Phenacoscorpius longicaudalis , a new species of scorpionfish (Teleostei: Scorpaenidae) from Western Australia, with first records of Phenacoscorpius adenensis from the southeastern Indian Ocean

Phenacoscorpius longicaudalis sp. nov. is described from 19 specimens collected in depths of 228–990 m off Western Australia, eastern Indian Ocean. The new species is distinguished from other congeners by the following combination of characters: pectoral-fin rays 17–19 (mode 18), middle rays branched; palatine teeth absent; second preopercular spine small; lateral lacrimal spine usually absent; head width 14.7–16.9 (mean 15.4) % of SL; snout length 9.9–11.0 (10.5) % of SL; orbit diameter 13.4–16.1 (15.1) % of SL; caudal-fin length 25.6–29.5 (27.6) % of SL; and caudal-peduncle length 19.1–23.8 (20.6) % of SL. In addition, five specimens of the Indo-West Pacific species Phenacoscorpius adenensis , also collected off Western Australia, are described, the specimens representing the first records of the species from the southeastern Indian Ocean.