Litoleptis izuensis Imada & Kato

Imada, Yume & Kato, Makoto, 2016, Bryophyte-feeding of Litoleptis (Diptera: Rhagionidae) with descriptions of new species from Japan, Zootaxa 4097 (1), pp. 41-58 : 50-51

Litoleptis izuensis Imada & Kato sp. n.

[Japanese name: izu-jingasa-shitone-abu] ( Figs. 3 i, 4e, 9)

Description. Body length: 3.4 mm (n=2) in male. Wing length: 4.3 mm (n=2) in male. Head Frons bare in male, with sparse hairs in female. Antenna 0.32 mm (n=2). Antenna 1.1 times as long as diameter of eyes. First flagellomere straight and gradually tapering towards apex, slightly bulbous dorsally near apex; densely covered with comparatively long hairs ( Fig. 9 a). Male ( Fig. 9 b) Gonostylus with triangle-shaped extension posteriorly, tapering toward apex, widest point at base twice as wide as apex. Sperm sac posteriorly cylindrical in internal aedeagual process, and widen and forked toward anterior end. Lateral ejaculatory process small and round-shaped without elongation, weakly sclerotized. Ejaculatory apodeme short, posterior end broad and tapering toward anterior margin of gonocoxite. Posteromedial margin in ventral surface of gonocoxite bear less than four bristles. Aedeagus tapering toward apex; smoothly connected with paramere. Paramere consistently slender, approximately six times as narrow as width of gonostylus at basal widest point. Female. Unknown.

Type material. Holotype. JAPAN [HONSHU] 1♂, holotype, emerged on 7.IV.2009 from larva collected by MK on 22.III.2009 at Izu Oshima, Tokyo Metropolitan, Japan ( Fig. 1 :23), “Rh 0202”, NMNS.

Paratype. 1♂ (Rh 0203), emerged on 2.IV.2009 from larva collected by MK on 22.III.2009 at same locality as holotype ( Fig. 1 :23), KUHE.

Etymology. The specific epithet is a noun in apposition, taken from the Izu Oshima Island where this species was found.

Distribution. Japan (Honshu: Tokyo Metropolitan) ( Fig. 1 ).

Natural history. Habitat of this species is shaded clayey slope along streams and roads in evergreen Castanopsis forests. Larvae of this species are thallus miners of Reboulia hemisphaerica . Adults emerged in spring (April, in laboratory condition).

Diagnosis. Litoleptis izuensis can be distinguished from the congeners by the following characters: gonostylus greatly wide at base with triangle-shaped extension posteriorly, tapering toward apex, widest point at base twice as wide as apex; paramere narrow, approximately six times as narrow as width of gonostylus at basal widest point; lateral ejaculatory process small and round-shaped without elongation; sperm sac developed and forked at anterior end.

Figures

FIGURE 1. Map showing the sampling localities. Locality numbers correspond to those in the text.

FIGURE 3. Habitus of adults of Japanese Litoleptis species. L. japonica sp. n. (♂: a [holotype], ♀: b [Rh 0017]), L. kiiensis sp. n. (♂: c [Rh 0221], ♀: d [Rh 0114]), L. niyodoensis sp. n. (♂: e [holotype], ♀: f [Rh 0186]), L. himukaensis sp. n. (♂: g [Rh 0201], ♀: h [Rh 0196]), L. izuensis sp. n. (♂: i [holotype]), L. asterellaphile sp. n. (♂: j [Rh 0207], ♀: k [Rh 0206]). Scales = 0.1 mm.

FIGURE 9. Litoleptis izuensis sp. n. (a) Antenna of male in lateral view [holotype], (b) male gonocoxite in dorsal (left) and ventral (right) view [holotype]. Joint of gonocoxite and epandrium is circled and pointed by arrow. Scales = 0.1 mm. Abbreviation: ltr ejc prc, lateral ejaculatory process.