Exechia bifasciata Lindemann, 2021

Lindemann, Jon Peder, Soli, Geir & Kjaerandsen, Jostein, 2021, Revision of the Exechia parva group (Diptera: Mycetophilidae), Biodiversity Data Journal 9, pp. 67134-67134 : 67134

Exechia bifasciata Lindemann sp. n.

Materials

Type status: Holotype. Occurrence: catalogNumber: TSZD-JKJ-111548 ; recordedBy: T. Saigusa; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location: island: Kyushu ; country: Japan; stateProvince: Miyazaki prefecture; locality: Kobayashi-shi , Inokodanibashi 2-5 ; verbatimElevation: 365-450 m; Event : eventDate: 2004-04-17; Record Level: collectionCode: KUEC

Description

Male: Body length 3.7 mm. Wing length 3.2 mm. Colouration (Dry specimen). Head, face and clypeus dark brown; labellum brown; palpus dark brown. Antenna with scape and pedicel yellow; flagellum dark brown, basal half of first flagellomere pale. Scutum and lateral sclerites dark brown; propleura brown; halteres whitish-yellow. Wings hyaline with two weak dark marks, one reaching from apical part of costal cell to middle of cell r4+5 and the other covering area posterior to cubital fork (Fig. 9 e). Legs yellow. Abdomen dark brown. Terminalia pale brown. Head. Frons and vertex covered with pale setae. Clypeus densely covered with pale setae; flagellomeres quadrate, with sixth flagellomere as long as broad. Thorax. Scutum covered with short pale setae. Legs. Fore leg with tibia length 0.93 times length of first tarsomere. Mid-tibia with 21 anterior, 5 posterodorsal, 8 posterior and 6 posteroventral bristles. Hind tibia with 11 anterodorsal, 4 posterodorsal and 5 posterior bristles. Wings (Fig. 9 e). Vein r-m 2 times longer than stem of M-fork. Abdomen. Tergites covered with short, pale setae. Terminalia (Fig. 9). Each part of divided tergite IX apically with about 20 setae, most apical setae stout. Each cercus triangular with apex truncate and base acute (Fig. 9 d). Gonocoxites evenly covered with setae on apicoventral half (Fig. 9 a, b). GL very short, length about 0.17 of gonocoxite width, entirely covered with setae, apex with 3 short setae (Fig. 9 a, b). Aedaegal guides elongate, curved interiorly, basal part wide, abruptly tapered, apical two-thirds slender, apex rounded (Fig. 9 a, b). Hypandrium covered with about 13 setae with apical pair reaching slightly beyond level of GL apex (Fig. 9 a, b). Hypandrial lobe with each branch lanceolate, apically rounded (Fig. 9 a). Gonostylus (Fig. 9 c) with DB large, wide, spathulate, apical half almost as broad as basal half, dorsal side with baso-internal part densly covered with setae, baso-external margin with three small setae. VB ovate, apex rounded, 2 setae close to apex. IB with apex expanded into round membranous area, apically with 1 seta located slightly below apex, pair of setae located one-third from apex. MB large, wide, almost as long as DB, geniculate, apically with 2 very small setae close to apex, medio-internally with 1 seta.

Female: Unknown.

Diagnosis

Distinguished from all species in the E. parva group in having the wings with dark marks (Fig. 9 e), the gonocoxal lobes very short with length only about 0.17 of gonocoxite width (Fig. 9 a), each cercus triangular and apically truncate (Fig. 9 d), the aedaegal guides very distinctive (Fig. 9 a, b) and by the shape of the dorsal and medial branch of the gonostylus (Fig. 9 c).

Etymology

From Latin fascia, band, with the Latin prefix bi -, two, relating to the specific wing pattern, forming two dark bands.

Distribution

East Palaearctic, Japan (Fig. 10 ).

Biology

Unknown.

Figures

Figure 10. Distribution map of species in the E. parva group occurring in the East Palaearctic Region, based on localities from studied material, type material and DNA-barcoded material. Different species are represented by individual colours. Altitudes are indicated in shades from grey (lowland) to white (mountains).