In this study, nucleolar organizer regions of Chalcalburnus mossulensis were investigated. Analysis of karyotypes revealed that the diploid numbers of chromosomes was 2n=50. There were six pairs of metacentric, eight pairs of submetacentric, five pairs of subtelocentric and six pairs of acrocentric chromosomes in the karyotype. It was shown that C. mossulensis possessed two pairs of nucleolar organizer regions-bearing chromosomes. One nucleolar organizer region was located terminally on the longer arm of a larger sized submetacentric chromosome, whereas the other nucleolar organizer region was located terminally on the short arm of a medium sized submetacentric chromosome. There was no significant difference in chromosomal nucleolar organizer region phenotypes and in number of nucleolar organizer regions among localities. Our results were compared with previous results of other researchers.

Giemsa staining, C-and AgNOR-banding procedures. Diploid chromosome numbers of analyzed species were found to be the same (2n = 50) but their karyotypes formulae were different. For all species examined, the largest chromosome pair of the complements was subtelo-acrocentric. Heteromorphic sex chromosomes were not detected in any of the studied species. C-bands were found on the centromeres of several chromosomes in all studied species. NORs were detected in one pair of submetacentric chromosomes in P. burduricus, P. egridiri and P. fahrettini, and in two pairs of submetacentric chromosomes in P. battalgilae, P. evliyae and P. maeandri. Further, NOR polymorphisms were observed in some specimens of P. battalgilae, P. burduricus, P. evliyae and P. fahrettini for number, location and size. This study may contribute to other leuciscine cytogenetic studies.

The karyotype and major ribosomal sites as revealed using silver staining of Anatolian leuciscine cyprinid fish Acanthobrama marmid were studied. The diploid chromosome number was invariably 2n = 50. Karyotype consisted of eight pairs of metacentric, 13 pairs of submetacentric and four pairs of subtelocentric to acrocentric chromosomes. The largest chromosome pair of the complement was subtelo-to acrocentric characteristically, which is a characteristic cytotaxonomic marker for representatives of the cyprinid lineage Leuciscinae. The nucleolar organizer regions (NORs) were detected in the telomeres of two pairs of medium sized submeta-to subtelocentric chromosomes. No heteromorphic sex chromosomes were found. The karyotype pattern of A. marmid is nearly identical to that found in most other representatives of the Eurasian leuciscine cyprinids, while the multiple NOR phenotype appears to be more derived as opposed to a uniform one, ubiquitous in this group.

This investigation was undertaken in order to provide some explanation in chromosomal polymorphism which is widely observed among the members of genus Spalax and also, an attempt was made to elucidate the speciation in this genus. 47 specimens of the mole rat from lower Euphrates were studied; of these, 18 specimens, taken from the east of the river, namely from Sanhurfa, were identified as S. ehrenbergi kirgisorum. The remaining 29 specimens, collected from the west of river, namely Adtyaman and Gaziantep, were identified as Spalax ehrenbergi intermedius. By the analysis of the karyotype, two karyotypic forms of S.e. kirgisorum (2n =52, NF = 76 and 2n =54, NF = 76) were found. Similarly, two karyotypic forms of S.e. intermedius (2n =52, NF = 76 and 2n =56, NF = 90) were established. The phylogenie relations of the karyotypic forms and evolutionary relationship between subspecies were discussed.

The genus Pseudophoxinus Bleeker, 1860 is found in a wide range of habitats in central Anatolia, but it is not well known from a cytogenetic aspect. In this study the first karyotypic description of the spring minnows Pseudophoxinus crassus (Ladiges, 1960) and Pseudophoxinus hittitorum Freyhof & Özulug, 2010 by means of conventional methods (Giemsa staining, C-banding, silver nitrate impregnation (Ag-NORs)) was performed. Both species are endemic and have restricted distributions in Central Anatolia. Pseudophoxinus crassus and Pseudophoxinus hittitorum have the same diploid chromosome number, 2n = 50, patterns of distribution of constitutive heterochromatin (CH), and localization of nucleolus organizer regions (NORs), but differ in their karyotypic formulae (KFs). The C-banding technique revealed clear pericentromeric blocks of CH in many chromosomes; Ag-NORs treatment revealed consistent positive signals at the end of the short arms of a submetacentric chromosome pair, likely homologous in both species. The karyotypic differences found between these species can be used for their taxonomical study.