تفاوت هاي درون گونه اي Pontogammarus maeoticus در سواحل جنوبي درياي خزر

Intraspecific variations of Pontogammarus maeoticus (Sowinsky, 1894) in the Southern part of the Caspian Sea, Iran

In the Caspian Sea Amphipoda Constitute the most important food items for many commercial fishes such as sturgeons. Pontogammarus maeoticus is the most abundant food source and the most widespread species in the sublittora] zone of the southern coastal waters of the Caspian sea. In this study, tour stations were chosen in the southern coast of die Caspian Sea: I. Asura ( 38°, 30ʹ N , 4«\ 55ʹli) 2 bandar Anzali (37°, 28ʹ N, 49°, 28ʹ E) .1. Noshahr ( 36°, 42* N , 5l\ 26ʹ E) 4. Sari (36 ,59ʹ N, 52°,59ʹE). The sampling was undertaken fwrween April and September 2003 with the aid of a Dip net. All the specimens were Fixed in 70% Ethilic alcohol. 44 characters (40 Morphometeric and 4 Meristic) were measured for 30 specimens (15 male, 15 female) in each population using a microscope fitted with micrometer lense. T-test analysis showed significant differences in just 15 out of 60 characters, therefore the two sexes are almost similar. ANOVA showed a significant difference in 38 out of 60 characters among four of the populations studied. The results of PCA and clustering analysis showed that the Bandar Anzali population stood out far from the other populations due to its morphological differences.