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

Abstract

Turcinoemacheilus ekmekciae, new species, from upper Euphrates and Tigris drainages is distinguished from other species of Turcinoemacheilus in Western Asia by having a dark stripe broader than the eye diameter along the lateral line, rarely possessing roundish blotches, 5–6 mandibular pores in mandibular canal, a comperatvely smaller head, a deeper body, and a greater pre‐pelvic distance. Our specimens collected from the upper Great Zab, near the type locality of Turcinoemacheilus kosswigi, showed notable genetic divergence (a minimum K2P of 3.3%) from sequences reported as T. kosswigi in previous studies. Despite morphological similarities, this molecular difference suggests that the populations analysed in previous studies 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 Turcinoemacheilus minimus and T. cf. kosswigi. The three methods for species delimitation (assemble species by automatic partitioning [ASAP], Poisson tree processes [PTP], and multi‐rate PTP [mPTP]) that were utilized for testing species assignments consistently identified our test group as a distinct species.

Integrative Taxonomy of Turcinoemacheilus Bănărescu & Nalbant, 1964 in West Asia with the Description of Three New Species (Teleostei: Nemacheilidae)

“…The final alignment consisted of 701 base pairs, with 484 positions being constant, 163 being parsimony informative, and 23 being singletons (considering only the in-group). The resulting tree topology is, in general, in agreement with previously published phylogenies that included samples of Turcinoemacheilus [9,10]. Both the BI and ML methods resulted in a similar tree (Figure 2), recovering 10 well-supported clades corresponding to 10 species in the Turcinoemacheilus genus: T. ansari sp.…”

“…The samples used for molecular analyses were fixed in 99% EtOH (whole or a fin clip) after being euthanized. The species were identified following the original description and revisions of the genus [9,10].…”

“…The distribution map (Figure 1) was created with QGIS v.3.18 software (http://qgis.org, accessed on 10 October 2023). Morphometric data for T. ekmekciae Kaya, Yo gurtçuo glu, Aksu, Bayçelebi & Turan, 2023, T. kosswigi, and T. minimus Esmaeili, Sayyadzadeh, Özulu g, Geiger & Freyhof, 2014 [9] were obtained from Kaya et al [10].…”

Decadal‐scale regional variability in monitoring efforts significantly influences fish diversity trends in the Euphrates and Tigris catchments, Türkiye

“…The considerable share of the ichthyofauna of the Upper Euphrates and Tigris catchments had been identified after the 2000s, especially with the acceleration of genetically supported taxonomic studies. In fact, following the increased attention given to both catchments in the past two decades, 25 species have been described (Table S3) and Turcinoemacheilus ekmekciae, Turcinoemacheilus minimus) have even been described in the last 10 years alone (Turan et al, 2021;Turan et al, 2016;Turan et al, 2020;Freyhof et al, 2017;Freyhof, Kaya, & Ali, 2021;Mousavi-Sabet et al, 2022;Kaya, Imre, & Kurtul, 2024;Kaya, Yo gurtçuo glu, et al, 2024). However, the identification of new species differed between both catchments.…”

“…This is problematic, as a lack of information on biodiversity will ultimately result in the loss of numerous species and, with them, a loss of ecosystem functions and a plethora of important aspects for human well-being (Laureto et al, 2015). The lack of coherently and recurrently sampled sites spanning both catchments as well as interest in these two catchments' native biodiversity started to uptake only in recent years (Kaya et al, 2016;Kaya, Yo gurtçuo glu, et al, 2024). As such, it is possible that certain species, and with them important biological or ecological traits and ecosystem functions, have been lost without notice (Freyhof et al, 2014).…”