Exechia chirotheca 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 chirotheca Lindemann sp. n.

Materials

Type status: Holotype. Occurrence: catalogNumber: TSZD-JKJ-111552 ; recordedBy: J. Emoto; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned , with genitalia in glycerine in separate microvial; Location : country: Nepal; stateProvince: Province No. 1; county: Terhathum District ; locality: Basantapur ; verbatimElevation: 2300 m; decimalLatitude: 27.1333; decimalLongitude: 87.4333; Event: eventDate: 1972-05-06; Record Level: institutionCode: KUEC

Description

Male: Body length 3.3 mm. Wing length 2.8 mm. Colouration (Dry specimen). Head, face dark and clypeus dark brown; labellum pale brown; palpus yellow. Antenna with scape and pedicel yellow; flagellum brown, basal half of first flagellomere pale. Scutum, lateral sclerites and propleura brown; halteres yellow. Legs yellow. Abdomen dark brown. Terminalia yellow. Head. Frons and vertex covered with pale setae. Clypeus covered with pale setae, evenly distributed. Antenna long, 2.2 times as long as length from vertex to ventral margin of clypeus; flagellomeres longer than broad, with sixth flagellomere 1.5 as long as wide. Thorax. Scutum covered with pale setae. Legs. Fore leg with tibia 0.83 times as long as first tarsomere. Mid-tibia with 21 anterior, 3 posterodorsal, 10 posterior and 3 posteroventral bristles. Hind tibia with 9 anterodorsal, 4 posterodorsal and 6 posterior bristles. Wings. Vein r-m 2.9 times longer than stem of M-fork. Abdomen. Tergites covered with short, pale setae. Terminalia (Fig. 18). Each part of divided tergite IX apically with about 6 setae, the 2-3 most apical setae stout. Gonocoxites evenly covered with setae, except on basoventral half (Fig. 18 a, b); GL apex with 3 stout short setae (Fig. 18 a, b). Aedaegal guides elongate with parallel margins, apex acute (Fig. 18 a, b). Hypandrium with about 6 setae, apical pair relatively short, reaching about the GL basal fourth (Fig. 18 a, b). Hypandrial lobe with each branch basally wide, apically narrow, evenly tapered (Fig. 18 a). Gonostylus (Fig. 18 c) with DB large, elongate, apex rounded, apicoexternal margin forming a short rounded lobe extending distally; dorsal side evenly covered with setae. VB apically acuminate, apex acute, with 2 setae, most apical seta on apex. IB apically with 1 seta on apex and pair of setae on elevated area one-third from apex. MB short, slightly curved interiorly towards acute apex; apically forming a small finger-like process, with 2 setae on the apex.

Diagnosis

Distinguished from all species in the E. parva group in having the medial gonostylus branch with an apical finger-like process with 2 setae at the apex (Fig. 18 c), the gonocoxal lobe apex with relatively short and stout setae (Fig. 18 a, b) and by the shape of the dorsal gonostylus branch (Fig. 18 c).

Etymology

From Latin chirotheca, mitten, relating to the shape of the dorsal and medial lobes of the gonostylus, resembling mittens.

Distribution

Oriental, Nepal (Fig. 19 ).

Biology

Adult collected in the eastern Himalayas (2300 m a.s.l.).

Figures

Figure 19. Distribution map of species in the E. parva group occurring in the eastern Himalayas (Oriental 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).