Osteogaster

  1. Home
  2. Wiki

Osteogaster
Osteogaster eques
Scientific classification Edit this classification
Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Siluriformes
Family: Callichthyidae
Subfamily: Corydoradinae
Genus: Osteogaster
Cope, 1894
Type species
Corydoras eques
Steindachner, 1876
Species

See text

Osteogaster is a genus of catfish in the subfamily Corydoradinae, family Callichthyidae of the order Siluriformes. Before the recent resurrection of the genus, these species have been grouped in the genus Corydoras.

Taxonomy

[edit]

Osteogaster was erected by Edward Drinker Cope in 1894. Before 2024, it was considered defunct by most scientific authorities, being considered as a junior synonym or subgenus of Corydoras.[1] It was formally resurrected and revalidated in a phylogenomic analysis carried out in 2024.[2]

Etymology

[edit]

The generic name, Osteogaster, is derived from the Greek ὀστέον ostéon meaning bone, and γαστήρ gastḗr meaning belly; referring to the coracoid bones of O. eques which completely enclose the ventral region.[3]

Morphology

[edit]
Osteogaster aenea
Osteogaster rabauti

The basic color of species of the genus Osteogaster is yellowish-orange to reddish-orange, and there is a single large dark spot on the sides of the body. The fins are usually unspotted. Osteogaster species differ from all other armoured catfishes in the following characteristics, among others:[2]

  1. The mesethmoid, a skull bone, is small to medium-sized. In Gastrodermus, the mesethmoid is noticeably short. In Corydoras, it is large, and in Brochis, it is very large.
  2. The posterior edge of the pectoral fin spine is usually provided with serrations, which are perpendicular or arranged at right angles to the spine. In Brochis, Corydoras, Gastrodermus, and Scleromystax, these serrations are directed toward the base of the pectoral fin spine.

Species

[edit]

As of September 2025, there are currently 8 extant species in this genus (as recognized by Eschmeyer's Catalog of Fishes),[4]

Incertae sedis

References

[edit]
  1. ^ Marcelo Ribeiro de Britto (January 2009) [Dec 2003]. "Phylogeny of the subfamily Corydoradinae Hoedeman, 1952 (Siluriformes: Callichthyidae), with a definition of its genera". Proceedings of the Academy of Natural Sciences of Philadelphia. 153: 119–154. doi:10.1635/0097-3157(2003)153[0119:POTSCH]2.0.CO;2 – via ResearchGate.
  2. ^ a b Angelica C Dias; Luiz F C Tencatt; Fabio F Roxo; Gabriel de Souza da Costa Silva; Sérgio A Santos; Marcelo R Britto; Martin I Taylor; Claudio Oliveira (March 2025). "Phylogenomic analyses in the complex Neotropical subfamily Corydoradinae (Siluriformes: Callichthyidae) with a new classification based on morphological and molecular data". Zoological Journal of the Linnean Society. 203 (3): zlae053. doi:10.1093/zoolinnean/zlae053.{{cite journal}}: CS1 maint: article number as page number (link)
  3. ^ Christopher Scharpf & Kenneth J. Lazara (12 September 2025). "Family CALLICHTHYIDAE Bonaparte 1835 (Armored Catfishes)". The ETYFish Project Fish Name Etymology Database. Christopher Scharpf and Kenneth J. Lazara. Retrieved 18 September 2025.
  4. ^ Eschmeyer, William N.; Fricke, Ron & van der Laan, Richard (eds.). "Species in the genus Osteogaster". Catalog of Fishes. California Academy of Sciences. Retrieved 19 September 2025.
  5. ^ Ohara, Willian Massaharu; Tencatt, Luis Fernando Caserta; Ribeiro de Britto, Marcelo (September 2016). "Wrapped in flames: Corydoras hephaestus, a new remarkably colored species from the Rio Madeira basin (Teleostei: Callichthyidae)". Zootaxa. 4170 (3): 539–552. doi:10.11646/zootaxa.4170.3.7. PMID 27701241. Retrieved 23 April 2024.