Revision of the Oxynoemacheilus angorae group with the description of two new species (Teleostei: Nemacheilidae) Author Yoğurtçuoğlu, Baran Hacettepe University, Faculty of Science, Biology Department, Beytepe Campus, 06800 Ankara, Turkey. Author Kaya, Cüneyt Recep Tayyip Erdogan University, Faculty of Fisheries, 53100 Rize, Turkey. Author Freyhof, Jörg 0000-0002-7042-3127 Museum für Naturkunde, Leibniz Institute for Evolution and Biodiversity Science, 10115 Berlin, Germany. joerg. freyhof @ mfn. berlin; https: // orcid. org / 0000 - 0002 - 7042 - 3127 joerg.freyhof@mfn.berlin text Zootaxa 2022 2022-05-06 5133 4 451 485 journal article 55627 10.11646/zootaxa.5133.4.1 c2f66f44-2174-4c3a-82b5-288255ca2cb1 1175-5326 6530889 58A39822-32D1-4907-A866-7E75E5DA70A2 Oxynoemacheilus isauricus Yoğurtçuoğlu, Kaya, Özuluğ & Freyhof 2021 ( Fig. 10 ) Oxynoemacheilus isauricus Yoğurtçuoğlu, Kaya, Özuluğ & Freyhof 2021:372 , Figs. 2–4 ( type locality: Lake Beyşehir Basin , stream Çeltek at Çeltek , south of Şarkikaraağac , 38.0124 31.3152 ) Material examined. IUSHM 2021-1425 , holotype , 63 mm SL ; IUSHM 2021-1463 , paratypes , 48–53 mm SL; Turkey : Isparta prov. : Çeltek stream at Çeltek , south of Şarkikaraağaç , 38.0124 31.3152 .— FFR 1534, 9, 46–56 mm SL; Turkey : Konya prov. : Akçay stream at Gökçehüyük , 3 km west of Seydişehir , 37.4396 31.8000 . Diagnosis. Oxynoemacheilus isauricus is distinguished from all other species of the O. angorae group by having a very slender caudal peduncle (caudal peduncle depth 2.2–2.6 times in its length vs. 1.3–1.6 in O. anatolicus , 1.5–1.8 in O. angorae and O. germencicus , and 1.5–1.9 in O. eregliensis ; see details for other species below). It is further differentiated from O. anatolicus , O. angorae and O. eregliensis by possession of a shorter head (head length 21–24% SL vs. 24–27 in O. anatolicus ; 23–26 in O. angorae and 24–26 in O. eregliensis ), a moderately deep emarginate caudal fin (vs. slightly emarginate or almost truncate) in which the shortest middle caudal-fin ray is 71–85% of the longest ray of the upper caudal-fin lobe (vs. 84–93 in O. anatolicus ; 88–92 in O. angorae and 83–91 in O. eregliensis ), and no depigmented stripe along the anterior part of the lateral line (vs. present in O. angorae ). Oxynoemacheilus isauricus is further distinguished from O. germencicus by lacking scales on the belly (vs. present). Distribution. Oxynoemacheilus isauricus is known from Lake Beyşehir and Suğla basins in Central Anatolia Remarks. Based on DNA barcoding, O. isauricus is well separated by a minimum K2P sequence divergence of 7.5% and 8.0% in the mtDNA-COI barcode region from O. axylos and O. eregliensis , its closest relatives. It is also supported to be a distinct species by the PTP approach, and by the mPTP delimitation.