Oxynoemacheilus kaynaki

Freyhof, Jörg, Kaya, Cüneyt, Turan, Davut & Geiger, Matthias, 2019, Review of the Oxynoemacheilus tigris group with the description of two new species from the Euphrates drainage (Teleostei: Nemacheilidae), Zootaxa 4612 (1), pp. 29-57 : 39-42

Oxynoemacheilus kaynaki Erk‘akan, Özeren & Nalbant, 2008

( Fig. 7–9 )

Oxynoemacheilus kaynaki Erk‘akan, Özeren & Nalbant, 2008:115, figs. 1–3 (type locality: Turkey: Göksu River, Nurhak, Elbi- stan, Firat basin, 37°53‘22.82‘‘N 37°22‘19.99‘‘E).

Material examined. FFR 1447, 7, 60–64 mm SL; FFR 15519, 15, 46–65 mm SL; Turkey: Malatya prov.: stream Sultan Suyu, about 8 km east of Akçadağ, 38.339 38.062.— FFR 1466, 13, 31–61 mm SL; Turkey: Sivas prov.: stream Kangal, about 2 km east of Çetinkaya , 39.253 37.626 .— FFR 1483, 3, 31–42 mm SL; Turkey: Sivas prov.: stream Kangal, about 4 km east of Çetinkaya , 39.278 37.653 .— FFR 15509, 14, 52–68 mm SL; Turkey: Adıyaman prov.: stream Göksu at Düzbağ , 37.795 37.471 .— FFR 15528, 20, 35–63 mm SL; Turkey: Muş prov.: stream Kay- narca at Tepe , 39.107 41.492.— FSJF 1989 , 11 , 31–48 mm SL; Turkey: Elazığ prov.: stream Gül at Karakocan, at road from Elazığ to Bingöl, 38.9660 40.0271.— FSJF 2937 , 2 , 67–68 mm SL; Turkey: stream Sürgü between Hamzalar and Kapıdere , 37.9536 37.6952.— FSJF 2911 , 26 , 29–64 mm SL; Turkey: Sivas prov.: stream Kangal under railway bridge at Çetinkaya 39.2516 37.6189. IUSHM 2019-1412 , 2 , 52–54 mm SL; Turkey: stream Tatlı at Kabakçevliği, 25 km east of Kangal , 39.3013 37.6743 .

Material used in molecular genetic analysis. FFR DNA- 297–299, 318, 319, 322, 323, 326, 327; Turkey: Adıyaman prov.:stream Göksu at Düzbağ , 37.705 37.479.(GenBank accession numbers: MK 546494 - MK 546496 ). — FFR DNA-265–267 ; Turkey: Malatya prov.: stream Sultan Suyu, about 8 km east of Akçadağ , 38.339 38.062. (GenBank accession numbers: MK 546490 - MK 546492 ).—FFR DNA-262 , 275 ; Turkey: Turkey: Sivas prov.: stream Kangal under railway bridge at Çetinkaya 39.2516 37.6189. (GenBank accession numbers: MK546489 , MK546493 ).—FFR DNA-335–336 ; Turkey: Muş prov.: stream Kaynarca at Tepe , 39.107 41.492. (GenBank ac- cession numbers: MK 546503 - MK 546504 )— FSJF DNA-1389 ; Turkey: Sivas prov.: stream Kangal under railway bridge at Çetinkaya 39.2516 37.6189. (GenBank accession numbers: MK 546473 - MK 546474 ).— FSJF DNA- 1473 ; Turkey: stream Sürgü between Hamzalar and Kapıdere, 37.9536 37.6952. (GenBank accession numbers: MK 546461 - MK 546462 ).— FSJF DNA-2401 ; Turkey: stream Tatlı at Kabakçevliği, 25 km east of Kangal , 39.3013 37.6743. (GenBank accession number: MK 546475 ) .

Additional distribution records. GBIF: 39.2516 37.6189, 37.9536 37.6952.

Diagnosis. Oxynoemacheilus kaynaki is distinguished from O. ercisianus and O. hazarensis by having a complete lateral line (vs. incomplete), a shallow, wide and long dorsal adipose ridge on the caudal peduncle not elevated from the dorsal profile on caudal peduncle, reaching to the middle of the caudal peduncle or below the last dorsalfin ray when folded down (vs. no dorsal-adipose crest or ridge in individuals smaller than 50 mm SL, if present, short, reaching forward to vertical through base of last anal-fin ray, but usually much shorter, elevated from dorsal profile), no suborbital groove in the male (vs. present in O. hazarensis ), the flank covered by scales (vs. absent in O. ercisianus , scales present on caudal peduncle in O. hazarensis ), and a bold, dark-brown or black bar at the caudal-fin base (vs. a mottled pattern).

