Chondrostoma cyri, Kessler, 1877

Freyhof, JÖrg, Yoğurtçuoğlu, Baran, Jouladeh-Roudbar, Arash & Kaya, Cüneyt, 2025, Handbook of Freshwater Fishes of West Asia, De Gruyter : 335

Chondrostoma cyri

Common name. Southern Caspian nase.

Diagnosis. Distinguished from other species of Chondrostoma in Caspian, Persian Gulf, and Kor endorheic basins in Iran by: ● mouth strongly arched both in juveniles and adults / ● cornified sheath covering lower lip very thin / ○ 48–73, usually 52–62, total lateral-line scales / ○ 6–5, rarely 6–6 or 5–5, pharyngeal teeth / ○ 7−9½, usually 8½, branched dorsal rays / ○ 8−10½, usually 9½, branched anal rays / ○ (17) 21−26 (32) gill rakers. Size up to 246 mm SL.

Distribution. Caspian basin: Kura and Aras drainages.

Habitat. Foothill and mountain rivers with strong to slow currents, sandy, and rocky to gravelly bottoms, also in lakes and reservoirs. Spawns on hard bottoms, migrate from lakes and reservoirs into tributaries to spawn.

Biology. Lives at least 5 years and matures at 2–3 years. Spawning season depends on altitude and water temperature, peaking in April (lower Kura), June–July (upper Kura). Females spawn one batch of eggs per year. Feeds on periphyton.

Conservation status. VU; has declined due to hydropower development and pollution.

Further reading. Elanidze 1983 (morphology, biology); Elvira 1987 (review); Güçlü et al. 2018 (morphology); Çiftçi

et al. 2020 (phylogeny); Kaya et al. 2020a (distribution); Coad 2021a (biology, morphology).