Exechia serrae 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 serrae Lindemann sp. n.

Materials

Type status: Holotype. Occurrence: catalogNumber: TSZD-JKJ-111561 ; recordedBy: A. Nakanishi; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location: country: Nepal; stateProvince: Gandaki Pradesh ; county: Myagdi District ; locality: Mudi , Dobang Kharka ; verbatimElevation: 2400 m; decimalLatitude: 28.6000; decimalLongitude: 83.4000; Event : eventDate: 1971-10-23; Record Level: institutionCode: KUEC

Description

Male: Body length 3.5 mm. Wing length 3.2 mm. Colouration (Dry specimen). Head, face and clypeus brown; labellum and palpus yellow. Antenna with scape and pedicel yellow; flagellum brown. Scutum and lateral sclerites pale brown; propleura yellow; halteres whitish-yellow. Legs whitish-yellow. Abdomen dark brown, tergites II-III with a lateral pale area. Terminalia yellow. Head. Frons and vertex covered with short pale setae. Clypeus covered with pale setae. Antenna 2 times as long as length from vertex to ventral margin of clypeus; flagellomeres longer than broad, with sixth flagellomere 1.4 times as long as wide. Thorax. Scutum covered with short, pale setae. Legs. Fore leg with tibia 0.78 times as long as first tarsomere. Mid-tibia with 18 anterior, 4 posterodorsal, 10 posterior and 4 posteroventral bristles. Hind tibia with 8 anterodorsal, 3 posterodorsal and 4 posterior bristles. Wings. Vein r-m 3.7 times longer than stem of M-fork. Abdomen. Tergites covered with pale setae. Terminalia (Fig. 35). Each part of divided tergite IX apically with about 3 setae, 2 most apical setae stout. GL (Fig. 35 a, b) with entire length covered with setae; apex with 2 setae. Aedaegal guides elongate and spathulate (Fig. 35 a). Hypandrium (Fig. 35 a, b) strongly extended distally, forming large lobe that reaches far beyond apicoventral gonocoxal margin; covered with about 12 setae, with apical pair stout and reaching far beyond the level of the GL apex. Hypandrial lobe with each branch elongate, narrow, evenly tapered, apex acute (Fig. 35 a). Gonostylus (Fig. 35 c) with DB forming slender distally projecting baso-external lobe; basal part squared, abruptly tapered distally, apical part slender elongate, apex somewhat spathulate; basodorsal part evenly covered with setae; baso-external lobe with 2 apical setae, one on apex. VB small, apex rounded, with 3 setae, 2 most apical setae close to apex. IB with apical half slender, apex forming hyaline membranous area; apically with 1 seta close to apex and row of 3 setae on shelf one-third from apex. MB large, elongate; internal margin with few large teeth; apically hollowed with small seta within hollow area close to apex.

Female: Unknown.

Diagnosis

Distinguished from E. columna in having the gonocoxal lobes not reaching beyond the apical hypandrial setae (Fig. 35 a, b) and the medial gonostylus branch with internal margin forming several large teeth (Fig. 35 c); from other species in the E. parva group by the hypandrium forming a distally-extended lobe that reaches far beyond apicoventral gonocoxal margin (Fig. 35 a, b) and the dorsal gonostylus branch forming a baso-external lobe with two apical setae (Fig. 35 c).

Etymology

From Latin serra, saw, relating to the shape of the medial lobe of the gonostylus.

Distribution

Oriental, Nepal (Fig. 19 ).

Biology

Adult collected in the eastern Himalayas (2500 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).