Leuciscidae

4.10 | Leuciscidae

Alburnoides samii was found by Levin, Simonov, Matveyev, et al. (2018) in the Lenkoran River in Azerbaijan. Future studies might show that some Alburnoides populations in rivers and streams south of the Kura and Aras drainages belong to this species.

Alburnus chalcoides is widespread in Azerbaijan and Georgian part of the Kura basin. It is also expected to occur in the Armenia (the Aras River) but has not yet been recorded here.

Rutilus caspicus from the Caspian Sea basin, R. heckelii from the Black Sea basin, and R. shelkovnikovi from the Metsamor River in the Ararat Valley (Armenia) were synonymised with R. lacustris based on their mtDNA identity ( Levin et al., 2017). This opinion is followed here.

Rutilus kutum is treated as a valid species by Bogutskaya and Iliadou (2006: 294) and following authors without a detailed discussion. The gene trees presented by Kotlík et al. (2008) showed clear geographical structure between the Black and Caspian Sea populations but the two populations were not reciprocally monophyletic at any of the three loci studied and there had been considerable gene flow suggested from the Caspian population into the Black Sea population. Own (unpublished) molecular data (COI) fail to distinguish the Caspian R. kutum from the Black Sea Rutilus frisii . We were unable to find evidence why both species should be separated despite that they are frequently listed in un-commented checklists. Therefore, we treat both populations as conspecific, R. kutum being a junior synonym of R. frisii .

Rutilus sojuchbulagi was known only from the Akstafa Region in Azerbaijan where it has not been found despite of intensive fieldwork and specific research during the last ten years. Therefore, we assume that this species has gone extinct. R. atropatenus and R. sojuchbulagi from Azerbaijan were initially described as members of the genus Rutilus ( Abdurakhmanov, 1950; Derzhavin, 1937) but later placed in Pseudophoxinus by Bogutskaya, Küçük, and Atalay (2006) without detailed discussion or arguments. Saç, Özuluğ, Geiger, and Freyhof (2019) place both species back to Rutilus based on molecular COI sequence data confirming the original generic placement ( Abdurakhmanov, 1950; Derzhavin, 1937) Future research based on nuclear molecular data might again challenge this placement.

Squalius agdamicus was described from a small river called the Kuyra at Agdam town, not reaching the Kura River ( Berg, 1949). Doadrio and Caramona (2006) treat this species as valid and our own (unpublished) data strongly suggest that it is widespread all over the Kura River drainage, but there is no indication, that it also occur in the Aras, where it is replaced by Squalius turcicus .

Squalius orientalis is treated as a valid species restricted to the eastern Black Sea basin (Khaefi, Esmaeili, Sayyadzadeh, Geiger, & Freyhof, 2016) and identifications are largely based on the COI gene of Squalius from the Ashe River in Russia,south to the Coruh River in Turkey. Its distribution range might be much larger and this molecular lineage is very closely related to a molecular lineage that is widely distributed in the northern Black Sea basin as well as in the Baltic Sea basin west to the Elbe River in the Czech Republic and Germany, where it is identified as S. cephalus .

Squalius turcicus was described from the upper Aras River in Turkey. Özulug and Freyhof (2011) suggested that this might be the species distributed in the southern Caspian Sea basin. Turan, Kottelat, and Doǧan (2013) treat S. turcicus as a distinct species from S. orientalis . Also Khaefi et al. (2016) treat S. turcicus as a valid species. Accordingly, all previous notes on Squalius species from Aras river is treated as S. turcicus . As of now, there is no comprehensive distribution data available for S. turcicus and S. agdamicus in the Caspian Sea drainage and they might frequently live in sympatry. Apparently, more data is needed to better understand the distribution of these two species.