Leuciscus kurui Bogutskaya, 1995

Freyhof, Jörg, Kaya, Cüneyt, Bayçelebi, Esra, Geiger, Matthias & Turan, Davut, 2018, Generic assignment of Leuciscus kurui Bogutskaya from the upper Tigris drainage, and a replacement name for Alburnus kurui Mangit & Yerli (Teleostei: Leuciscidae), Zootaxa 4410 (1), pp. 113-135 : 115-121

Leuciscus kurui Bogutskaya, 1995 , a valid species in Alburnus

Fig. 3–4

Material examined. FFR 04662, 3, 44– 46 mm SL; FSJF 3675 , 3 , 49–69 mm SL; Turkey: Hakkari prov.: spring at margin of Yüksekova wetland about 2 km west of Yürekli , 37.435, 44.366 .— FFR 04660, 2, 66– 74 mm SL; Turkey: Hakkari prov.: stream flowing to Yüksekova wetland about 500 m west of Yürekli, 37.431, 44.390.— ZMH 7361 , 83 mm SL, holotype; ZMH 8413 , 3 , 79–86 mm SL, paratypes; Turkey: Hakkari prov.: Yüksekova suyu in upper Tigris (Dicle Nehri) drainage east of Hakkari. M. Kuru, 17 Jun 1974 .

Material used in molecular genetic analysis. FSJF DNA-2668 , Turkey: Hakkari prov.: spring at margin of Yüksekova wetland about 2 km west of Yürekli , 37.435, 44.366 (GenBank accession number: MG 775332 – MG 775336 ) .

Diagnosis. Alburnus kurui is distinguished from A. timarensis by having less gill rakers on the first gill arch (8–12 vs. 13–17). The ventral keel between the end of the pelvic-fin base and the anus is absent in A. kurui and the mid-ventral line between the posterior part of the pelvic-fin base and the anus is completely covered by scales. In A. timarensis the ventral keel is present and scaleless for 5–10 scales in front of the anus (scales are counted beside the keel). Interestingly, in living A. kurui , there is an unpigmented line at the position where the ventral keel in other Alburnus species is situated. In A. kurui , the body is short and stout and the snout is rounded ( Fig. 3–4 ). In A. timarensis , the body is slender and elongated ( Fig. 5 ) and the snout is slightly pointed. In addition to the differences given above, A. kurui has a wider and deeper head (head width at nape 15–17% SL vs. 12–14; head depth at nape 18–20% SL, vs. 16–18). Alburnus kurui is distinguished from our materials of A. timarensis examined by having less total scales in the lateral series (51–58). Alburnus kurui is distinguished from A. sellal , A. heckeli and A. tarichi by having less gill rakers on the first gill arch (8–12 vs. 10–17 in A. sellal , 15–33 in A. heckeli , 18–27 in A. tarichi ), less total scales in the lateral series (51–58 vs. 66–89 in A. sellal , 77–93 in A. heckeli , 70–93 in A. tarichi ) and the absence of a ventral keep (vs. presence).

Distribution and habitat. Alburnus kurui is known only from the Yüksekova wetland in Turkey. The wetland is seasonally flooded, forming a large, shallow lake; in spring 2017, when the lake was dry, A. kurui was found only in a stream and a spring flowing to the wetland. Yüksekova wetland, though as yet unprotected, is a prime conservation site; with Yüksekova city being at an elevation of 1950 m a.s.l., this is the highest wetland in Turkey ( Yilmaz & Demircioglu Yildiz 2005).

Remarks. In its habitat, the fish were resting in small flocks directly under the water surface, a behaviour known from many other Alburnus species. Further, its general appearance let us speculate, immediately after we caught the fish, that it might be a member of the genus Alburnus . It is close to A. timarensis not only in its DNA barcode sequence but also in meristic characters ( Table 2 ). Therefore, we have no doubt that it is placed correctly in Alburnus , although we were able only to study DNA barcode data and no additional molecular characters.

The DNA barcode data place A. kurui in a cluster with specimens of A. timarensis from the Lake Van basin. While we found morphometric ( Table 1 ) and meristic ( Table 2 ) characters differentiating A. kurui from A. timarensis , both species are very similar in having low scale counts and gill-raker numbers ( Table 2 ). We found no A. timarensis with less than 64 total lateral line scales (64–75, n=20) and Elp et al. (2013) found no A. timarensis with less than 57 total lateral line scales (57–68, n=25). Kuru (1980) reported 8, 3 and 2 individuals with 54, 55 and 56 scales respectively (54–68, n=102). Danulat & Selcuk (1992) gave a range of 55–92 total lateral line scales (n=20) for A. tarichi and Ladiges (1960) and Berg (1949) reported for A. tarichi 53–94 and 65–82 total lateral line scales, respectively. Already Elp et al. (2013) suspect that their samples contained A. tarichi as well as A. timarensis . These studies let us speculate, that A. timarensis regularly has more than 57 lateral line scales and scale counts rarely overlap with those of A. kurui .

A. kurui 12 A. timarensis 153 A. sellal 74 8 7 4 6 4 3 2 2 2 2 2 A. selcuklui 20 3 3 1 1 1 A. heckeli 50 1 3 2 6 4 2 4 7 4 6 5 2 4 1 A. tarichi 148 15 8 24 12 9 13 6 5 2 4 2 1 2 1 A. caeruleus 30 continued. Scales above lateral line Scales below lateral line N 8 9 10 11 12 13 14 15 16 4 5 6 7 8

continued.

Figures

FIGURE 3. Alburnus kurui, from the top, a, FSJF 3675, 69 mm SL; b, FFR 04660, 66 mm SL; c, FFR 04660, 74 mm SL, Turkey: Yüksekova wetland.

FIGURE 4. Alburnus kurui, ZMH 7361, 83 mm SL, holotype; Turkey: Yüksekova suyu.

FIGURE 5. Alburnus timarensis, not preserved, about 120 mm SL; Turkey: stream Karasu 5 km east of Alaköy. Photo M. Özuluğ.