Application of Molecular Phylogeny and Bioinformatics for Identification of Cryptic Species in a Community.

Molecular markers like mtDNACOI have proved their identification efficiency in discriminating closely related species which may possibly have a vital effect on biodiversity estimation.Traditional methods based on morphology often fail to identify closely related species causing an over or under estimation of biodiversity. Studies have demonstrated that marine fauna exhibits high degree of cryptism. Thus, a lot of species either remain unidentified or have been identified erroneously. Present study involves the morphological identification of a group of limpet species found in the intertidal zones of Saurashtra coastline Gujarat followed by their COI gene sequence analysis. They were identified as Cellana karachiensis.Interestingly the three sample types: X, Y and Z, sharing the same habitat not only exhibit clear variations in their shell banding pattern but also show minor variations in their COI gene sequence. A total of six COI gene haplotypes were found using DnaSP version 5. A striking association of COI haplotypes to specific morphotypes was seen. Construction of phylogenetic tree using Mr. Bayes 3.2 clarifies the phylogenetic relationships of these samples indicating a split of lineages. This intriguing observation has put forth many possibilities. Is this plasticity due to polymorphism? Could they be a complex of cryptic species undergoing sympatric or peripatric speciation? It is also possible that they had been geographically isolated earlier and after genetic divergence occurred, came back to same location. This study thus points towards the need to reinvent an accurate baseline database of marine speciesand highlights the potential of molecular taxonomy in distinguishing between closely related species. [ABSTRACT FROM AUTHOR]