Morphological differentiation of Artemia urmiana in four different geographical stations from the Urmia Lake West Azerbaijan Province, Iran
Alireza Asem1, Nasrullah Rastegar-Pouyani1, Naser Agh 2
1. Department of Biology, Faculty of Science, Razi University, Kermanshah, IRAN
2. Artemia and Aquatic Animals Research Center, Urmia University, Urmia, IRANSummary:
Brine shrimp Artemia is a tiny crustacean with cosmopolitan distribution. Artemia urmiana was first reported from the Lake Urmia by Gunther in 1899. The main objective of this study was to compare morphological differentiation between samples of Artemia urmiana from different stations with different ecological conditions. Thirty male and female samples of Artemia urmiana were randomly collected from four different harvesting sites in north, south and in the middle of the Urmia Lake (N2; M3-2; M1-2; S2). The rate of salinity was between 240 ppt – 285 ppt. Twelve morphological characters for males and thirteen for females were measured; and number of setae per furca were counted. Principal Components and Discriminant Function Analyses were used in order to classify these four stations. Male and female samples were analyzed separately because they are sexually dimorphic. Principal Components Analysis shows that male samples in N2, S2 and M2-3 stations were almost clustered in one group and this mixed group was separated from M1-2 station with regard to factor 1. This finding was also confirmed by Discriminant Function Analysis. In this analysis 100% of original groups were correctly classified between M1-2–M3-2, M1-2–N2 and M1-2–S2 stations. According to Principal Components Analysis the female samples were almost clustered in one group in all sites and it was not possible to make any separation among them. But Discriminant Function Analysis shows that M1-2 station was relatively separated from the other groups. In this analysis: i) 98.3% of original groups were correctly classified between M1-2–M3-2, ii) 91.7% of original groups were correctly classified between M1-2–N2, iii) 86.7% of original groups were correctly classified between M1-2–S2. Therefore, we suggest there are minimum two ecological populations of Artemia urmiana in Urmia Lake.
Fig. Classification of the male and female groups in each station by PCA and DA.
