Exechia subrepanda 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 subrepanda Lindemann sp. n.

Materials

Type status: Holotype. Occurrence: catalogNumber: BIOUG22795-B10 ; recordedBy: BIObus 2014; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location : country: Canada; stateProvince: British Columbia; locality: Darkwoods Conservation Area , Grassy Lake ; verbatimElevation: 1750 m; decimalLatitude: 49.281; decimalLongitude: -117.043; Event : samplingProtocol: Pan trap; eventDate: 2014-08-25; habitat: Wetland; fieldNotes: 10 Pan Traps |Mostly overcast and rainy with wet vegetation|open marsh with willows, grass and reeds; Record Level: institutionCode: CBG Type status: Paratype. Occurrence: catalogNumber: BIOUG06394-C12 ; recordedBy: BIOBus 2012; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location : country: Canada; stateProvince: Alberta; locality: Waterton Lakes National Park , East of 2 Flags Lookout , Highway 6 pulloff ; verbatimElevation: 1562 m; decimalLatitude: 49.065; decimalLongitude: -113.778; Event : samplingProtocol: Pitfall Trap; eventDate: 2012-08-11; habitat: Forest; fieldNotes: 10 Pitfall Traps |Overcast, 19C|montane forest, douglas fir and lodgepole pine stand with aspen and birch understory; Record Level: institutionCode: CBG Type status: Paratype. Occurrence: catalogNumber: BIOUG09205-C08 ; recordedBy: BIOBus 2012; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location : country: Canada; stateProvince: Alberta; locality: Jasper National Park , Pocahontas Campground ; verbatimElevation: 1131 m; locationRemarks: Site C 21; decimalLatitude: 53.195; decimalLongitude: -117.914; Event: samplingProtocol: Intercept Trap; eventDate: 2012-07-21; habitat: Forest; fieldNotes: 1 intercept trap |overcast|16C|birch and spruce forest on a slope, lots of fallen logs; Record Level: institutionCode: CBG Type status: Paratype. Occurrence: catalogNumber: BIOUG06132-H10 ; recordedBy: BIOBus 2012; individualCount: 1; sex: female; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location : country: Canada; stateProvince: Alberta; locality: Banff National Park , Baker Creek picnic area, Adjacent to hydro line ; verbatimElevation: 1500 m; decimalLatitude: 51.35; decimalLongitude: -116.063; Event : samplingProtocol: Intercept Trap; eventDate: 2012-07-28; habitat: Forest; fieldNotes: 1 Intercept Trap |mostly sunny with a few cloudy on end date|mature forest, lodgepole pine, temperate forest; Record Level: institutionCode: CBG Type status: Paratype. Occurrence: catalogNumber: BIOUG09204-G02 ; recordedBy: BIOBus 2012; individualCount: 1; sex: female; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location : country: Canada; stateProvince: Alberta; locality: Jasper National Park , Pocahontas Campground ; verbatimElevation: 1131 m; locationRemarks: Site C 21; decimalLatitude: 53.195; decimalLongitude: -117.914; Event: samplingProtocol: Intercept Trap; eventDate: 2012-07-21; habitat: Forest; fieldNotes: 1 intercept trap |overcast|16C|birch and spruce forest on a slope, lots of fallen logs; Record Level: institutionCode: CBG

