Oxynoemacheilus fatmae, a new species from the Güzelhisar Stream in the Aegean Sea basin, Türkiye (Teleostei: Nemacheilidae).

Oxynoemacheilus fatmae, a new species, is found in the Güzelhisar Stream in the northern Aegean Sea basin. It is differentiated from all other species of Oxynoemacheilus in the northern Aegean Sea and adjacent basins by having four to eight irregularly shaped narrow black bars on the posterior part of flank, and anterior parts of the flank with a marbled pattern. O. fatmae is differentiated from the closest species Oxynoemacheilus theophilii by having 14 fixed diagnostic nucleotide substitution sites, and the pair-wise genetic distance is 2.22%. It further differs from O. theophilii by having a slenderer body (body at dorsal-fin origin: 15%-17% standard length [SL] vs. 17%-18%), a slenderer caudal peduncle (10%-12% SL vs. 12%-13%), a more forked caudal fin (length of middle caudal-fin lope: 16%-19% SL vs. 19%-23%), and the absence the dorsal and ventral adipose crests on the caudal peduncle behind the vertical of the posterior anal-fin base (vs. present). Three species delimitation tests (assemble species by automatic partitioning (ASAP), automatic barcode gap discovery (ABGD) and generalized mixed yule-coalescent (GMYC)) and phylogenetic analyses reinforce the validity of O. fatmae as a distinct species.

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 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.

Long-term investigation of microplastic abundance in Squalius species in Turkish inland waters.

Examining the enduring alterations in microplastic (MP) concentrations within fish in inland waters is of utmost importance in understanding the historical trajectory of plastic waste and formulating consequential predictions regarding upcoming pollution levels. This study includes the collection of fish samples from 22 different river basins in Türkiye and all Squalius species distributed in Türkiye, covering the years 2004-2018, and examined the presence of MP in museum specimens' gastrointestinal tracts (GITs). 331 specimens were examined, and microplastic was observed in 20.8% (69). A mean value of 0.27 ± 0.19 MP per individual was observed, resulting in a cumulative score of 91 MP. Most observed MPs were composed of fiber, representing 79.1% of the total. The polymer types identified were mostly polyethylene (PE) at 38.5% and polyethylene terephthalate (PET) at 29.7%. The black color was prominent among MPs, and MP length ranged between 101 and 4963 µm. The analysis revealed no statistically significant difference in the mean MP values across different years and basins. There is no substantial correlation between the abundance of MP and the sizes of fish, population density, or quantities of plastic production. The data indicate that MP has persistently acted as a contaminant in freshwater ecosystems over an extended period. It is projected that the laundering of synthetic textiles serves as the primary contributor to MP contamination in freshwater bodies. Our results offer significant baseline data on the pervasive issue of MP pollution in the freshwater environment. These findings enable us to gain profound insights into the current state of MP contamination in fish residing in lotic systems while empowering us to make accurate predictions about its future trajectory.

Oxynoemacheilus marmaraensis, a new species from the Susurluk River, Türkiye (Teleostei: Nemacheilidae).

Oxynoemacheilus marmaraensis, new species, is restricted to the Susurluk River. It is distinguished from all the named species of Oxynoemacheilus in the northwestern Anatolian by the flank with a vermiculate pattern and the presence of a suborbital groove in males, and no axillary lobe at the base of the pelvic fin. It also differs from the closest species, Oxynoemacheilus kentritensis, by having 58 nucleotide substitution sites. The genetic distance is 10.49% between O. marmaraensis and O. kentritensis. Phylogenetic analyses and species delimitation tests (Poisson tree processes and assemble species by automatic partitioning) support the validity of O. marmaraensis as a distinct species.

Phoxinus abanticus, a new species from the Lake Abant drainage in Türkiye (Teleostei: Leuciscidae).

Phoxinus abanticus, a new species, is described from the Lake Abant basin. It is distinguished from Phoxinus species in Türkiye and adjacent waters by the presence of fewer lateral line scales (60-69, vs. 75-91 in Phoxinus colchicus, 75-90 in Phoxinus strandjae); a deeper caudal peduncle (caudal peduncle depth: 1.8-2.3 times in length, vs. 2.4-2.9 in P. colchicus; 2.5-3.2 in P. strandjae); the absence of scales in the breast of males (vs. present); and ventral body reddish in nuptial colouration pattern for male (vs. brackish). The new species, P. abanticus, is also distinguished from its closest relative, P. strandjae, by a minimum of 3.40% genetic distance in the mtDNA cytochrome b (cyt b) gene.

