Luciobarbus lydianus and L. kottelati, two synonyms of L. graecus (Teleostei: Cyprinidae).

The Aegean Luciobarbus graecus, L. lydianus, and L. kottelati were described based on morphological characters. However, re-examination of fresh material from the three species revealed greater intraspecific variability in morphological character states, and wider overlaps in all postulated diagnostic traits than initially documented. Consequently, it is not possible to identify and distinguish these three species based solely on morphological characteristics. As they also share identical COI barcode sequences, these species are now considered conspecifics, and L. lydianus and L. kottelati are treated as junior synonyms of L. graecus. The distribution of L. graecus remains a biogeographical puzzle, and it cannot be excluded that this could be partly human-mediated. Population-level genomic studies, particularly those focusing on phylogeography and population genetics, may help clarify mechanisms underlying contemporary distribution of this species.

Turcinoemacheilus inexpectatus, a new nemacheilid loach from the Tigris drainage (Teleostei: Nemacheilidae).

Turcinoemacheilus inexpectatus, new species, is described from the Greater Zab, Lesser Zab, and Sirvan drainages, all tributaries of the middle Tigris. It belongs to the T. kosswigi species group. The new species is distinguished from its congeners by an indistinct or prominent midlateral stripe broader than the eye diameter often overlaid by a row of dark-brown blotches, greater pre-pelvic distance, deeper caudal peduncle, and wider interorbital distance.

Cabdio occidentalis, a new species from Lake Mashkid basin and the Makran region (Teleostei: Danionidae).

Cabdio occidentalis, new species, is described from the Lake Mashkid basin and the Makran region of Iran. It is distinguished from other species of the genus by a combination of characters: 3842+12 total lateral-line scales, 1923 predorsal scales, 911 pectoral-fin rays, and the absence of a keel between the pelvic-fin base and the genital papilla. The cytochrome c oxidase subunit I (COI) sequence separates C. occidentalis from C. morar, its closest congener, by a p-distance of 5.5%.

Revision of the Oxynoemacheilus angorae group with the description of two new species (Teleostei: Nemacheilidae).

The Oxynoemacheilus angorae species group is revised and 10 species are recognised, two of which are described herein as new. Oxynoemacheilus anatolicus, O. angorae, O. eregliensis, O. germencicus, O. isauricus, O. nasreddini, O. mediterraneus, and O. theophilii are endemic to west and Central Anatolia. Oxynoemacheilus cinicus and O. mesudae, both from Byk Menderes River drainage, are synonyms of O. germencicus. As First Revisers, we give priority to Oxynoemacheilus germencicus over O. cinicus. Oxynoemacheilus atili described from Lake Beyehir basin is a synonym of O. eregliensis. Oxynoemacheilus axylos, new species, from endorheic Lake Tuz basin (Cihanbeyli, Glyaz, Melendiz, and Samsam) is distinguished by possessing an almost truncate caudal-fin, a stout caudal peduncle, and elevated dorsal and ventral adipose crests. The new species is also distinguished by a minimum K2P sequence divergence of 1.6% in the mtDNA-COI barcode region from O. eregliensis, its closest relative. Oxynoemacheilus eliasi, new species, from the Kk Menderes and Gediz River drainages, is distinguished by having small, embedded scales on the belly, a narrow suborbital groove in male, an emarginate caudal fin, the caudal peduncle depth 1.31.5 times in its length, and the body depth decreasing between the dorsal and caudal-fin bases. The new species is also distinguished by a minimum K2P sequence divergence of 2.7% in the mtDNA-COI barcode region from O. theophilii, its closest relative.

A practical approach to revise the Oxynoemacheilus bergianus species group (Teleostei: Nemacheilidae).

