A new species of Gemmula, Weinkauff 1875; Evidence of two clades of Philippine species in the genus Gemmula

Abstract

A new species of Philippine turrid, Gemmula ambara (the amber gem turrid), is described. The type locality is Balicasag Island, Bohol, Phlippines; the holotype and several paratypes were collected at the type locality using tangle nets at depths of 70-120 fathoms. The species occurs offshore across a number of central Philippines localities; it has also been collected off Panglao Island using tangle nets and off Aliguay Island using small trawls. Gemmula ambara had been mistakenly regarded by collectors and dealers as a small variety of Gemmula diomedea, but a more careful examination of the shell morphology easily separates the two species. A preliminary analysis of the phylogeny of Gemmula ambara using standard molecular markers has revealed that in fact, this species is not closely related to Gemmula diomedea but instead, is more closely related to Gemmula rosario and Gemmula lisajoni. It appears that the species of Gemmula from the Philippines can be divided into two distinct branches, with Gemmula ambara, Gemmula rosario and Gemmula lisajoni comprising one branch, and Gemmula diomedea, Gemmula speciosa, Gemmula kieneri, and Gemmula sogodensis comprising a second branch.