Morphological variations of Alburnus mossulensis Heckel, 1843 populations in the Tigris tributaries of the Persian Gulf basin in Iran (Teleostei: Cyprinidae)

The genus Alburnus (Cyprinidae) is distributed in Europe and northern southwest Asia with about 38 species among which seven species are present in Iran. In this study 229 specimens of Alburnus mossulensis were collected from eight rivers of Tigris sub basin which drain into the Persian Gulf, and were fixed in %10 formalin for further investigation. Eighteen morphometric and 12 meristic characters of the each specimen and their weight were measured. Morphometric characters in ratio method and meristic characters in classification method were used for population comparison. Analysis of variance (ANOVA) showed significant differences (P<0.05) in all population in all morphometric characters, except interorbital depth/head width. Classification of meristic characters showed most specimens of all populations has eight soft rays in dorsal fin, 10 soft rays in anal fin, 19 soft rays in caudal fin, 15 soft rays in pectoral fin, nine soft rays in pelvic fin, 2.4.5-5.4.2 formula in Pharyngeal teeth type, and 42 vertebrae. ANOVA showed significant differences (P<0.05) in means of all meristic characters among the populations. DFA analysis showed a low degree of separation among four populations of Abdanan, Leileh, Little Zab and Shoisheh from each other, but high separation from other population and high separation among the other populations of A. mossulensis .