Two New Species of Pseudojuloides from Western Australia and Southern Japan, with a Redescription of Pseudojuloides elongatus (Teleostei: Labridae)

Abstract

The anti-equatorial labrid Pseudojuloides elongatus has a wide but disjunct distribution across the Western Pacific and Eastern Indian Oceans, with populations occurring in Western Australia, southern Japan, and the southwest Pacific Ocean. Principal component analysis of morphological characters and coalescent-based species-tree estimates of mitochondrial and nuclear DNA markers suggest that these populations are under incipient stages of divergence. The three allopatric populations differ strongly in coloration patterns of both sexes, particularly in terminal males, suggestive of reproductive isolation. We redescribe Pseudojuloides elongatus on the basis of nine paratypes and two additional specimens from eastern Australia and Norfolk Island, and describe two new species, Pseudojuloides crux, new species, from Western Australia, and P. paradiseus, new species, from southern Japan. The complex is distinguished from other members of the genus in sharing the following combination of characters: body elongate; dorsal-fin rays IX,12; pectoral-fin rays 12; no median predorsal scales; and usually 27 lateral-line scales. We briefly comment on anti-equatorial biogeographical patterns and Pseudojuloides argyreogaster from the Western Indian Ocean.