Patterns of lineage diversification in the genus Naso (Acanthuridae)

摘要: The evolutionary history of the reef fish genus Naso (F. Acanthuridae) was examined using a complete species-level molecular phylogeny all recognized (19) species based on three loci (one nuclear ETS2 and two mitochondrial 16S, cyt b). This study demonstrates that distinct foraging modes specialized body shapes arose independently at different times in genus. Members subgenus Axinurus, characterized by scombriform morphology, caudal fin structure pelagic mode, were consistently placed basal to remaining species, suggesting is plesiomorphic benthic derived this We used genus-level (nuclear marker, ETS2), which included several taxa from other acanthurid genera, obtain range age estimates for most recent common ancestor Naso. These (range 52-43.3 MY) then estimate divergence (by nonparametric rate smoothing method) node giving rise extant combined sequence data (from loci). reconstruction pattern indicates sequences events. during Eocene Oligocene. Most including those foraging, over period 20 MY Miocene. Diversification associated with major plate tectonic glaciation events, resulting changes sea level, ocean temperature productivity regimes. Regardless mode exhibited, have propulsive unit similar observed fishes, legacy position Axinurus