Oxynoemacheilus hazarensis Freyhof & Özuluğ, 2017

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: 37

publication ID

https://doi.org/10.11646/zootaxa.4612.1.2

publication LSID

lsid:zoobank.org:pub:FE1913E9-E308-4807-A706-1D0F7A7C674B

persistent identifier

http://treatment.plazi.org/id/7E5087BF-6D7A-FFA4-7FF6-FD7FFC2485E8

treatment provided by

Plazi

scientific name

Oxynoemacheilus hazarensis Freyhof & Özuluğ, 2017
status

 

Oxynoemacheilus hazarensis Freyhof & Özuluğ, 2017  

( Fig. 5–6 View FIGURE 5 View FIGURE 6 )

Oxynoemacheilus hazarensis Freyhof & Özuluğ, 2017:379   , figs. 1–6 (type locality: Turkey: North-eastern shore of Lake Hazar, Elazığ province, 38°28.398‘N 39°18.093‘E).

Material examined. FFR 1487, 3, 51–63 mm SL; FFR 15526 View Materials , 9, 39–67 mm SL; Turkey, Elazığ prov.: lower stream Behremas, 38.501 39.509.— FSJF 2512, paratypes, 11, 44– 62 mm SL; Turkey: Elazığ prov.: north-eastern shore of Lake Hazar , 38.4733 39.3016 GoogleMaps   .

Material used in molecular genetic analysis. FSJF DNA 905; Turkey: Elazığ prov.: north-eastern shore of Lake Hazar, 38.4733 39.3016. (GenBank accession number: MK 546459 View Materials ). GoogleMaps   FSJF-DNA-1419; Turkey: Elazığ prov.: north-eastern shore of Lake Hazar , 38.4733 39.3016 (GenBank accession number: MK 546460 View Materials ) GoogleMaps  

.

Diagnosis. Oxynoemacheilus hazarensis   is distinguished from O. ercisianus   by having a suborbital groove in the male (vs. absent), the caudal peduncle behind the anus with scales (vs. scales absent), a more slender body (body depth at dorsal-fin origin 15–17% SL vs. 16–21), a more slender caudal peduncle (caudal peduncle length 1.3–1.5 times its depth vs. 1.0–1.3) and a shorter prepelvic distance (47–52% SL vs. 52–57).

Oxynoemacheilus hazarensis   is found together with O. kurdistanicus   in the stream Behremas, a tributary to Lake Hazer. It is distinguished from this species by having an incomplete lateral line in most individuals (vs. complete), a slightly emarginate caudal fin (vs. deeply emarginate or slightly forked), a deeper caudal peduncle (11–13% SL vs. 9–11 in O. kurdistanicus   ), and the back and the flank in front of the anus without scales (vs. scales present on entire back and flank).

Distribution. Oxynoemacheilus hazarensis   is endemic to Lake Hazer basin in the uppermost Tigris drainage.

Remarks. Our molecular data ( Fig. 1 View FIGURE 1 ) place O. hazarensis   in the O. tigris   species group. Based on DNA barcoding it is well separated from all other species in the O. tigris   group, with O. kaynaki   being the closest relative based on the DNA barcode data with a minimum K2P distance of 4.7% separating the two taxa. It is also supported by the PTP approach and by the mPTP delimitation as a distinct entity.

Oxynoemacheilus hazarensis   is the only species of the O. tigris   species group found in the Tigris River drainage. While we were unable to find published evidence for a past hydrological connection of Lake Hazer with the Euphrates drainage, the Lake Hazar basin is situated immediately adjacent to the Euphrates catchment and it seems very likely that the ancestor of O. hazarensis   found its way through a past connection from the Euphrates into Lake Hazar. On the other hand, many Oxynoemacheilus   species from the Tigris have quite restricted ranges and are locally endemic to one or few tributaries of the Tigris. As O. hazarensis   is the phylogenetic sister of the other species of the O. tigris   group, which are all found in the Euphrates (and Lake Van basin), we could also speculate that the common ancestor of the O. tigris   group invaded the Euphrates from the Tigris, maybe from Lake Hazer or its forerunners.

Oxynoemacheilus hazarensis   was described lacking a suborbital groove in the male but in additional material examined for this study, we found males having a suborbital groove. While the suborbital groove is a very stable and sound character in Oxynoemacheilus   loaches, it can only be seen in fully adult males. In the type series studied by Freyhof & Özuluğ (2017) there were only few fully grown individuals.

MK

National Museum of Kenya

Kingdom

Animalia

Phylum

Chordata

Class

Actinopterygii

Order

Cypriniformes

Family

Nemacheilidae

Genus

Oxynoemacheilus

Loc

Oxynoemacheilus hazarensis Freyhof & Özuluğ, 2017

Freyhof, Jörg, Kaya, Cüneyt, Turan, Davut & Geiger, Matthias 2019
2019
Loc

Oxynoemacheilus hazarensis Freyhof & Özuluğ, 2017:379

Freyhof & Ozulug 2017: 379
2017