Turcinoemacheilus ekmekciae, a new dwarf loach from Upper Tigris and Euphrates (Teleostei: Nemacheilidae).

Turcinoemacheilus ekmekciae, new species, from upper Euphrates and Tigris drainages is distinguished from other species of Turcinoemacheilus in Western Asia by having roundish blotches present throughout lateral line, usually not forming a mid-lateral stripe, 5-6 mandibular pores in mandibular canal, a smaller head, a deeper body and a greater pre-pelvic distance. Our specimens collected from the upper Great Zab, near the type locality of T. kosswigi, showed notable genetic divergence (a minimum K2P of 3.3%) from sequences reported by Esmaeili et al. (2014) as T. kosswigi. Despite morphological similarities, this molecular difference suggests that the populations analysed by Esmaeili et al. (2014) may represent a potential new species of Turcinoemacheilus, which we tentatively named as Turcinoemacheius cf. kosswigi. Molecular data also suggest that T. ekmekciae is characterized by a minimum K2P distance of 3.5% from T. minimus and T. cf. kosswigi. The three methods for species delimitation (ASAP, PTP, and mPTP) that were utilized for testing species assignments consistently identified our test group as a distinct species. This article is protected by copyright. All rights reserved.