Genetic connectivity and phenotypic plasticity in the cyprinodont Aphanius farsicus from the Maharlu Basin, south-western Iran

Meristic and morphometric characteristics, including otolith data, of the Farsi tooth-carp Aphanius farsicus, which is endemic to the endorheic Maharlu Basin in south-western Iran, were analysed for a sample of 92 individuals from four spring-streams; DNA sequence data (cytochrome b gene) are presented for 29 specimens. Some phenotypic variation was detected but the genetic data clearly indicate connectivity between the populations. Possible links between phenotypic variation and environmental variables such as water temperature, habitat size and absence or presence of predators and competitors are discussed. Based on a literature survey and the new data, it is concluded that population connectivity is maintained during times of droughts via large aquifers that formed during the late Pliocene to early Pleistocene, when the extant endorheic Maharlu Basin was created. Based on new data presented here and previous work, it is apparent that plastic and constant characteristics are present in Aphanius species, and that, if a population becomes isolated, a given trend of evolution may give rise to a taxonomically useful characteristic.

Occurrence of Clinostomum complanatum in Aphanius dispar (Actinoptrygii: Cyprinodontidae) collected from Mehran River, Hormuzgan Province, South of Iran

OBJECTIVE

To investigate the possibility of Aphanius dispar (A.dispar) acting as intermediate host for Clinostomum complanatum (C. complanatum), from Mehran River, Hormuzgan Province of Iran.

METHODS

During a biological study of A. dispar in Mehran River, Hormuzgan Province, South of Iran, a total of 97 fish specimens were collected in 24 January 2006.

RESULTS

4 specimens (4.12%) including 1 male and 3 female were found infected with C. complanatum metacercaria. These metacercaria were coiled in the epiderm on the body surface of infected fishes. The infection is known as yellow spot disease. The parasite abundance, intensity and prevalence were 0.05%, 1.25% and 4.12%, respectively. The infection was higher in females than males.

CONCLUSIONS

To the best of our knowledge, this is the first report on occurrence of C. complanatum metacercaria in A. dispar in Iran.