Meeting Abstract
Tropical Indo-Pacific aeolidid nudibranchs of the family Fionidae are poorly known. Many undescribed species are found throughout the Indian and Pacific Oceans and are concentrated in the “Coral Triangle”, which includes the Philippines, Papua New Guinea, Indonesia, and Malaysia. It has the highest concentration of marine biodiversity for most groups of organisms. With recent publication of revised systematics of the Fionidae, description of new taxa of Fionidae is especially warranted. Interestingly, one particular species, Tenellia yamasui Hamatani, 1993, has been repeatedly misidentified. In this project, the phylogenetic placement of Tenellia yamasui, Tenellia n. sp. 1, Tenellia n. sp. 2, Tenellia sp. 3, Abronica sp. 1 and Abronica sp. 2 from the waters inside the Coral Triangle was investigated. Both morphology and molecular data were used to analyze species. SEM photographs of the radula, jaws, and reproductive system were employed to characterize the taxa. DNA was extracted from the foot of the nudibranchs and PCR amplicons were sequenced for mitochondrial 16S, COI and nuclear H3 genes. The newly acquired data were used to complement already existing data in a new, comprehensive phylogenetic analysis. This analysis corroborates the distinctiveness of Tenellia yamasui from Tenellia sp. 1 and T. sp. 2, with strong support and that these three are each other’s closest relatives. This study also confirms that all four species of Abronica are characterized by having an acutely-pointed curved penial stylet, thus confirming a unique morphological synapomorphy for members of this genus. It also confirms that Tenellia sp. 3 is closely related to coral-eating species of Tenellia.