Pseudojuloides cerasinus
Pseudojuloides cerasinus, the smalltail wrasse or the pencil wrasse, is a species of marine ray-finned fish, a wrasse from the family Labridae. It is found in the tropical Pacific Ocean and was previously considered to have a much wider distribution but the recognition of new species has reduced this wide range. Description. "Pseudojuloides cerasinus" in their male or terminal phase has a distinctive blue mid-lateral stripe which is situated immediately above a yellow stripe and the posterior portion of the caudal fin is black, edged with blue. In these males the body is an overall green  colour and they have a single blue facial stripe. Some males show black spots on the membranes between the first two spines on the dorsal fin. Females of all species in the genus "Pseudojuloides" tend to be orange or reddish in colour. This is a small species which grows to a total length of . Distribution. "Pseudojuloides cerasinus" is known only from the seas around Hawaii. Habitat and biology. "Pseudojuloides cerasinus" is frequently recorded in clear lagoon and near seaward reefs over coral rubble substrates, it is infrequently recorded over live coral and clumps of algae. It inhabits depths of around  , although it is more common at depths in excess of . Taxonomy. "Pseudojuloides cerasinus" was formerly regarded as having a wide Indo-Pacific distribution but the taxon "P. cerasinus" "sensu lato" is now widely regarded as a species complex and "P. cerasinus" "sensu stricto" is now thought to be endemic to Hawaii. The three Indian Ocean species "P. xanthomos" from Mauritius, "P. polackorum" from South Africa to Madagascar and "P. kaleidos" of the Maldives to the Greater Sundas were the first to be recognised while "P. splendens" from the western Pacific Ocean and "P. polynesica" of Polynesia were recognised more recently . "Pseudojuloides cerasinus" was originally described as "Pseudojulis cerasina" in 1904 by the American ichthyologist John Otterbein Snyder (1867-1943) with the type locality given as Honolulu. When Henry Weed Fowler described the genus "Pseudojuloides" he designated "Pseudojulis cerasina" as the type species of the new genus.