species
†Robustichthys luopingensis
Xu et al., 2014

Robustichthys is an extinct genus of ray-finned fish from the Middle Triassic period, contains only one species R. luopingensis. [1] [2] It belonged to the clade Halecomorphi, which were once diverse during the Mesozoic Era, but which are today represented by only a single species, the bowfin. Halecomorphs are holosteans, a clade which first appeared in the fossil record during the Triassic. [3]

Description

Robustichthys is described from Anisian Guanling Formation, Luoping, Yunnan, China. It is the oldest member of Ionoscopiformes, an order within Halecomorphi. [1] The largest specimen reaches length about 36 cm (1.18 ft), which makes it the largest holostean fish in the Middle Triassic. [2]

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References

  1. 1 2 Xu, Guang-Hui; Zhao, Li-Jun; Coates, Michael I. (May 2014). "The oldest ionoscopiform from China sheds new light on the early evolution of halecomorph fishes". Biology Letters. 10 (5): 20140204. doi:10.1098/rsbl.2014.0204. ISSN   1744-9561. PMC   4046378 . PMID   24872460.
  2. 1 2 Xu, Guang-Hui (2019-06-24). "Osteology and phylogeny of Robustichthys luopingensis, the largest holostean fish in the Middle Triassic". PeerJ. 7: e7184. doi: 10.7717/peerj.7184 . ISSN   2167-8359. PMC   6596411 . PMID   31275762.
  3. López-Arbarello, Adriana; Sferco, Emilia (March 2018). "Neopterygian phylogeny: the merger assay". Royal Society Open Science. 5 (3): 172337. Bibcode:2018RSOS....572337L. doi: 10.1098/rsos.172337 . PMC   5882744 . PMID   29657820.