First Records of the Blacktail Triplefin (Perciformes: Tripterygiidae), Helcogramma aquila, from Japan, with Notes on its Fresh Coloration

抄録

Eight specimens (33.2-40.8 mm standard length) of Helcogramma aquila Williams and McCormick, 1990 (Tripterygiidae), previously known from the Philippines and the Mariana Islands, were collected from Okinoerabu-jima and Okinawajima islands in the Ryukyu Islands, Japan. These specimens represent the first records of this species from Japan, and the specimen from Okinoerabu-jima island is the northernmost record for the species. Underwater photographs of male and female individuals and color photographs of a fresh male specimen are given for the first time for H. aquila.