Exechia breviflagellata 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 breviflagellata Lindemann sp. n.

Materials

Type status: Holotype. Occurrence: catalogNumber: BIOUG27487-H10 ; recordedBy: BIObus 2014; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location : country: Canada; stateProvince: Yukon Territory; locality: Kluane National Park and Reserve , Dezadeash River Trail ; verbatimElevation: 582 m; decimalLatitude: 60.748; decimalLongitude: -137.513; Event : samplingProtocol: Intercept trap; eventDate: 2014-07-24; habitat: Wetland; fieldNotes: 1 Intercept Trap |cold and overcast on day of collection|Wetland with grasses and shrubs; Record Level: institutionCode: CBG Type status: Paratype. Occurrence: catalogNumber: BIOUG09240-B08 ; recordedBy: Chris Johnstone; individualCount: 1; sex: Female ; lifeStage: adult; preparations: Pinned , with genitalia in glycerine in separate microvial; Location : country: Canada; stateProvince: Ontario; locality: Georgian Bay Islands National Park , Administration Office , 901 Wye Valley Rd. ; verbatimElevation: 190 m; decimalLatitude: 44.7418; decimalLongitude: -79.8501; Event : samplingProtocol: Malaise Trap; eventDate: 2013-04-28; habitat: Wetland; fieldNotes: Marsh; Record Level: institutionCode: CBG Type status: Paratype. Occurrence: catalogNumber: BIOUG10611-B11 ; recordedBy: Chris Johnstone; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned , with genitalia in glycerine in separate microvial; Location : country: Canada; stateProvince: Ontario; locality: Georgian Bay Islands National Park , Administration Office , 901 Wye Valley Rd. ; verbatimElevation: 190 m; decimalLatitude: 44.7418; decimalLongitude: -79.8501; Event : samplingProtocol: Malaise Trap; eventDate: 2013-05-23; habitat: Wetland; fieldNotes: 2 Malaise traps |Marsh; Record Level: institutionCode: CBG

Description

Male (n = 2): Body length 2.9-3.2 mm. Wing length 2.3-2.5 mm. Colouration (Dry specimen). Head dark brown; face and clypeus brown; labellum pale brown; palpus whitish-yellow. Antenna with scape and pedicel brown; flagellum brown. Scutum, lateral sclerites and propleura brown; halteres whitish-yellow. Legs whitish-yellow. Abdomen brown. Terminalia yellow. Head. Frons and vertex covered with pale setae. Clypeus covered with few (15-17) pale setae, evenly distributed. Antenna short, 1.45-1.5 times as long as length from vertex to ventral margin of clypeus; flagellomeres quadrate, with sixth flagellomere 0.8-0.9 times as long as wide. Thorax. Scutum covered with short pale brown setae. Legs. Fore leg with tibia 0.96-1.0 times as long as first tarsomere. Mid-tibia with 20-21 anterior, 3-4 posterodorsal, 7-9 posterior and (n = 1) 2 posteroventral bristles. Hind tibia with 5 anterodorsal, 4-5 posterodorsal and 4-5 posterior bristles. Wings. Vein r-m 2.46-2.6 times longer than stem of M-fork. Abdomen. Tergites covered with pale brown setae. Terminalia (Fig. 12 a, b, c). Each part of divided tergite IX with about 4-5 setae, apical seta stout. Gonocoxites evenly covered with setae, except on basoventral third (Fig. 12 a, b). GL with length 0.55-0.61 of gonocoxite width, apico-internal margin slightly angled exteriorly, basal third or fourth covered with setae, apex with 3-4 setae (Fig. 12 a, b). Aedaegal guides short with acute apex (Fig. 12 a, b). Hypandrium covered with 16-19 setae, apical pair reaching about half of the GL (Fig. 12 a, b). Hypandrial lobe with each branch slender, evenly tapering. Gonostylus (Fig. 12 c) with DB 1.37-1.42 times longer than broad, short and round; apical lobe well defined, short and broad, 0.18-0.2 times as long as the total DB length, apex rounded; evenly covered with setae on dorsal side, except on most apical part; external margin evenly rounded, with row of 4-5 elongate setae. VB round, with 2 small setae. IB apically with 1 seta close to apex and pair of setae one-third from apex. MB with apex acute, 1 seta close to base.

Female (n = 1): Body length 3.1 mm. Wing length 2.7 mm. Colouration (Dry specimen). Head, face and clypeus dark brown; labellum pale brown; palpus yellow. Antenna with scape and pedicel yellow; flagellum pale brown. Scutum, lateral sclerites and propleura brown; halteres whitish-yellow. Legs whitish-yellow. Abdomen brown, tergites II-VI with paler lateral areas, not extending notably dorsally. Terminalia yellow. Head. Frons and vertex and clypeus covered with pale setae. Antenna short, 1.4 times as long as length from vertex to ventral margin of clypeus; flagellomeres broader than long, with sixth flagellomere 0.7 as long as wide. Thorax. Scutum covered with pale brown setae. Legs. Fore leg with tibia as long as first tarsomere. Hind tibia with 6 anterodorsal and 6 posterodorsal bristles. Wings. Vein r-m 2.8 times longer than stem of M-fork. Abdomen. Tergites covered with pale brown setae. Terminalia (Fig. 12 d, e). Cerci with apical segment 0.7 as long as basal segment. Tergite VIII with apicolateral margin virtually straight (Fig. 12 d). Sternite VII with apicoventral margin acuminate. Sternite VIII (Fig. 12 e) with hypogynal valves separated by wide v-shaped cleft with depth about one-sixth of sternite VIII and hypogynium length; apical seta about 0.54 times as long as sternite VIII length. Gonapophysis IX with basolateral part expanding in relatively obtuse angle; spermathecal eminence in ventral view appears cross-shaped, but with lateral branches slightly curved distally; gonapophysis IX apically with about 4 small setae.

Diagnosis

Distinguished from E. brevilobata in having the gonostylus with the dorsal branch only 1.37-1.42 times longer than broad, with its apical lobe broader and shorter, 0.18-0.2 of the total dorsal branch length (Fig. 12 c); from E. sphaerata and E. repandoides in having shorter antennae, only 1.4-1.5 times as long as length from vertex to ventral margin of clypeus, in combination with the gonostylus with the apical lobe of the dorsal branch well defined (Fig. 12 c); from other species in the E. parva group in having shorter antennae, in combination with the apico-internal margin of the gonocoxal lobe slightly angled exteriorly (Fig. 12 a, b).

Etymology

From Latin brevis, short and flagellum, whip, relating to the short antennae of the species.

Distribution

Nearctic, Canada (Fig. 13 ).

Biology

Adults collected in wetland habitats.

Figures

Figure 13. Distribution map of species in the E. parva group occurring in the Nearctic 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).