Squalius cephaloides, a synonym of Squalius cii (Teleostei: Leuciscidae).

The two species hypothesis for S. cephaloides and S. cii, both occurring in the southern Marmara Sea basin, is tested. Our results suggested that there are no morphological and molecular characters to support this hypothesis, and we treat Squalius cephaloides as a junior synonym of S. cii.

The trouts of the upper Kura and Aras rivers in Turkey, with description of three new species (Teleostei: Salmonidae).

The taxonomic status of the resident and anadromous trout species native to the Kura and Aras river drainages is evaluated, and three resident species are recognised in the upper reaches of Kura and Aras drainages in Turkey. Salmo murathani, new species, is described from slow flowing tributaries of the Aras River. It is distinguished by the general body color dark greyish in life; the numerous black spots on body, present on the back and on the middle and upper parts of the flank, and on the anterior part of the lower flank in males and females larger than about 230 mm SL; the number of black spots increases with size, in both males and females; and various meristic and morphometric characters. Salmo araxensis, new species, is described from fast flowing tributaries of the Aras River. It is distinguished by the general body color greyish to brownish in life; only few black spots on the body, restricted to the back and the upper part of the flank, their number not increasing with size in both sexes; and various meristic and morphometric characters. Salmo ardahanensis, new species, is described from head waters of the Kura River. It is distinguished by the general body color dark brownish in life; the roundish black spots on the body, scattered on the back, and the middle and upper parts of the flank in most specimens, rarely restricted to the back and the upper part of the flank; in females, the black spots are few, restricted to the back and the upper part of the flank; the number of black spots increases slightly with size in males; the adipose fin is large, almost reaching to caudal-fin base in males larger than about 170 mm SL; and various meristic and morphometric characters.

DNA barcoding and species delimitation of the genus Oxynoemacheilus (Teleostei: Nemacheilidae) in Anatolia.

The DNA barcoding approach was used for the determination of evolutionary relationships and species delimitation of the genus Oxynoemacheilus (Teleostei: Nemacheilidae). The COI barcode region (615 bp amplicon) was used to barcode 444 individuals from 64 morphologically identified species in the genus Oxynoemacheilus and 189 haplotypes were identified. The average of the interspecific p distance (9.59%) was about 21-fold higher than the average intraspecific distance (0.44%). A general genetic threshold of 1.46% sequence divergence was defined for species delimitation. The multiple species delimitation methods (BCM, GMYC, bPTP and TCS) revealed a total of 62 molecular operational taxonomic units for 64 morphospecies with a new loach species from the BuyukMelen River. Neighbour-joining, maximum likelihood and Bayesian inference analyses indicated that all haplotypes were clustered into 62 clades, which corresponded to Oxynoemacheilus species, with strong bootstrap support (≥95%). Furthermore, all samples grouped in concurrence with the taxonomic status of the species except for species groups (O. germencicus-O. cinicus-O. mesudae and O. leontinae-O. namiri) that were showed intraspecific overlap in genetic diversity for COI-based barcodes. In conclusion, our analyses indicate that COI-based barcodes provide reliable species discrimination. Therefore, we currently recommend COI barcodes as the suitable barcode for genus Oxynoemacheilus.

Alburnus battalgilae, a synonym of A. attalus (Teleostei: Leuciscidae).

Alburnus battalgilae zulu Freyhof, 2007 from the Gediz River drainage in western Anatolia is a junior synonym of A. attalus zulu Freyhof, 2007, from the adjacent Bakr River drainage. We were unable to confirm the morphological differences originally proposed. As both species have been described in the same publication, as First Reviewers, we prioritise of A. attalus over A. battalgilae.

Illustrated type specimens catalogue of Recep Tayyip Erdogan University Zoology Museum of the Faculty of Fisheries.

The first type specimens catalogue of Recep Tayyip Erdogan University Zoology Museum of the Faculty of Fisheries, Rize (FFR) is presented. The catalog includes 3030 specimens from 249 lots, representing 55 holotypes and 2974 paratypes of 62 nominal species. Corrections and comments on the original descriptions are included in the remarks for each species if necessary. The current distribution range of all species is given. Photos of all holotypes and one paratype of each nominal species are presented to show the current condition of the types.

Turcichondrostoma, a new genus for the Leuciscidae (Teleostei: Cypriniformes) from Southwestern Anatolia.

