Exechia arcuata 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 arcuata Lindemann sp. n.

Materials

Type status: Holotype. Occurrence: catalogNumber: TSZD-JKJ-107175 ; recordedBy: J. Kjærandsen; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location: country: Kenya; stateProvince: Nyeri county; locality: Mt. Kenya , Northern Naro Moru , Base camp at Naro Moru River Lodge ; verbatimElevation: 3050 m; decimalLatitude: -0.17028; decimalLongitude: 37.215; Event : samplingProtocol: sweep net; eventDate: 2008-08-19; habitat: bamboo forest; Record Level: institutionCode: TMU

Description

Male: Wing length 3.2 mm. Colouration (Dry specimen). Head dark brown; face and clypeus brown; labellum and palpus yellow. Antenna with scape and pedicel yellow; flagellum brown, first flagellomere with yellow base. Thorax with scutum brown, lateral margin broadly yellow; lateral sclerites pale brown; propleura yellow; halteres whitish-yellow. Legs whitish-yellow. Abdomen dark brown, tergites II-III with lateral yellow area. Terminalia. Head. Frons and vertex covered with pale setae. Clypeus covered with pale brown setae. Antenna long, 2.3 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 pale setae. Legs. Fore leg with tibia 0.93 times as long as first tarsomere. Mid-tibia with 20 anterior, 4 posterodorsal, 8 posterior and 4 posteroventral bristles. Wings. Vein r-m 3 times longer than stem of M-fork. Abdomen. Tergites covered with pale brown setae. Terminalia (Fig. 7). Each part of divided tergite IX apically with about 7 setae, apical seta stout. Gonocoxites evenly covered with setae on apicoventral half (Fig. 7 a, b). Gonocoxal apicoventral margin, between GL and hypandrium, forming distinct protrusion with 2-3 elongate setae reaching far beyond GL apex (Fig. 7 a, b). Each GL small and distinctly curved interiorly, apex with row of 4 short setae somewhat extended down exterior margin (Fig. 7 a, b). Aedaegal guides indistinct or reduced. Hypandrium covered with about 6 setae, apical pair elongate, reaching far beyond GL apex (Fig. 7 a, b). Hypandrial lobe broad, apically tapering towards rounded apex (Fig. 7 a). Gonostylus (Fig. 7 c) with DB elongate, about 4 times longer than broad, apex distinctly spathulate; evenly covered with setae on dorsal side, except on apical fourth. VB ovate, apically acute, with 2 setae, apical seta on apex. IB with apex membranous rounded, apical part with row of 3 setae, apical seta close to apex. MB forming small apicointernal extension bearing 2 small setae, 1 basal seta located about the middle.

Female: Unknown.

Diagnosis

Distinguished from all species in the E. parva group in having the gonocoxal lobes distinctly curved interiorly (Fig. 7 a, b).

Etymology

From Latin arcus, bow, relating to the shape of the gonocoxal lobe.

Distribution

Afrotropical, Kenya (Fig. 4 ).

Biology

Adult collected in bamboo forest (3050 m a.s.l.).

Figures

Figure 4. Distribution map of species in the E. parva group occurring in the Afrotropical 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).