MOLECULAR ECOLOGY OF FRESHWATER TURTLES AND FUTURE DIRECTIONS

Abstract

The distribution and diversity of turtles now reflect the lengthy and complex evolution of the taxonomy, which represents an old group of tetrapod vertebrates in terms of evolutionary history. Freshwater turtles represent the majority of the 365 species, and they mostly live in tropical and subtropical regions. Emydidae diversity hotspots can be found in Southeast North America, as can Geoemydidae and Trionychidae in the Indo-Malayan area. While Pelomedusidae are mostly found in Africa, Chelidae are primarily found in the Neotropics and Australia. Most species of the genus are endemic to a particular region or even to a single location. The majority of freshwater turtles suffer varied degrees of threat, mostly from habitat changes and collection. With the use of morphological and molecular data, the majority of phylogenetic trees for different turtle species have been generated using DNA techniques and procedures. The complete mitochondrial DNA (mtDNA), dehydrogenase subunit 4 (ND4), cytochrome b (Cyt b), carapacial ridge (CR), and cytochrome c oxidase subunit I (CO I) genes of freshwater turtles were sequenced by using universal PCR and long-PCR methods. Along with CR sequences of freshwater turtles, the composition and structure of the control region of diverse species were compared and analysed. Functional domains in the regulatory area, as well as their conserved sequences, were determined based on sequence similarities to other turtles. The mitochondrial regulatory regions and flanking sequences of diverse freshwater turtle species were recovered using Long-PCR and gene-specific primers. To clarify the genetic links between the fresh water turtle species that share the same habitat type, a tree was created based on Cytochrome b sequencing data and the PCR- Restriction fragment length polymorphism (RFLP) pattern.

Keywords: Complex evolution, Phylogenetics, Phylogenomics, Tetrapod vertebrates