Molecular and morphological approaches in discrimination of endangered Probarbus jullieni of Malaysia and Thailand stocks.

The population structure of Probarbus jullieni from Malaysia and Thailand stocks was based on seven microsatellite primers and truss network measurements. Truss morphometric measurements were made on Temoleh, Probarbus jullieni to demonstrate the degree of speciation that can be induced by both biotic and abiotic conditions and contribute to the definition of different stocks of Probarbus sp. At the momment no relevant information on stock definition has been produced recently concerning Probarbus spp., which is now in IUCN threatened red list. We also summarize the possible discriminant morphological characteristics that shows differentiation between Malaysia and Thailand stocks. We also compare the levels of morphology and genetic differences for Malaysian stocks throughout one year of sampling to determine whether sampling season and possible sexual dimorphism can be detected in this fishes. A total of 25 different alleles were found across the two populations by the seven microsatellites, of which 21 and 19 alleles were detected in Pahang, Malaysia and Thailand, respectively At the population level, the mean number of alleles of Pahang (3.4991) per locus was higher than that (3.1665) of Thailand. From both molecular and morphometric measurements showed that there were two distinct populations. However the differences between these two populations showed that they belong to the same species with least degree of separation