Litoleptis himukaensis 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

Litoleptis himukaensis Imada & Kato sp. n.

[Japanese name: himuka-shitone-abu] ( Figs. 3 g, 3h, 4d, 8)

Description. Body length: 2.8 mm (n=3) in male, 2.9 mm (n=2) in female. Wing length: 2.4 mm (n=4) in male, 2.6 mm (n=2) in female. Head Frons bare in both sexes. Antenna 0.53 mm (n=3). Antenna 1.0 times as long as diameter of eye. First flagellomere straight and gradually tapering towards apex; covered with comparatively rough and long setae ( Fig. 8 a). Male ( Fig. 8 b) Gonostylus with oblong-shaped extension apically; posterior surface of apex hollowed and weakly pointed inwardly; undulating in posterior edge of basal part. Sperm sac bulbous and hardly visible. Lateral ejaculatory process apparently not integrated into sperm sac, freely elongate transversely. Ejaculatory apodeme moderately long but not reaching anterior margin of gonocoxite. Posteromedial margin in ventral surface of gonocoxite bear less than four bristles. Aedeagus smoothly connected with paramere at thick and wide joint. Paramere slightly swollen posteriorly near distal end; become widest at connection with aedeagus, less than two times as wide as distal end.

Type material. Holotype. JAPAN [KYUSHU] 1♂, emerged 14. II 2009 from larvae collected by MK on 17.I.2009 at Udo Jingū, Miyazaki Pref, Japan ( Fig. 1 :9), “Rh 0195”, NMNS. Paratypes. 3♂, 3♀ (Rh 0196–0201), emerged 10–17.II.2009 from larvae collected by MK on 17.I.2009 at same locality as holotype ( Fig. 1 :9), KUHE.

Etymology. The specific epithet is taken from classical name of the type locality, “Himuka”, southern part of Miyazaki Prefecture.

Distribution. Japan (Honshu: Miyazaki Prefecture) ( Fig. 1 ).

Natural history. Habitat of this species is rocky slope along streams in coastal evergreen Castanopsis forests. Larvae of this species are thallus miner of Reboulia hemisphaerica ( Fig. 11 g). Adults emerged in spring (March- July, in laboratory condition).

Diagnosis. Litoleptis himukaensis resembles L. kiiensis and L. niyodoensis , and can be distinguished from them by the gonostylus with oblong-shaped extension apically (as opposed to L. kiiensis ), of which posterior surface of apex is hollowed (as opposed to flat at apex in L. niyodoensis ).

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 8. Litoleptis himukaensis sp. n. (a) Antenna of male in lateral view [Rh 0195], (b) male gonocoxite in dorsal (left) and ventral (right) view [Rh 0200]. Joint of gonocoxite and epandrium is circled and pointed by arrow. Scales = 0.1 mm.

FIGURE 11. Habits of Japanese Litoleptis. (a) Typical habitat of Litoleptis japonica sp. n. at Nanataki in Wakayama Pref., (b) adult female of L. japonica sp. n. at Kakuma-onsen in Nagano Pref., (c) cross section of a thallus of Conocephalum conicum, in which a larva of L. japonica sp. n. mined. (d) larva of Litoleptis japonica sp. n., (e) pupa of Litoleptis japonica sp. n. (white arrow), (f) larva of Litoleptis kiiensis sp. n., (g) mines of L. himukaensis (black arrows) (h) pupa of L. asterellaphile (white arrows).