Psilotreta voluta Kawase 2021

(Figs 6A–6F, 10B–10C, 11D)

Psilotreta voluta Kawase 2021, 590–593, male, female, Honshu, Shikoku (Type locality: Kochi), Yakushima Island and Fukue Island.

Remarks. The male and female of this species are most similar to those of P. atrocaudata sp. nov. but can be distinguished by characters given in the diagnosis for P. atrocaudata sp. nov. The larva collected from Fukue Island near Kyushu and associated with the male of this species cannot be distinguished from the larva of P. spatulata sp. nov. described above. Some larval specimens that are identical to those of P. voluta or P. spatulata sp. nov. were found also widely over much of Kyushu Island (Kawase unpublished) but the association of those larvae and adults needs to be confirmed.

Specimens examined. Fukue Island: 1 larva, Goto-shi, Tomie-machi, Shigejiki, Nagasaki, 32°39'N, 128°45'E, 28.viii.2018, N. Shimura; 1 male, 2 females, larvae collected from same locality on same date, adults emerged from iii.2019 to 16.v.2020 by N. Shimura.

Distribution and habitat. Psilotreta voluta is an East Palearctic species distributed in western Honshu, Shikoku, Fukue Island and Yakushima Island (Fig. 11D, arrows). Adults were collected near mountainous streams at light in Honshu, Shikoku and Yakushima Island. Larvae were found in small streams of Fukue Island.

Japanese name. Uzu-kiso-tobikera.