Revision of the genus 'Microbrotula' (Teleostei: Bythitidae), with description of two new species and a related new genus

Following recent systematic revisions of Anderson (2005, 2007), seven species of the viviparous genus Microbrotula (Teleostei: Bythitidae) have been described, all from the Indo-west Pacific Ocean. Six of these species are here recognised as valid: M. bentleyi, M. greenfieldi, M. punicea, M. queenslandica, M. randalli and M. rubra. Microbrotula polyactis is regarded as a junior synonym of M. bentleyi. Two additional new species, M. andersoni and M. hamata, obtained from Christmas Island (eastern Indian Ocean) and New Caledonia, respectively, are described herein. The main specific characters distinguishing the new species are the number of precaudal vertebrae, numbers of pectoral, caudal and dorsal fin rays, number and distribution of head pores, number and distribution of sensory papillae on the head and lateral line, presence or absence of a (mostly hidden) curved spine at the lower angle of the preopercle, and otolith morphology. The limits of the genus Microbrotula are redefined and the genus is compared with other shallow water bythitine genera. Calamopteryx is regarded as the genus that is most closely related to Microbrotula. As a result of the redefinition of Microbrotula, one of its previously assigned species, M. randalli, is placed in a new genus, Ematops, characterised by the head pore pattern, unique presence of scales partly covering the eye, number of precaudal vertebrae, number of pectoral and caudal fin rays and the otolith proportion.