Leuciscus aspius (Linnaeus, 1758)

Freyhof, JÖrg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 348-350

Leuciscus aspius

Common name. Asp.

Diagnosis. Distinguished from L. vorax by: ● 61–73+3 lateral line scales / ● lower lip slightly projecting upper lip. Size up to 800 mm SL.

Distribution. Widespread in Caspian basin. Sakarya and rivers west of Sakarya. In Rioni drainage ( Georgia) but absent from Black Sea basin south of Danube. Large rivers

Recent records appear to be based on a misidentification of Rutilus lacustris , a non-native species in the Hari. The identity of L. latus requires further clarification, and the species has not been recorded in the 20 th or 21 st century. It cannot be excluded that L. latus is a synonym of one of the Central Asian Leuciscus species. Central Asian species, including L. baicalensis , L. bergi , L. lehmanni , L. lindbergi , L. squaliusculus , and L. dzungaricus , all share the same or highly similar mitochondrial DNA haplotypes ( COI). This species group requires taxonomic revision. Aspiolucius esocinus is an asp native to the Aral basin, which appears to be closely related to Leuciscus and may be transferred to that genus in the future. Further reading. Jouladeh-Roudbar et al. 2020 (misidentification of L. latus ).

draining into Aral Sea and North Sea (Weser, Elbe), Baltic Sea (southern tributaries, Norway east of Oslo, southern Sweden, Kokemären drainage in southern Finland), northern Black Sea, Sea of Azov and Caspian Sea; Aegean basin from Maritza to Lake Volvi drainages. Introduced in Rhine, Rhone, and other French rivers, Po ( Italy), northern Dvina (Russia), Lake Balkhash (Central Asia), and likely elsewhere.

Habitat. Open waters of large and medium-sized lowland rivers and large lakes. Often found in freshwater parts of sea. Spawns on gravel or submerged vegetation in fast-flowing water. Lake populations migrate into tributaries.

Biology. Lives more than 10 years. First spawns at 3–5 years. Reproductive success appears to be linked to low water levels and high spring temperatures. Spawns more than one season, in March–early April (mid–May in Volga), when temperatures rise above 8°C (Rhine) or even lower (4–6°C on Terek) in places with strong currents. Spawning takes about 2 weeks, often just few days. Eggs are attached to gravel or submerged vegetation. Semi-anadromous individuals or populations (Terek) forage mainly in estuaries and freshened parts of sea, migrating to rivers only to spawn. Begins spawning migration in second half of October (Terek) and overwinters in lower part of river. Juveniles gregarious predators; adults hunt in small groups or are solitary. Juveniles and adults feed mainly on fish, especially Atherina and Alburnus . Juveniles grow rapidly, reaching about 80–100 mm SL in first year. In Europe, often hybridises with Leuciscus idus .

Conservation status. LC. Seems to be extirpated from Sakarya.

Remarks. Records from Lake Manyas ( Türkiye) could not be confirmed. Populations from the southern Caspian and Aral basins are reported to have up to 90 total lateral line scales and often red lips. The morphology of asps has not been studied in detail, and molecular studies ( COI), including asps from the Aras, Aral basin, and Europe, show that all populations are very closely related and show no geographical structure.

Further reading. Baruš & Oliva 1995 (biology); Riehl et al. 2002 (reproduction); Kottelat & Freyhof 2007 (biology, distribution); Coad 2021a (biology, morphology).

Large reservoirs in Aras drainage, like this one (Karakurt reservoir), are occupied by Leuciscus aspius .

Leuciscus vorax ; fish market in Homs, Syria; ~ 300 mm SL.