Glyptothorax cous (Linnaeus, 1766)

Freyhof, Jörg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 607

Glyptothorax cous

Common name. Mesopotamian torrent catfish.

Diagnosis. Distinguished from other species of Glyptothorax in West Asia by: ● thoracic adhesive apparatus 0.8–1.1 times longer than wide, poorly delineated at its posterior margin, only partly situated on shallow, horse-shoe shaped elevation; elevation absent in many adult individuals / ● striae reaching far beyond elevated apparatus, usually onto pectoral base, usually extending from isthmus to base of last pectoral ray or to posterior limit of pectoral base / ○ dorsal head, back and flank usually with large, bony, striated and elongated tubercles (absent in some individuals) / ○ adipose short, its length 0.6–1.2 times larger than distance between base of last dorsal ray and adipose origin / ○ anteromedial striae well developed / ○ medial pit open, without striae / ○ flank with large dark-brown blotches and or small dark-brown spots. Size up to 450 mm SL.

Distribution . Qweiq, Euphrates, Tigris and Karun drainages.

Habitat. Fast to moderately fast-flowing medium to large rivers.

Biology. Nocturnal, hiding under rocks during day. Feeds on benthic invertebrates, as adults, mainly on fish.

Conservation status. LC; extirpated from Qweiq.

Remarks. The mtDNA of G. cous from the Tigris is nested within mtDNA of G. daemon . There may have been some introgressive hybridisation between the two species. This would also mean that the mtDNA of G. cous from the Euphrates could be very different from that of Tigris population, and great caution should be exercised in identifying G. cous based on mtDNA alone.

Further reading. Russell 1756 (description); Freyhof et al. 2021c (description).

Figures

Glyptothorax cous

Distribution