Trichosia (Trichosia) stylofornix, Sutou & Menzel, 2025

Trichosia (Trichosia) stylofornix sp. nov.

Fig. 3 A ‒ D View Figure 3

Type material.

Holotype. JAPAN • ♂; Kyushu, Kumamoto Pref., Aso, Aso National Park , coniferous plantation of Cryptomeria japonica ; 32°55'N, 131°06'E; alt. 700 m; 12–14 Oct. 1995; M. Jaschhof leg., aspirator and sweep-net; SDEI GoogleMaps . Paratypes. JAPAN • 29 ♂♂; same data as for holotype; 23 ♂♂, SDEI; 2 ♂♂, NSMT; 2 ♂♂, PCMS; 2 ♂♂, MZH GoogleMaps • 2 ♂♂; Honshu, Tokyo, Miyake Island, Hinoyama-touge ; 34°06'N, 139°33'E; 5–7 Apr. 2010; J. Aoki leg., flight interception trap; SDEI GoogleMaps .

Description.

Male. Head: Eye bridge 2‒3 facets wide. Prefrons with about 5 setae and clypeus bare or with a seta. Scape brown with about 5 setae anteriorly, pedicel brown with about 10 setae; flagellomeres brown, base of 1 st flagellomere yellow; 4 th flagellomere about 5.0 times as long as wide, neck portion about 1 / 8 of its whole length (Fig. 3 A View Figure 3 ), hairs yellowish brown and longer than width of flagellomere. Palpus yellowish brown, 3 - segmented with length ratio 1.8: 1.0: 2.1, 1 st segment with 1‒3 (mostly 2) setae on its outside and with indistinct sensory area bearing minute sensilla, 2 nd segment with 6‒7 setae, frequently one of them distinctly longer than the others, 3 rd segment slender with about 10 setae (Fig. 3 B View Figure 3 ). Thorax: Color predominantly brown; mesonotum with both short and long setae; scutellum with at most 4 long setae and some short setae; posterior pronotum bare. Coxae, femora, and tibiae predominantly yellowish brown, tarsi brown; tibiae and basitarsi, especially hindtibia with differentiated spine-like short setae in ground setosity; fore tibial spur about 1.2 times as long as width of tibial apex. Wing with brownish anterior veins and light brownish posterior veins; wing membrane bare; distal 1 / 5‒1 / 4 of R 5 with both dorsal and ventral macrotrichia, bM, r-m, M 1, M 2, CuA 1, and CuA 2 with dorsal macrotrichia, stem of M bare or with several dorsal macrotrichia; length of R 1 = 0.6‒0.7 R, c = 0.7‒ 0.8w, r-m = 0.5‒1.0 bM, stem of CuA = 0.3‒0.7 bM; R 1 ending slightly before branching point of M 1 and M 2; wing length 1.8‒2.4 mm. Halter yellowish brown, knob and distal 1 / 4‒1 / 3 of stalk with setae. Abdomen: Tergites and sternites brown with brownish setae, membrane between tergites and sternites yellowish brown. Gonocoxite wider than long (Fig. 3 C View Figure 3 ); gonostylus longer than wide with apical spines, and inside of dorsal surface with arcuate concavity where 3‒5 spines are present, 2 of them arranged parallel (Fig. 3 D View Figure 3 ); tegmen membranous, wider than long with weakly sclerotized base (Fig. 3 C View Figure 3 ); aedeagus nearly V-shaped (Fig. 3 C View Figure 3 ). Body size: 1.9‒2.9 mm.

Female. Unknown.

Remarks.

This new species is distinctive in having long antennal flagellomeres (Fig. 3 A View Figure 3 ). It also has unique structures of the gonostylus (Fig. 3 D View Figure 3 ), and is named after the characteristic arcuate concavity of dorsal surface of the gonostylus (‘ fornix ’ means arch in Latin). The distribution of this species is so far restricted to Kumamoto, southwestern Japan, and Miyake Island, 175 km south of Tokyo metropolis.