Clarias gariepinus

Freyhof, JÖrg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 593

Clarias gariepinus

Common name. Sharptooth catfish.

Diagnosis. Distinguished from Clarias sp. in West Asia by: ● body slender, eel-like / ● body depth slightly increasing to dorsal origin, then decreasing / ● anterior margin of pectoral spine serrated / ● posterior dorsal tip not reaching to caudal base / ● flank brown or grey with dark-brown mottling. Size up to 1500 mm SL and 60 kg, usually about 700 mm SL.

Distribution. Native to Jordan drainage and coastal streams of Israel. Introduced in Azraq oasis, Orontes drainage in Syria and Türkiye. Widespread in southern Türkiye from Orontes to Göksu, probably elsewhere along Mediterranean coast. Also, in warm springs in Sakarya, Lake Burdur basin ( Türkiye), Al-Kharj south of Riyadh, and Medina ( Saudi Arabia). Probably found elsewhere. Nearly pan-African range, absent only from North Africa except Algeria, where it occurs in streams in Tolga oasis on northern edge of Sahara and gueltas on north slopes of Tassili n’ Ajjer. Tibesti and Ennedi massifs of Chad. Widespread in Nile and Niger drainages, eastern and southern Africa, but absent from upper and lower Guinea, Cape prov. and probably Nogal prov. of South Africa. Introduced in other parts of Africa, tropical and subtropical Asia, and South America. Occasional escapes from warm water aquaculture facilities in Europe are not established in natural waters but only in artificially heated waters.

Habitat. Slow-flowing or standing waters of lakes, marshes, reservoirs, and lowland rivers, rarely in fast-flowing waters. Often found in canals with both sewage and treated water. Tolerant of extreme environmental conditions, including temperatures as low as 8°C and very low oxygen conditions.

Clarias gariepinus, Lake Burdur basin, Türkiye, ~ 250 mm SL.

Biology. Lives up to 8 years. Matures at about 300–350 mm SL (males), 350–400 mm SL (females). An accessory respiratory organ allows this species to breathe air. Often found in muddy bottoms of dry ponds, occasionally swallowing air through mouth. Dependent on atmospheric oxygen and will drown if cut off from surface. Can leave water using its strong pectoral spines and move to new areas through very shallow channels. Spawning is usually triggered by rising water levels and flooding shallow areas. Spawns throughout year when water temperatures are above 22°C. Migrates to rivers and temporary streams to spawn. Spawns usually at night in shallow, flooded areas. Courtship often preceded by highly aggressive encounters between males. Generates monophasic, head-positive electrical discharges of 5–260 microSiemens during intra-specific aggressive interactions. Mating position, a form of amplexus, is maintained for several seconds. In amplexus, male lies in a U-shaped curve around female’s head. Sperm and eggs are released, followed by a vigorous female tail swish to spread eggs over a wide area. Pairs mate several times during a spawning night. Parents do not guard eggs or larvae. Eggs adhere to vegetation. Larvae usually begin feeding 48–72 hours after hatching (23–28°C). Nocturnal bottom feeders on invertebrates and fish, occasionally taking young birds, rotting flesh, and plants. An important commercial species in Africa. An important aquaculture species in warm-water and tropical countries, introduced almost worldwide.

Conservation status. LC.

Further reading. Teugels 1986 (distribution); Bruton 1979 (biology).