Description of two species of the genus Astrodia Verrill, 1899 (Ophiuroidea, Euryalida, Asteronychidae), including a new species from seamounts in the West Pacific

Morphological characters of paratypes of Astrodia duospina sp. nov. A arm spines of RSIO31004 B arm spines of RSIO61069 C–E pictures of RSIO59012, oral disc (C), aboral disc (D), arm and arm spines (E) F aboral disc of RSIO31004. These specimens have exceptionally three arm spines for an arm segment (shown by an arc in A and B). Abbreviations: AS arm spine; T teeth; PO plate-shaped ossicle; GS genital slit; G gonad; RS radial shield. Scale bars: 2 mm (F); 1 mm (C, E); 0.5 mm (A, B, D).