ITS Ribosomal DNA Distinctions and the Genetic Structures of Populations of Two Sympatric Species of Pavona (Cnidaria: Scleractinia) from Mauritius

Abstract

In this study, we examined the genetic differences between Pavona cactus and P. decussata, two of the major components of the shallow reef flat coral communities in Mauritius, which not only occur in sympatry but are often intricately associated. Using sequences of ribosomal internal transcribed spacers (ITSs), we conducted phylogenetic, population, and nested clade analyses (NCA) on both species sampled from Bambous Virieux on the southeastern coast and Trou aux Biches on the northwestern coast of the island. The phylogenetic analysis of ITS sequence types supported the distinct species status of P. cactus and P. decussata. The significant difference detected by the NCA indicated that both P. cactus and P. decussata in Mauritius constitute statistically distinguishable lineages. No population structure was detected between the two geographic locations. We conclude that P. cactus and P. decussata remain distinct evolutionary units despite their ecological uniqueness in Mauritius.