Turcichondrostoma, a new genus, from the Southwestern Anatolia is distinguished by having fewer gill rakers on first gill arch and morphologies of premaxilla and dentary bones. In addition, as a result of the phylogenetic analyses based on combine data set (mtDNA COI + Cytb) sequences (1706 bp.), Turcichondrostoma genus was recovered with high posterior probability value (BI PP:1.0) and strong-supported bootstrap value (ML BP: 100%) among the former Chondrostoma groups. Also, high K2P mean genetic distance values (more than 7.84%) differentiated genus Turcichondrostoma from the other genera of former Chondrostoma group. The results of both morphological-osteological and molecular analyses are congruent with each other. The results of this study revealed that the genus Turcichondrostoma is easily distinguished from the genera in Chondrostoma group.

emGarra/em emorontesi/em, a new species from the Orontes River drainage (Teleostei: Cyprinidae).

Garra orontesi, new species, is described from the Orontes River drainage in the eastern Mediterranean Sea basin in Turkey and Syria. It is distinguished from its congeners in the Mediterranean Sea basin and adjacent Mesopotamia by possessing 17-21 gill rakers on the lower part of the first gill arch, the pelvic-fin origin usually below the second branched dorsal-fin ray, 8½ branched dorsal-fin rays, usually 2-3 scales between the tip of the pectoral and pelvic-fin origins, and no tubercles behind the upper posterior eye margin. It is also distinguished by a minimum K2P distance of 2.7% in its COI barcode region against G. rufa, and 3.9% against the geographically adjacent G. turcica.

Alburnus nasreddini, a synonym of A. escherichii (Teleostei: Leuciscidae).

Alburnus nasreddini described from Lake Eber in Central Anatolia is a junior synonym of A. escherichii, a widespread species in adjacent Sakarya River drainage. We found no morphological characters to distinguish Alburnus nasreddini from A. escherichii and both are poorly distinguished on a molecular level also.

Oxynoemacheilus cilicicus, a new nemacheilid loach from the Göksu River in southern Anatolia (Teleostei: Nemacheilidae).

Oxynoemacheilus cilicicus, new species, is described from the Göksu, Seyhan and Ceyhan rivers in southern Turkey. It is distinguished from other Oxynoemacheilus species in the Eastern Mediterranean Sea basin by possession of an incomplete lateral line, terminating before the vertical of the dorsal-fin origin or slightly behind the dorsal-fin base, a deeply emarginate caudal fin, no suborbital groove in male individuals, and a series of dark-brown bars on the flank not interrupted along the lateral line. Molecular data suggest that Oxynoemacheilus cilicicus is characterised by 22 variable nucleotide substitutions and a minimum K2P distance of 4.09% with O. panthera in the mtDNA COI barcode region.

The westernmost known population of Paracobitis (Teleostei, Nemacheilidae), with the description of a new species from the Euphrates River in southern Anatolia.

Paracobitis salihae, new species, from the Göksu River in the western upper Euphrates drainage, is distinguished from other Paracobitis species by possessing a truncate caudal-fin, and a dark-brown vermiculate or marbled colour pattern. It is also characterised by 19 variable nucleotide substitutions, three diagnostic nucleotides and 3.6% minimum K2P distance compared to geographically adjacent and related P. zabgawraensis. Paracobitis salihae might be Critically Endangered and is threatened by dam constructions.

Molecular systematics and phylogeography of the genus Alburnus Rafinesque, 1820 (Teleostei, Leuciscidae) in Turkey.

In this study, the phylogeny of Alburnus genus distributed in Turkish freshwaters was performed by analyzing mitochondrial cyt b gene (1141 bp) and COI gene (1551 bp) sequences from 1172 samples representing 112 populations of 24 species through their geographical distribution. According to our findings, 20 valid species are distributed in Turkey of which 18 have already been known. While six Alburnus species (A. battalgilae, A. istanbulensis, A. carinatus, A. schischkovi, A. nasreddini ve A. adanensis) have been synonomized, two new species (Alburnus sp.1 and Alburnus sp.2) from Dicle River and Çapraz Stream/Susurluk River have been identified. Extinct species such as A. akili and A. nicaeensis have not been observed in situ. Phylogenetic tree topologies and haplotype network of the 119 cyt b and 80 COI haplotypes detected in Alburnus species have indicated a consensus tree topology containing twenty lineages, each of corresponding to one species, and three Alburnus haplogroups corresponding to the geographical origins: Eastern Anatolia (I), Mediterranean (2) and Western & Northern Anatolia (3). The results indicate that the divergence between those haplogroups may have occurred during the Middle Miocene-Middle Pleistocene periods (from 14.9 to 5.29 million years).

