Hypopygus
Genus of fishes
From Wikipedia, the free encyclopedia
Hypopygus is a genus of South American gymnotiform knifefishes native to the Amazon, Orinoco and upper Paraguay basins, as well as rivers in the Guianas.[2][3] They are often common, and found near submerged roots, aquatic vegetation and leaf-litter in streams, edges of rivers and floodplains.[2] They are regularly found among vegetation in floating meadows, a habitat that often contains little oxygen, but they are well-adapted to this.[4]
| Hypopygus | |
|---|---|
Scientific classification  | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Gymnotiformes |
| Family: | Rhamphichthyidae |
| Genus: | Hypopygus Hoedeman, 1962[1] |
| Type species | |
| Hypopygus lepturus Hoedeman, 1962[1] | |
| Synonyms[1] | |
|
Stegostenopos Triques, 1997 | |
They are well-camouflaged and brown in color with a banded/mottled pattern.[2][3][5] They generally resemble the related Steatogenys, but are smaller,[6] reaching up to 5.9–12.2 cm (2.3–4.8 in) in total length depending on the exact species of Hypopygus.[7] The smallest is H. hoedemani, which is the second-smallest knifefish,[2] after Microsternarchus brevis.[8] They are nocturnal and feed on small invertebrates. During the day they remain hidden, often in groups that may number several dozen individuals.[2]
Taxonomy and species
Hypopygus has traditionally been included in the family Hypopomidae,[9] but a comprehensive molecular study from 2015 showed it belongs in Rhamphichthyidae,[10] and this has been followed by recent authorities.[11][12]
Hypopygus contains the following species:[13]
- Hypopygus benoneae L. A. W. Peixoto, Dutra, de Santana & Wosiacki, 2013
- Hypopygus cryptogenes (Triques, 1997)
- Hypopygus hoedemani de Santana & Crampton, 2011 (Hoedeman's Hypopygus)
- Hypopygus isbruckeri de Santana & Crampton, 2011 (Isbrücker's Hypopygus)
- Hypopygus lepturus Hoedeman, 1962
- Hypopygus minissimus de Santana & Crampton, 2011
- Hypopygus neblinae Mago-Leccia, 1994
- Hypopygus nijsseni de Santana & Crampton, 2011 (Nijssen's Hypopygus)
- Hypopygus ortegai de Santana & Crampton, 2011 (Ortega's Hypopygus)
- Hypopygus varii Campos-da-Paz 2018
