New host and distributional records of the genus Stenichneumon Thomson, 1893 (Hymenoptera: Ichneumonidae), with key to species occurring in Japan

Abstract

Stenichneumon Thomson, 1893 comprises 23 species in the Holarctic, Oriental, and Neotropical regions. In Japan, five species, S. culpator iwatensis Uchida, 1926, S. militarius naironis Uchida, 1926, S. nigriorbitalis Uchida, 1930, S. odaiensis Uchida, 1932 and S. posticalis (Matsumura, 1912) have been recorded. Here, we report new host records, S. culpator iwatensis emerged from pupa of Autographa nigrisigna (Walker, 1858) and S. posticalis emerged from pupa of Ctenoplusia agnata (Staudinger, 1892). The latter host was collected as larva, and this is the first information on the host life stage attacked by this genus. New distributional records are S. nigriorbitalis from Shikoku and S. odaiensis from Hokkaido. In addition, we provided an identification key to Japanese species of the genus.