Turcinoemacheilus, Banarescu & Nalbant, 1964

Turcinoemacheilus View in CoL

Turcinoemacheilus are small fishes that can be readily distinguished from all other nemacheilids in West Asia by their very slender body and the position of the anus, which is notably situated in front of the anal origin. Before 2013, only one species was known in the genus, but subsequent research revealed 11 species. Turcinoemacheilus are commonly found in the headwater streams and small rivers of the Euphrates, Tigris, and Zayandeh drainage, an endorheic basin in Iran. One species was described from the Himalayas, suggesting a much wider distribution range for the genus. Several small South Asian loaches exhibit superficial similarities to Turcinoemacheilus , and their phylogenetic relationships require further investigation. Turcinoemacheilus may represent a relatively common genus in the Himalayas, or these fishes may belong to different genera.

Further reading. Conway et al. 2011 ( T. himalaya ); Esmaeili et al. 2014c (revision); Jouladeh-Roudbar et al. 2023c (revision Iran, phylogeny).

Key to species of Turcinoemacheilus in West Asia

1a - Anus situated behind middle between pelvic and anal origins. ………………….2

1b - Anus situated at middle or in front of middle between pelvic and anal origins. ………………….5

2a - Lateral line complete, reaching to anterior part of caudal. …………………. T. christofferi

2b - Lateral line incomplete, reaching to midway between tip of pectoral and dorsal origin or midway between dorsal and anal origins. ………………….3

3a - Usually an elongated, irregularly shaped dark- brown blotch on side of anal base. …………………. T. bahaii

3b - No dark blotch-brown on side of anal base. ………………….4

4a - Body depth at dorsal origin 10–13 % SL. …………………. T. ansari

4b - Body depth at dorsal origin 13–15 % SL. …………………. T. hafezi

5a - No dark-brown stripe along lateral midline; 7–9 distinct dark-brown blotches on flank not forming a row. …………………. T. saadii

5b - Prominent row of dark-brown blotches along lateral midline, usually fused into a stripe. ………………….6

6a - Caudal–peduncle length 6–7 % SL; 4–5 mandibular pores. …………………. T. minimus

6b - Caudal–peduncle length 7–10 % SL; 5–7 mandibular pores. ………………….7

7a - Midlateral stripe narrower than eye diameter; prepelvic distance 47–50 % SL. …………………. T. kosswigi

7b - Midlateral stripe broader than eye diameter; prepelvic distance 50–55 % SL. ………………….8

8a - A dark-brown blotch at anal base. …………………. T. moghbeli

8b - No dark-brown blotch at anal base. ………………….9

9a - Interorbital distance 31–37 % HL. …………………. T. inexpectatus

9b - Interorbital distance 23–31 % HL. …………………. T. ekmekciae Turcinoemacheilus ansari

Common name. Beshar dwarf loach.

Diagnosis. Distinguished from other species of Turcinoemacheilus in West Asia by: body depth 10–13 % SL / ○ no dark-brown blotch on side of anal base / ○ anus situated behind middle between pelvic and anal origins / ○ mottled colour pattern or a prominent irregular-shaped dark-brown stripe along lateral midline disconnected from dark-brown blotches on back. Size up to 50 mm SL.

Distribution View Figure . Iran: Merian, Beshar, and Khersan in upper Karun drainage.

Habitat. Fast-flowing sections of small rivers and streams, usually in rapids and riffles with coarse gravel or rocks. Inhabits interspaces in gravel.

Biology. No data.

Conservation status. EN; restricted to a small area where it is in decline.

Remarks. Syntopic with T. saadii in Beshar.

Further reading. Jouladeh-Roudbar et al. 2023c (description).