Luciobarbus schejch, Heckel, 1843

Luciobarbus schejch View in CoL

Common name. Gattan.

Diagnosis. Distinguished from other species of Luciobar- bus in Persian Gulf basin by: ● back and upper flank yel- lowish or brown, lower flank yellowish or cream white in life, blackish or grey in large individuals / ○ head not strongly pointed, not depressed, barbel-like / ○ dorsal head profile convex / ○ mouth inferior or subterminal in very large individuals / ○ snout length 1.1–1.9 times in postor- bital length / ○ 50–62 total lateral-line scales / ○ 11–24 gill rakers / ○ lips fleshy, usually with median pad, lips hyper- trophied in some individuals / ○ juveniles without small dark-brown spots on upper flank. Size up to 800 mm SL and 30 kg (such large individuals might be hybrids with L. esocinus ).

Distribution. Euphrates, Tigris, Karun drainages, and coastal rivers of Persian Gulf south to Kol.

Habitat. Large streams, mountain and lowland rivers, lakes, reservoirs, and marshes, from which it migrates into tributaries to spawn. Spawns on gravel substrate in shallow areas of large rivers in 30−150 cm water depths.

Biology. Lives up to 11 years, probably longer. Maturity of males at 3 years and about 330 mm SL, females at 6 years and about 600 mm SL. Spawns June–August (Mosul), at dusk until just before midnight, with loud splashing, jumping, and chasing. Exclaims large areas of gravel to spawn in “nests.” Spawns once a year. Tolerant of low oxygen and moderate salinity. Feeds on a wide variety of aquatic inver- tebrates, small fish, detritus, and plants. Locally, molluscs are an important prey item.

Conservation status. LC; extirpated from Qweiq. Estab- lishes large populations in reservoirs. Highly overexploited in large rivers.

Remarks. Many, but not all, individuals of L. schejch carry mitochondria from L. esocinus , as hybridisation between the two species is common. Usually, male L. schejch spawns with female L. esocinus . Luciobarbus schejch with mito- chondria of L. schejch (not L. esocinus ) have been identified as L. kersin . Luciobarbus schejch with its own mitochondria and those with mitochondria of L. escocinus are widespread, occur in sympatry, and are indistinguishable by morphological characters. Luciobarbus kersin is a synonym of L. schejch . Luciobarbus schejch is often known as L. barbulus or, in parts of its range, as L. mystaceus . Luciobarbus barbulus is a junior synonym of L. schejch . Luciobarbus mystaceus has been described from the Kura in Georgia, and this species is a synonym of L. capito . Barbus rajanorum, described from Aleppo, is a hybrid of L. schejch and Capoeta damascina .

Further reading. Khaefi et al. 2017b (as L. barbulus ); Coad 2010a (biology, distribution as L. pectoralis , L. barbulus , and L. xanthopterus ); Coad 2021a (biology, mor- phology, as L. barbulus ); Freyhof et al. 2025a (taxonomic revision).