Sexual behavior of Leseha vespa Smith & Nishida, 2019 (Hymenoptera, Tenthredinidae, Selandriinae)

ABSTRACT: Small swarms of male Leseha vespa Smith & Nishida, 2019 flew during the morning hours searching for the much less abundant females on the upper surfaces of protruding leaves of various plant species at a site where a large population of the host fern Phlebodium pseudoaureum had been recently decimated (probably by L. vespa larvae). Males showed no sign of aggressive behavior toward other males, and only poor abilities to locate females resting on leaves. Although >100 male-female interactions were observed, they seldom led to copulation, as females were generally unreceptive. The males probably used visual cues to choose leaves, but the short-range cues that they used to encounter females there were not clear. Individually marked males returned to the same site for up to 11 days.