A new species of trout from the northern drainages of Euphrates River, Turkey (Salmoniformes: Salmonidae).

Salmo fahrettini, a new species, is distributed in the northern tributaries of the Euphrates River. It differs from other Salmo species in adjacent waters by a combination of the following characters: a greyish body; one black spot behind the eye and on the cheek; three to six black spots on the opercle; numerous black spots on the back (missing on the predorsal area), flank and middle part of body, surrounded by a roundish white ring; red spots in the median part of the body, surrounded by a roundish white ring; short and narrow maxilla; increase in the number of black and red spots with an increase in size; adipose fin medium size, no or rarely one red spot at its posterior edge; 109-116 lateral line scales; 27-30 scale rows between dorsal-fin origin and lateral line; 20-23 scale rows between the lateral line and anal-fin origin; maxilla length 8.8-10.0% standard length in males, 8.8-9.6 in females.

Barbus xanthos, a new barbel from the Southern Aegean basin (Teleostei: Cyprinidae).

Barbus xanthos, a new species, is described from the Esen, Dalaman, Tersakan and Büyük Menderes rivers in south-western Anatolia. It differs from other Barbus species in the adjacent basins by having 53-60 lateral line scales, a weakly ossified last unbranched dorsal-fin ray (about 33-50%), numerous small irregular-shaped black or dark-brown spots smaller than scales, often forming large, black or dark-brown blotches on back and flank in juveniles and adults, and a straight or slightly convex posterior dorsal-fin margin. B. xanthos differs from its most closely related congener, B. pergamonensis, by nine nucleotide substitution sites in the mitochondrial DNA cytochrome oxidase I barcode region.

Review of the Oxynoemacheilus tigris group with the description of two new species from the Euphrates drainage (Teleostei: Nemacheilidae).

The Oxynoemacheilus tigris species group is reviewed, resulting in the recognition of six species, of which two are described herein as new. Oxynoemacheilus tigris is known from the endorheic Qweik River and the Merziman River, which is a tributary of the western Euphrates. Oxynoemacheilus ercisianus is endemic to the endorheic Lake Van basin and O. hazarensis is endemic to Lake Hazar basin in the upper Tigris drainage. Oxynoemacheilus kaynaki is widespread in the Euphrates drainage. The two undescribed species occur in the Euphrates drainage. Oxynoemacheilus arsaniasus, new species, from the Murat River and the upper Karasu (Mus) River drainage, is distinguished from other species of the O. tigris group by having a bold, black, irregularly-shaped bar at the caudal-fin base, an incomplete lateral line and a scaleless body. Oxynoemacheilus muefiti, new species, from the upper Murat River drainage and a tributary to the Atatürk reservoir, is most similar to O. ercisianus, from which it is distinguished by a more slender body and a shallower dorsal adipose crest. According to our molecular data, the Qweik population of O. tigris is suspected to be introgressed by O. namiri from the Orontes drainage. Oxynoemacheilus erdali is identified as a synonym of O. bergianus as we were unable to find differences between the two species.

Phylogeny and phylogeography of the genus Alburnoides (Teleostei, Cyprinidae) in Turkey based on mitochondrial DNA sequences.

Turkey has a rich freshwater biodiversity in terms of Cyprinid genus in respect to its geographical location. To elucidate the phylogeny of the Alburnoides genus, one of these genera, genetic data for the cytochrome b gene (1141 bp) was generated for 445 samples collected at 42 sampling sites across their geographical distribution. A total of 54 mitochondrial haplotypes identified were distrubuted among distinct twelve species that did not share haplotypes with each other. Pairwise sequence divergence among these species range from 1.37% (A. emineae and A. velioglui) and 10.99% (A. manyasensis and A. smyrnae). A new potential species in the River Dirgine that run into the Black Sea Basin was separated from the most closed known species with mean 6.3%. Network analysis and phylogenetic analysis indicated that all haplotypes were clustered into two major clades, which corresponded to twenty-three Alburnoides lineages, with moderate-high bootstrap supports and mutational steps, respectively. Application of a molecular clock to a Bayesian phylogeny indicates that Alburnoides diversified under the paleogeographic conditions such as tectonic uplift and faulting Miocene aged as well as climatic oscillation and sea-level fluctuations during late Miocene-middle Pleistocene. The genetic results of the present study indicated the inter-specific distance of cyt b gene sequences followed the ideal results for species identification and phylogeny of Turkish spirlins.