Cobitis turcica Hankó, 1924

Freyhof, Jörg, Bayçelebi, Esra & Geiger, Matthias, 2018, Review of the genus Cobitis in the Middle East, with the description of eight new species (Teleostei: Cobitidae), Zootaxa 4535 (1), pp. 1-75 : 38-41

Cobitis turcica Hankó, 1924

(Fig. 29)

Cobitis taenia turcica Hankó, 1924: 154 , pl. 3 fig. 8 (type locality: Turkey: Ereğli).

Cobitinula Anatoliae Hankó, 1924: 152 , pl. 3 fig. 6 (type locality: Turkey: Lake Ak-Göl (Ereğli).

Material examined. FSJF 1860 , 29 , 44–98 mm SL; Turkey: Aksaray prov.: stream Melendiz below canyon at road from Nevsehir to Ihlara , 38.326 34.241 .— FSJF 2481 , 3 , 44–85 mm SL; Turkey: Aksaray prov.: spring in Köşk Park within Sultanhanı , 38.241 33.545 .— FSJF 2528 , 22 , 50–79 mm SL; Turkey: Konya prov.: stream north of Sarı Yayla, draining to former Lake Samsam , 39.118 32.759 .— FSJF 2611 , 27 , 41–82 mm SL; Turkey: Aksaray prov.: stream Tuz at Gölyazı, at road from Eskil to Cihanbeyli , 38.552 33.200 .

Diagnosis. Cobiti s turcica is distinguished from other Cobitis species in the Mediterranean and the endorheic basins in Central Anatolia by usually having a flank pattern composed of many small blotches and spots not organised in the Gambetta zones (vs. organised in Gambetta zones in C. aliyeae , C. battalgilae , C. bilseli , C. erkakanae , C. evreni , C. levantina , C. simplicispina , C. sipahilerae and some individuals of C. phrygica , Z4 often dissociated into a wide band or field of small blotches and spots in C. battalgilae , C. dorademiri and C. phrygica ). In some individuals of C. turcica , there are rows of blotches along the flank probably homologous with the Gambetta zones Z2 and Z4. In these individuals of C. turcica , the blotches in Z4 are as large as the blotches in Z2 or even smaller (vs. blotches in Z4 much larger than in Z 2 in C. dorademiri , C. evreni , C. levantina , C. simplicispina and C. sipahilerae and most individuals of C. battalgilae and C. phrygica or a dark-brown stripe in Z4). In many individuals of C. turcica , the flank pattern is completely or partly absent (vs. always complete and present in all other Cobitis in the Middle East). Cobitis turcica is further distinguished from C. dorademiri by having a more narrow caudal peduncle (caudal-peduncle depth 0.6–0.8 times in caudal-peduncle length vs. 1.0– 1.2), from C. phrygica and C. simplicispina and by having a longer caudal peduncle (16–18% SL vs. 11–14 in C. phrygica , vs. 10–15 in C. simplicispina ), a shorter prepelvic distance in the male (54.0% SL vs. 56–60 in C. phrygica , vs. 56–57 in C. simplicispina ) and a shorter pectoral-fin length in the female (15–17% SL vs. 18–21 in C. phrygica ). Cobitis turcica and some individuals of C. phrygica are superficially very similar, but both species are clearly distinguished by a minimum of 6.2% K2P distance based on COI.

Cobitis turcica and C. battalgilae closely cluster together in the molecular analysis ( Fig. 1 ). Indeed, few individuals of C. battalgilae have the Gambetta zones dissociated into fine spots and blotches. In these individuals, the dissociated blotches in Z4 are organised in a wide band (vs. not organised in a band in C. turcica ). Male C. turcica are further distinguished from male C. battalgilae by having a more slender dorsal-fin depth (17–18% SL vs. 21–22), shorter caudal and pectoral fins (17–18% SL vs. 19–20 caudal-fin length; 15–17% SL vs. 19–20 pectoral-fin length) and C. battalgilae grows much larger, no female C. turcica was found to be larger than 98 mm SL (vs. female growing up to 135 mm SL in C. battalgilae ).

Cobitis turcica is distinguished from C. bilseli from Lake Beyşehir basin by having two laminae circularis in the male (vs. one) and it is further distinguished from C. evreni and C. levantina by having a pelvic axillary lobe or a very shallow pelvic axillary pad (vs. lacking).

Distribution. Cobitis turcica is found in the wider Lake Tuz basin where it is reported from Ereğli, Melendiz (Ihlara Valley), springs in Sultanhanı, and a stream north of Sarı Yayla and a stream at Gölyazı. Most likely it is more widespread in the area.

Remarks. Cobitis turcica and C. battalgilae closely cluster together in the resulting topology, but are distinguished by 1.2% K2P distance. However, both PTP approaches did not detect a species boundary between the two mitochondrial lineages in our phylogenetic reconstruction. The K2P distance of 1.2% indicates that both species are closely related and both could also be treated as one species. We accept populations with similar K2P distance as conspecific if we find no morphological differences (see chapters about C. fahireae and C. taenia and discussion below). But in contrast to these cases almost all individuals of C. turcica and C. battalgilae can be distinguished from each other and therefore qualify as two species.

Hanko (1924) described C. t. turcica and C. anatoliae in the same paper. As a First Reviser, Kottelat, (2012:29) gave precedence to C. turcica .

Molecular data ( Fig. 1 ) place C. turcica in the C. simplicispina species group ( C. battalgilae , C. bilseli , C. dorademiri , C. joergbohleni , C. phrygica , C. pirii , C. simplicispina , and C. sipahilerae ). See below for details to distinguish C. turcica from C. joergbohleni and C. pirii .

Figures

FIGURE 1. Maximum likelihood estimation of the phylogenetic relationships based on the mitochondrial COI barcode region (TN93 model, discrete Gamma distribution for rate differences with 3 categories +G parameter = 0.3792. Nucleotide positions with less than 95% site coverage were eliminated, resulting in 590 analysed positions. Numbers of major nodes indicate bootstrap values from 1000 pseudoreplicates from the ML, NJ and MP method. A star denotes highest possible support from all three methods. Solid bars right to the specimen labels indicate species delimitation results from PTP followed by the results of the mPTP approach as dashed bars. Except to the outgroups and the branch to the right part of the figure, the tree is drawn to scale with branch lengths depicting number of substitutions per site.