New Record of a Marine Fish Parasite <i>Nerocila trichiura</i> (Crustacea: Isopoda: Cymothoidae) from Japan, with its Confirmed Distribution in the Western North Pacific Ocean

Abstract

The cymothoid isopod Nerocila trichiura (Miers, 1877) is reported based on an ovigerous female from the ventral body surface of a flyingfish, Cypselurus hiraii Abe, 1953 (Beloniformes: Exocoetidae), in the coastal Pacific waters of central Japan. This represents the first record of N. trichiura from Japan, and C. hiraii is a new host record for this isopod. Nerocila trichiura has been reported from the tropical and middle-latitude waters of the Indian and Atlantic oceans and was recorded in 1881 from the Philippines. This paper confirms that the species occurs in the western North Pacific Ocean.

<i>Nerocila phaiopleura</i> (Isopoda: Cymothoidae): a new record from Ibaraki Prefecture, central Japan, with a discussion of its distribution in Japanese waters

“…Isopods of the cymothoid genus Nerocila are skin parasites of marine fishes (Bruce, 1987). Currently, three nominal species of the genus are known from Japan: Nerocila phaiopleura Bleeker, 1857 (see Nagasawa & Isozaki, 2017), N. japonica Schioedte & Meinert, 1881 (Yamauchi & Nagasawa, 2012;Nagasawa & Tawa, 2019), and N. trichiura (Miers, 1877) (Nagasawa & Isozaki, 2019). In 1982, N. phaiopleura was reported for the first time from Japan (Mitani, 1982), where the species has since been recorded from nine species of coastal wild fishes (3 species from the Clupeidae, 1 species from the Dussumieriidae, 1 species from the Engraulidae, 1 species from the Carangidae, 2 species from the Scombridae, 1 species from the Sphyraenidae: Nagasawa & Isozaki, 2017) and from farmed Pacific bluefin tuna, Thunnus orientalis (Temminck & Schlegel, 1844) (Scombridae) (Nagasawa & Shirakashi, 2017).…”