Distribution. Oxynoemacheilus kaynaki was described from the upper Göksu River drainage and it is here re- ported from the stream Kaynarca and the stream Gül, which is a headwater of the Peri Suyu, the Sultan Suyu, which flows to the Karakaya reservoir and the Kangal stream, which flows to the Keban reservoir.

Remarks. Our molecular data ( Fig. 1 ) place O. kaynaki in the O. tigris species group.

Oxynoemacheilus kaynaki is widespread in the upper Euphrates drainage ( Fig. 2 ). Our data strongly suggest that there are many more or less isolated populations of O. kaynaki which also show little molecular and morphological differences. The intraspecific variability in O. kaynaki ranges from 0.5% K2P distance between the populations from the Kaynarca (Murat) and the Göksu River to 1.0% K2P distance between the Kangal and Sultan Suyu drainages.

Oxynoemacheilus kaynaki from the Kangal and Sultan Suyu are distinguished from those of the Göksu and Murat by having a shorter dorsal adipose ridge, reaching forward to the vertical through the base of the last anal-fin ray, but usually much shorter (vs. very long not elevated from the dorsal profile, reaching below the last dorsal-fin ray when folded down), 8–11 small brownish blotches on the back (vs. 5–8 large blackish blotches or saddles), and a deeper caudal peduncle (13–15% SL vs. 10–13). However, the grouping in fishes with a long or a short dorsal adipose ridge is not supported by molecular character and would make the two groups paraphyletic. Furthermore, we expect also more morphologically intermediate fishes, when more populations will be examined in the future. Therefore, all these populations are identified as O. kaynaki .

Erk‘akan et al. (2008) described O. kaynaki as having a convex or truncate caudal fin. They show a very poor quality photograph of the holotype, in which the upper and lower part of the caudal fin seems to be broken. In our material, there are several individuals which have an almost truncate caudal fin, but no individual has a convex caudal fin.

Oxynoemacheilus kaynaki is distinguished from O. araxensis , O. argyrogramma , O. bergianus , O. euphraticus , and O. samanticus by having no suborbital groove in the male (vs. present), a slightly emarginate or almost truncate caudal fin (vs. deeply emarginate or slightly forked), and no black spots at the caudal-fin base (vs. having two bold black spots in O. argyrogramma and O. euphraticus ).

Oxynoemacheilus kaynaki is distinguished from O. paucilepis by having a long dorsal adipose ridge on the caudal peduncle (vs. no ridge or crest), the flank with a mottled or marmorate brown pattern, with irregularly shaped brown bars, especially on the flank behind the dorsal-fin origin in some individuals (vs. flank with a distinct midlateral series of roundish or horizontally elongated large brown blotches and a row of small brown blotches between the upper pelvic-fin base and the lowermost caudal-fin base).

Figures

FIGURE 1. Maximum likelihood estimation of the phylogenetic relationships based on the mitochondrial COI barcode region (K2P model, discrete Gamma distribution for rate differences with 3 categories (+G, parameter = 0.2094)). Nucleotide positions with less than 95% site coverage were eliminated, resulting in 605 analysed positions. Numbers of major nodes indicate bootstrap values from 1000 pseudoreplicates from the ML, NJ and MP method. X denotes highest possible support from all three methods (>95). 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 out group. The tree is drawn to scale with branch lengths depicting number of substitutions per site.

FIGURE 2. Site scale records of species of the Oxynoemacheilus tigris species group based on material listed in this study.

FIGURE 7. Oxynoemacheilus kaynaki, from top: FFR 15509, 67 mm SL, 63 mm SL; 62 mm SL; Turkey: stream Göksu.

FIGURE 8. Oxynoemacheilus kaynaki, from top: FSJF 2937, 68 mm SL; Turkey: stream Sürgü; FFR 15528, 63 mm SL; Turkey: stream Kaynarca.

FIGURE 9. Oxynoemacheilus kaynaki, from top: FFR 15519, about 50 mm SL; Turkey: stream Sultan Suyu; IUSHM 2019- 1412, 54 mm SL; Turkey: stream Tatlı; FSJF 2911, 64 mm SL, Turkey: stream Kangal.