Squalius lepidus, Heckel, 1843

Freyhof, JÖrg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 411-414

Squalius lepidus

Common name. Mesopotamian pike chub.

Diagnosis. Distinguished from S. berak and S. verepi in Persian Gulf basin by: ● lower lip projecting beyond upper lip or tip of both lips equal / ● posterior anal margin straight / ● 9–10½, rarely 8½ branched anal rays / ● 45–60+1–3 lateral-line scales / ● head pointed /

Remarks. Very rare in Seyhan.

Further reading. Turan et al. 2009a (description);Bayçelebi 2020 (distribution).

● snout long / ● dorsal head profile straight or concave / ● scale pockets on flank not or moderately covered by pigments forming a grey crescent-shaped blotch, resulting in a poorly contrasted reticulate pattern or reticulate pattern absent. Size up to 350 mm SL, likely to grow larger.

Squalius lepidus ; Tigris drainage, Iran; 187 mm SL.

Distribution. Euphrates, Tigris, and Karun drainages.

Habitat. Large- to medium-sized rivers, lakes, and reservoirs from where they migrate to tributaries to spawn. Rarely in small streams.

Biology. Spawns May–June.

Conservation status. LC.

Remarks. In medium-sized rivers, it often occurs in sympatry with S. berak (Euphrates) or S. verepi (Tigris) , which inhabits mostly small- to medium-sized streams. Sympatric species occasionally hybridise, as mitochondrial DNA from S. berak and S. verepi is often found in S. lepidus , and there are many populations similar to hybrids between these species (relatively long head). Many individuals “difficult to identify” by the characters may be such hybrids. Chubs identified as S. lepidus from Lake Beyşehir, Lake Akşehir, Ceyhan, and the Orontes belong to other species.

Further reading. Bogutskaya 1994 (description); Coad 2021a (biology, morphology).

Tigris at Diyarbakır is the habitat of Squalius lepidus and many other large-river species.

Hybrid between Squalius verepi and Alburnus sellal ; 170 mm SL; Tigris drainage, Türkiye.

Squalius spurius ; Aleppo, Syria (from Heckel 1843).

Leuciscus spurius , a lost mystery fish? Leuciscus spurius was first described by Heckel in 1843 from the Qweiq in Aleppo, a region where the fish fauna was largely unknown to scientists at the time. It was frequently listed as occurring in the area by authors who copied information from Heckel’s description. After 145 years of its description, L. spurius was recorded from coastal streams in Syria, but later these fish were described as Alburnus qalilus . The generic position of L. spurius was discussed on a few occasions, partly based on the sole individual from Heckel’s collection and the accompanying illustration in the original description. Indeed, this species was never found again. A thorough examination of the type specimen in the fish collection of the Natural History Museum in Vienna revealed that the type of L. spurius is indistinguishable from the hybrids between Squalius berak and Alburnus sellal , which are often found in the Euphrates. Both parental species also occur in the Qweiq, so they are expected to hybridise there. Such hybrids exhibit a distinct phenotype that differs from their parental species. Consequently, Heckel described this individual as a different species. Further reading. Heckel 1843 (description); Krupp 1985d (records from Syria); Bogutskaya 1994; 1997b (discussion); Turan et al. 2009a (placement in Squalius ).

Squalius namak ; Nam, Western Kavir basin, Iran; ~ 280 mm SL.