The Oxynoemacheilus bergianus species group is revised based on tree topology (ML, NJ, MP), distance (K2P and ASAP) and Poisson tree process analyses of DNA barcode data tested against morphometric and morphological characters including colour patterns. The O. bergianus species group is distinguished from other Oxynoemacheilus groups based on morphological characters: its constituent species have a slender caudal peduncle, a suborbital flap in the male, a mottled or blotched colour pattern, and lack bold, black spots on the caudal-fin base. It is also supported as a monophyletic unit in our molecular analysis. The O. bergianus group includes 10 molecular clades following congruently well-supported NJ, MP and ML based entities. Species described as O. bergianus, O. banarescui, O. erdali, O. fatsaensis, O. samanticus, and O. simavicus from Turkey, O. lenkoranensis from Azerbaijan, and O. longipinnis and O. parvinae from Iran belong to this species group. The group includes also four unnamed molecular clades. We were unable to detect external differences between any of the molecular clades in colour pattern or any morphometric or morphological characters examined. In the 10 molecular clades in the O. bergianus species group, the intraclade K2P distance ranges from 0.01.8% while the distances between molecular clades ranges from 0.65.9%. To resolve the species diversity of this group, we also analysed the intraspecific and interspecific variability in the K2P distance of DNA barcode data from 53 other Oxynoemacheilus species. Here, the intraspecific variability ranges from 0.02.4% while the interspecific K2P distance ranges from 1.220.8%. In the O. bergianus species group, only four groups are detected by the mPTP species delimitation approach distinguished by a K2P distance of 2.9% or more. We treat these four groups as valid species, corresponding to O. banarescui, O. bergianus, O. fatsaensis, and O. simavicus. Oxynoemacheilus samanticus from the Kzlrmak and Seyhan drainages, O. lenkoranensis from the Caspian basin, O. erdali from the Euphrates, and O. longipinnis and O. parvinae from the Tigris drainage are treated as synonyms of O. bergianus. Fishes from an unnamed molecular clade from the upper Tigris, and from a second unnamed clade from the upper Euphrates, are both identified as O. bergianus. Oxynoemacheilus bergianus might be a junior synonym of O. bergi from the Kura. The distribution range of O. simavicus, described from the Simav drainage in the Marmara basin, is expanded to the east and two molecularly differentiated population groups occur in the Sakarya drainage, the Byk Melen River and potentially in other adjacent coastal streams. Oxynoemacheilus fatsaensis, described from the coastal stream Eleki in northern Anatolia, is also widespread in the Yeilrmak drainage. Morphological characters proposed to distinguish O. fatsaensis from the other species of the O. bergianus group could not be confirmed by our data on fishes from the Yeilrmak. This study also discusses the theoretical background, our reasons for conducting this revision in the way we did, and what the alternatives would be.

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.

Cobitis indus, a new spined loach from the Dalaman River in the Eastern Aegean Sea basin (Teleostei: Cobitidae).

Cobitis indus, new species, from the Dalaman River drainage, is distinguished from other Cobitis species in the eastern Aegean Sea basin by having two laminae circularis, a bifurcate suborbital spine, a narrow caudal peduncle, pigmentation zone 4 with 1724 small blotches often fused into a stripe, pigmentation below Z4 usually absent, and one black, comma-shaped spot at the upper caudal-fin base. It is further distinguished from its closest relative, C. dorademiri, by having 13 diagnostic nucleotide substitutions in the mtDNA COI barcode region and a K2P nearestneighbour distance of 2.32.7%. This is the fourth Cobitis species found in the Dalaman River drainage making this river the most species-rich in spined loaches in the Middle East.

Egirdira, a new generic name for Pararhodeus niger Kosswig amp; Geldiay, 1952 (Teleostei: Leuciscidae).

Egirdira, new genus, is proposed for Pararhodeus niger from Central Anatolia based on its position in molecular phylogenetic analyses and its morphological characters. It is distinguished from all other genera of Leuciscidae except Delminichthys and Pelasgus by having the unbranched part of pectoral rays 23 thickened and slanted upward, with a conspicuous downward angle at the distal end of the thickened part, no or an incomplete lateral line, and the genital papilla of the female not protruding. An unambiguous, unique morphological character distinguishing Egirdira from Pelasgus has not been identified, except that Egirdira has numerous isolated silvery scales (or patches of such scales) on the flank. A combination of characters distinguishes Egirdira from individual species of Pelasgus. Phoxinellus egridiri is a junior synonym of Pararhodeus niger.

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.

Five new species of the sisorid catfish genus Glyptothorax from Iran (Teleostei: Sisoridae).

Five new species of Glyptothorax are described from Iran. Glyptothorax alidaeii, new species, from the Seimare in the Karkheh drainage, G. galaxias, new species, from the upper Karun drainage, G. hosseinpanahii, new species, from the Zohreh drainage, G. pallens, new species, from the Sirvan drainage, and G. shapuri, new species, from Shapur in the Helleh drainage. Glyptothorax silviae from the Jarrahi drainage is re-diagnosed. All six species are morphologically distinguishable by the structure of the thoracic adhesive apparatus, as well as morphometric characters and details in the colour pattern. They form distinct mitochondrial clades between 1.2% and 4.1% minimum K2P distance based on the mitochondrial DNA barcode region.