Description of a new Luidia species (Asteroidea: Paxillosida: Luidiidae) from Japan with molecular phylogenetic analysis of the genus Luidia

Luidia iwakiensis n. sp. (Asteroidea, Echinodermata) is described in Japanese waters. A molecular phylogenetic analysis including 18 Luidia species supported Döderlein L (1920, Siboga Expedition 4, 193–291) four morphogroups. Morphological reconsideration revealed three of the eight criteria of the morphogroup adopted by Döderlein were justified, but the remaining five characters were rejected. The placement of the new species in the Ciliaris-group was supported by molecular as well as morphological evidence, however, it varies from other species of Ciliaris-group by arm number, length of major inferomarginal spines, and pedicellariae on actinal plates.