Helogenes

Helogenes
Helogenes marmoratus
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Actinopterygii
Order:	Siluriformes
Family:	Cetopsidae
Subfamily:	Helogeneinae Regan, 1911[2]
Genus:	Helogenes Günther, 1863[1]
Type species
Helogenes marmoratus Günther, 1863[1]
Synonyms[1]
Leyvaichthys Dahl, 1960

Helogenes, the driftwood marbled catfishes, is a genus of ray-finned fishes belonging to the family Cetopsidae, the whale catfishes.^[1] The fishes in this genus are found in tropical South America.

Helogeneinae is the sister taxon of Cetopsinae, the other subfamily in the family Cetopsidae.^[3]

Species

Helogenes contains the following valid species:^[4]

• Helogenes castaneus (Dahl, 1960)
• Helogenes gouldingi Vari & H. Ortega, 1986
• Helogenes marmoratus Günther, 1863
• Helogenes uruyensis Fernández-Yépez, 1967

Distribution

Helogenes species occur through much of the Amazon River basin, the southern portions of the Orinoco River basin, the coastal rivers of the Guianas, and at least the lower portions of the Tocantins River.^[5]

Description

In Helogenes, the dorsal fin base is short, the anal fin base is elongate, the dorsal and pectoral fins lack spines, the adipose fin is usually present, but is reduced or absent in one population of one species.^[6][5] Helogenes species grow to about 4.3–7.3 centimetres (1.7–2.9 in) SL.^[7]

Ecology

Helogenes species feed on allochthonous insects.^[3] The only species for which details of the ecology are known is H. marmoratus (refer to article for that species).

References

1. Fricke, Ron; Eschmeyer, William N. & van der Laan, Richard (eds.). "Genera in the family Helogeneinae". Catalog of Fishes. California Academy of Sciences. Retrieved 14 November 2025.
2. Richard van der Laan; William N. Eschmeyer & Ronald Fricke (2014). "Family-group names of recent fishes". Zootaxa. 3882 (2): 1–230. doi:10.11646/zootaxa.3882.1.1. PMID 25543675.
3. Vari, Richard P.; Ferraris, Carl J.; de Pinna, Mário C. C. (2005). "The Neotropical whale catfishes (Siluriformes: Cetopsidae: Cetopsinae), a revisionary study". Neotropical Ichthyology. 3 (2): 127–238. doi:10.1590/S1679-62252005000200001.
4. Fricke, Ron; Eschmeyer, William N. & van der Laan, Richard (eds.). "Species in the genus Helogenes". Catalog of Fishes. California Academy of Sciences. Retrieved 15 November 2025.
5. Ferraris Jr., Carl J.; Vari, Richard P. (2007-06-07). "Whale Catfishes Cetopsidae". Retrieved 2007-08-04.
6. Nelson, Joseph S. (2006). Fishes of the World. John Wiley & Sons, Inc. ISBN 0-471-25031-7.
7. Froese, Rainer; Pauly, Daniel (eds.). "Species in genus Helogenes". FishBase. December 2011 version.