Chondrostoma ceyhanense

Common name. Cilician nase.

Diagnosis. Distinguished from other species of Chondrostoma in Central Anatolia and eastern Mediterranean basin by:○ 59−68 total lateral-line scales / ○ usually 6–6 pharyngeal teeth / ○ 8–9½ branched dorsal rays / ○ 9−11½, usually 9½, branched anal rays / ○ 24−29 gill rakers / ○ poorly cornified sheath covering lower lip / ○ back in front of dorsal without keel / ○ keel between anus and posterior pelvic base shallow but well-developed. Size up to 265 mm SL.

Distribution . Türkiye: Tarsus, Seyhan, and Ceyhan drainages.

Habitat. Moderate to fast-flowing large to medium-sized rivers with rocky or gravelly bottom. Common in reservoirs. Spawns in fast-flowing waters on shallow gravel beds, often in small tributaries.

Biology. Lives up to 5 years. First spawns at 2–3 years. Spawns April–June (Sır Reservoir, Ceyhan). Feeds on periphyton scraped from hard substrate.

Conservation status. LC.

Remarks. Chondrostoma ceyhanense, C. kinzelbachi, and C. toros are very closely related to C. regium and are difficult to distinguish. Future research may clarify whether they are better treated as distinct populations of C. regium .

Further reading. Kara & Solak 2004 (age, growth; as C. regium); Küçük et al. 2017 (description); Çiftçi et al. 2020 (phylogeny).