Description

Male (n = 3): Body length 3.0-3.2 mm. Wing length 2.3-2.6 mm. Colouration (Dry specimen). Head brown to dark brown; face and clypeus dark brown; labellum and palpus yellow. Antenna with scape and pedicel yellow; flagellum pale brown to brown, basal part of first flagellomere pale. Scutum and lateral sclerites brown; propleura pale brown; halteres whitish-yellow. Legs whitish-yellow. Abdomen brown. Terminalia yellow to pale brown. Head. Vertex, frons and clypeus covered with pale setae. Antenna 1.55-1.7 times as long as length from vertex to ventral margin of clypeus; flagellomeres quadrate or longer than broad, with sixth flagellomere 1.0-1.2 times as long as wide. Thorax. Scutum covered with pale setae. Legs. Fore leg with tibia (n = 1) as long as first tarsomere. Mid-tibia with (n = 2) 15-20 anterior, (n = 2) 3-4 posterodorsal, (n = 2) 6 posterior and (n = 1) 1 posteroventral bristles. Hind tibia with (n = 2) 5-7 anterodorsal, 4 posterodorsal and 3 posterior bristles. Wings. Vein r-m (n = 2) 2.2-2.7 times longer than stem of M-fork. Abdomen. Tergites covered with pale setae. Terminalia (Fig. 38 a, b, c). Each part of divided tergite IX with 8-9 setae, most apical seta stout. GL (Fig. 38 a, b) with length 0.53-0.60 of gonocoxite width; apico-internal margin slightly angled exteriorly; basal half or basal third covered with setae; apex with 3-4 setae. Aedaegal guides short with rounded or slightly angled apex (Fig. 38 a, b). Hypandrium covered with 8-12 setae with apical pair reaching about three-fourths of GL (Fig. 38 a, b). Hypandrial lobe with each branch slender, evenly tapered, apex acute. Gonostylus (Fig. 38 c) with DB 2.4-2.7 times longer than broad, curved interiorly, apical lobe well defined, apex acute or somewhat rounded; evenly covered with setae on dorsal side, except on most apical part; external margin forming distinct angle, with row of 4-5 elongate setae. VB with 2 small setae. IB apically with 1 seta close to apex and pair of setae one-third from apex. MB apex acute, with 1 seta close to the base.

Female (n = 2): Body length 2.6-3.2 mm. Wing length 2.2-2.6 mm. Colouration (Dry specimen). Head, face and clypeus dark brown; labellum and palpus yellow. Antenna with scape and pedicel yellow; flagellum pale brown, basal part of first segment pale. Scutum and lateral sclerites brown; propleura pale brown; halteres whitish-yellow. Legs whitish-yellow. Abdomen pale brown to brown, tergites III-VI with yellow lateral areas extending dorsally at anterior tenth to eighth of tergites III and IV, forming two more or less distinct pale bands. Terminalia yellow. Head. Vertex, frons and clypeus covered with pale setae. Antenna 1.65-1.67 times as long as length from vertex to ventral margin of clypeus; flagellomeres slightly longer than broad, with sixth flagellomere 1.1-1.2 times as long as wide. Thorax. Scutum covered with pale setae. Legs. Fore leg with tibia (n = 1) as long as first tarsomere. Mid-tibia with (n = 1) 16 anterior, (n = 1) 3 posterodorsal and 4-5 posterior bristles. Hind tibia with (n = 1) 7 anterodorsal, (n = 1) 5 posterodorsal and (n = 1) 4 posterior bristles. Wings. Vein r-m 2-2.7 times longer than stem of M-fork. Abdomen. Tergites covered with pale brown setae. Terminalia (Fig. 38 d, e, f). Cerci with apical segment half as long as basal segment. Tergite VIII with apicolateral margin slightly angular, not distinctly protruding (Fig. 38 d). Sternite VII with apicoventral margin evenly rounded, sometimes with medial part very slightly protruding. Sternite VIII (Fig. 38 e) with hypogynal valves separated by narrow cleft with depth about one fourth of sternite VIII length; apical seta 0.55-0.6 of sternite VIII length. Gonapophysis IX (Fig. 38 f) with basolateral part expanding in relatively obtuse angle; spermathecal eminence trilobed, in ventral view appearing cross-shaped.

Diagnosis

Distinguished from E. repanda in having the dorsal gonostylus branch 2.4-2.7 times longer than broad and with external row of setae covering only one-fifth to one-fourth of the total dorsal gonostylus branch length (Fig. 38 c); from E. neorepanda in having the dorsal gonostylus branch more curved, with external margin forming a distinct angle and with external row of setae covering only one-fifth to one-fourth of total dorsal gonostylus branch length (Fig. 38 c); from E. curvata in having the dorsal gonostylus branch with external margin forming a less protruding angle (Fig. 38 c), in combination with the gonocoxal lobe more elongate, its length 0.53-0.60 of the gonocoxite width (Fig. 38 a, b); from other species in the E. parva group in having the dorsal gonostylus branch 2.4-2.7 times longer than broad (Fig. 38 c), in combination with the gonocoxal lobes covered with setae on basal half or less and with apico-internal margin slightly angled exteriorly (Fig. 38 a, b).

Etymology

Named after the species Exechia repanda , with Latin prefix sub -, below, relating to the close resemblance to E. repanda .

Distribution

Nearctic, Canada (Fig. 13 ).

Biology

Unknown

Taxon discussion

The species is very close to E. neorepanda and E. repanda and species determination should be conducted with care or with aid of DNA barcoding.

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).