Meeting Abstract
Nudibranchs offer a fascinating system to investigate biogeography and color evolution due to their ranges and mesmerizing pigmentation. The overall lack of a fossil record requires the use of morphological and molecular data to piece together this group’s enigmatic history. The family Tritoniidae (Nudibranchia: Cladobranchia: Dendronotidae) is often cryptic on their octocoral prey, brilliantly mimicking their shape and color. The family has a murky evolutionary history; limited morphological and molecular work has been previously performed to resolve these relationships. This study examines the phylogeny of the two largest genera, Marionia and Tritonia, by the concatenation of four gene fragments (16S+28S+COI+H3). Maximum likelihood and Bayesian inference analyses shed new light onto the evolutionary relationships of these groups and an ancestral area reconstruction provides insight into biogeographic origins. Marionia and Tritonia are returned as well-supported, monophyletic groups with ancestral origins in the Indo-Pacific. The importance of color is reiterated in Marionia, which is divided into three clades defined by striping pattern, spots, and translucence. The discovery of these well-supported clades and biogeographic origins stresses the importance of color in nudibranchs and the breadth of biodiversity found in the Indo-Pacific.
