Carasobarbus hajhosseini, new species

(Figs. 10, 11, 12 and 13).

Holotype. BIAUBM 7-H, 190.6 mm SL; Iran: Ilam prov. Seymareh River at Talkhab, Karkheh drainage, Persian Gulf basin, 33.27771, 47.21252 .

Paratypes. AJRPC 18-P, 4, 85.8–184.3 mm SL; same data as holotype. AJRPC 19-P, 2, 95.0– 108.9 mm SL; Iran: Lorestan prov. Kahman River at Doab, Karkheh drainage, Persian Gulf basin, 33.78557, 48.20640. AJRPC 20-P, 1, 117.5 mm SL; Iran: Lorestan prov. Karkheh River at Pa Alam, Karkheh drainage, Persian Gulf basin, 32.83141, 48.03337. AJRPC 21-P, 1, 136.9 mm SL; Iran: Lorestan prov. Karkheh River at Mamulan, Karkheh drainage, Persian Gulf basin, 33.37823, 47.95654. AJRPC 22-P, 1, 113.2 mm SL; Iran: Lorestan prov. Karkheh River at Kal Sefid, Karkheh drainage, Persian Gulf basin, 33.08346, 47.53871. AJRPC 23-P, 1, 93.7 mm SL; Iran: Ilam prov. Karkheh River at Pol Zaal, Karkheh drainage, Persian Gulf basin, 32.98729, 47.76504 .

New material used in molecular genetic analysis. AJRPC-DNA 225 (COI: PP 515178, Cyt b: PP 548212), Iran: Lorestan prov. Kahman River at Doab, Karkheh drainage, Persian Gulf basin, 33.78557, 48.20640; AJRPC-DNA 571A (COI: PP 515182, Cyt b: PP 548215), 571B (COI: PP 515183, Cyt b: PP 548216) same data as holotype.

Diagnosis

Carasobarbus hajhosseini sp. n. is distinguished from C. sublimus, C. saadatii sp. n. and C. doadrioi sp. n. by having more scales on lateral line (32–34 vs. 24–29 in C. sublimus; 40–44 in C. doadrioi sp. n.; 38–40 in C. saadatii sp. n.).

Carasobarbus hajhosseini sp. n. is similar to C. kosswigi but can be distinguished by slightly developed lower lip lobe (vs. well-developed), shorter head (20–24 vs. 24–27% SL), shorter posterior barbel (13–20 vs. 21–38% HL) and shorter snout (25–31 vs. 36–44% HL).

Also, the new species can be distinguished from C. luteus by having two pair of barbels (vs. one pair), well-developed median lobe on the lower lip (vs. without median lobe) and more scales on the lateral line (32–34 vs. 25–30).

Description

See Figs. 10, 11, 12 and 13 for general appearance, Table 6 for morphometric data. Body moderately high, laterally compressed, without nuchal hump. The greatest body depth at a level in front of or point of dorsal fin origin. Ventral head profile straight, dorsal profile has a slight to pronounced hump near nostrils. Head short and narrow. Maximum body depth larger than head length. Triangular axillary scale at pelvic-fin base. Pelvic-fin origin below vertical of last unbranched dorsal fin ray. Caudal fin forked. Tip of anal fin, when pressed to body, reaching to hypural complex. Pectoral fin reaching approximately 70–90% distance from pectoral-fin origin to pelvic-fin origin. Pelvic fin not reaching anus. Eye large, but smaller than snout. Mouth inferior, lips thick and fleshy with a small median lob. Two pairs of barbels, rostral not/or reaches to anterior part of eye and maxillary reaching to the posterior part of eye.

Dorsal fin with 4 unbranched rays and 10½ (n = 6)–11½ (n = 5) branched rays, outer margin deeply concave. Anal fin with 3 (n = 11) unbranched and 6½ (n = 11) branched rays, outer margin straight. Pectoral fin with 13 (n = 4), 14 (n = 6), 15 (n = 1) rays. Pelvic fin with 8 (n = 7)–9 (n = 4) rays. Lateral line with 32 (n = 3), 33 (n =4), 34 (n = 4) scales. Scale rows between dorsal-fin origin and lateral line 6 (n = 11). Scale rows between anal-fin origin and lateral line 5 (n = 11).

Coloration

In fresh: Body silverish or cream-white. The back darker than the belly. Upper lateral line scales outlined by dark pigmentation, evident in anterior and fade in posterior. Fins with scattered dark melanophores on rays and membranes. In formalin: Body cream-brown, back darker than belly. Upper lateral line scales outlined by dark pigmentation, prominent in anterior section, fades towards posterior.

Distribution

The new species is known from the Gamasiab, Kahman, Kashkan and Seymareh in Karkheh drainage.

Etymology

The species is named in honour of Haj Hossein Javadi Pour (HHJP), who is the father of the first author of this study (AJR).

Habitat

Carasobarbus hajhosseini is commonly found in the deep, swiftly flowing sections of rivers and dam reservoirs (Fig. 14). It typically favours areas with abundant vegetation, and during the summer, it can also be observed in shallower waters. Generally, the species is most abundant in the middle and lower Karkheh drainage. Luciobarbus esocinus, Capoeta shajariani Jouladeh-Roudbar, Eagderi, Murillo-Ramos, Ghanavi & Doadrio, 2017, Garra gymnothorax Berg, 1949, Chondrostoma regium, Alburnus sellal, Squalius lepidus Heckel, 1843, Squalius berak, Turcinoemacheilus saadii Esmaeili, Sayyadzadeh, Özuluğ, Geiger & Freyhof, 2014, Glyptothorax cous and G. alidaei were found coexisting with the new species.