Phylogenetic Relationships in the Coral Family Acroporidae, Reassessed by Inference from Mitochondrial Genes

Abstract

Phylogenetic relationships within the dominant reef coral family Acroporidaewere inferred from the mitochondrial genes cytochrome b and ATPase6. The rate of nucleotide substitution in the genes gave proper resolutionto deduce genetic relationships between the genera in this family.The molecular phylogeny divided this family into three major lineages:the genera Astreopora, Montipora and Acropora. The genus Anacroporawas included in the same clade as the genus Montipora, suggestingits recent speciation from Montipora. The subgenus Isopora was significantlydistant from the subgenus Acropora. Taken together with morphologicaland reproductive differences, we propose that these two subgenerabe classified as independent genera. The divergence times deducedfrom the genetic distances were consistent with the fossil recordfor the major genera. The results also suggest that the extant reefcorals speciated and expanded very recently, probably after the Miocene,from single lineage which survived repeated extinction by climatechanges during the Cenozoic era.