Exechia parva Lundstroem , 1909

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 parva Lundstroem, 1909

Exechia parva Lundström, 1909: 50 ♂ ( Lundström 1909)

Materials

Type status: Lectotype. Occurrence: recordedBy: R. Frey; individualCount: 1; sex: male; lifeStage: adult; preparations: pinned; Location : country: Finland; locality: Karislojo ; Record Level: institutionCode: MZHF Type status: Other material. Occurrence: catalogNumber: TSZD-JKJ-101428 ; recordedBy: J. Kjærandsen & M. Torp; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location: country: Norway; county: Troms; municipality: Målselv; locality: Skaktardalen N, Ovre Dividal ; locationRemarks: LVN, WT-2; decimalLatitude: 68.763; decimalLongitude: 19.724; Event : samplingProtocol: window trap; eventDate: 2015-10-07; Record Level: institutionCode: TMU Type status: Other material. Occurrence: catalogNumber: TSZD-JKJ-101682 ; recordedBy: J. Kjærandsen & M. Torp; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location: country: Norway; county: Troms; municipality: Målselv; locality: Skaktarelvmoen , Ovre Dividal ; locationRemarks: LVN, WT-1; decimalLatitude: 68.767; decimalLongitude: 19.708; Event : eventDate: 2015-07-27; Record Level: institutionCode: TMU Type status: Other material. Occurrence: catalogNumber: TSZD-JKJ-102584 ; recordedBy: J. Kjærandsen; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location: country: Norway; county: Troms; municipality: Kåfjord; locality: Kafjorddalen ; verbatimElevation: 118 m; decimalLatitude: 69.4327; decimalLongitude: 20.9674; Event : samplingProtocol: sweep net; eventDate: 2016-09-22; Record Level: institutionCode: TMU Type status: Other material. Occurrence: catalogNumber: TSZD-JKJ-102825 ; recordedBy: Rikmyrsprosjektet; individualCount: 1; sex: male; lifeStage: adult; preparations: Pinned , with genitalia in glycerine in separate microvial; Location : country: Norway; county: Hedmark; municipality: Engerdal ; locality: Asen ; locationRemarks: Site 6; decimalLatitude: 61.8859; decimalLongitude: 11.7828; Event : samplingProtocol: Malaise trap - 6; eventDate: 2016-07-16; Record Level: institutionCode: TMU Type status: Other material. Occurrence: catalogNumber: TSZD-JKJ-107532 ; recordedBy: J. Kjærandsen; individualCount: 1; sex: female; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location: country: Norway; county: Hordaland; municipality: Bømlo; locality: Vorland , Langevag ; decimalLatitude: 59.6074; decimalLongitude: 5.21117; Event : eventDate: 2003-01-26; habitat: in umbelliferous stems; Record Level: collectionID: COL-008481; institutionCode: TMU Type status: Other material. Occurrence: catalogNumber: TSZD-JKJ-107531 ; recordedBy: J. Kjærandsen; individualCount: 1; sex: female; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location: country: Norway; county: Hordaland; municipality: Bømlo; locality: Vorland , Langevag ; decimalLatitude: 59.6074; decimalLongitude: 5.21117; Event : eventDate: 2003-01-26; habitat: in umbelliferous stems; Record Level: collectionID: COL-008481; institutionCode: TMU Type status: Other material. Occurrence: catalogNumber: TSZD-JKJ-107530 ; recordedBy: J. Kjærandsen; individualCount: 1; sex: female; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location: country: Norway; county: Hordaland; municipality: Sveio ; locality: Forde ; decimalLatitude: 59.614; decimalLongitude: 5.47238; Event : eventDate: 2003-11-16; habitat: in umbelliferous stems; Record Level: collectionID: COL-008478; institutionCode: TMU Type status: Other material. Occurrence: catalogNumber: TSZD-JKJ-107529 ; recordedBy: J. Kjærandsen; individualCount: 1; sex: female; lifeStage: adult; preparations: Pinned, with genitalia in glycerine in separate microvial; Location: country: Norway; county: Hordaland; municipality: Sveio ; locality: Forde ; decimalLatitude: 59.614; decimalLongitude: 5.47238; Event : eventDate: 2003-11-16; habitat: in umbelliferous stems; Record Level: collectionID: COL-008478; institutionCode: TMU

Description

Male (n = 4): Body length 3.0-3.8 mm. Wing length 2.5-3.2 mm. Colouration (Dry specimen). Head, face and clypeus dark brown; labellum and palpus yellow to pale brown. Antenna with scape and pedicel yellow; flagellum dark brown to pale brown, basal half of first flagellomere pale. Scutum dark brown; lateral sclerites and propleura brown to dark brown; halteres whitish-yellow. Legs yellow to whitish-yellow. Abdomen brown to dark brown, tergites I-III slightly paler, sometimes tergite II with pale area confined to a narrow stripe along ventral margin. Terminalia yellow. Head. Vertex, frons and clypeus covered with pale setae. Antenna (n = 2) 1.8-2 times as long as length from vertex to ventral margin of clypeus; flagellomeres longer than broad, with sixth flagellomere 1.1-1.3 times as long as wide. Thorax. Scutum covered with pale to pale brown setae. Legs. Fore leg with tibia (n = 1) 0.95 times as long as first tarsomere. Mid-tibia with 18-22 anterior, 3-4 posterodorsal, 4-8 posterior and (n = 2) 2-3 posteroventral bristles. Hind tibia with (n = 3) 6-8 anterodorsal, (n = 2) 5 posterodorsal and (n = 2) 4 posterior bristles. Wings. Vein r-m (n = 2) 2.45-2.5 times longer than stem of M-fork. Abdomen. Tergites covered with pale to pale brown setae. Terminalia (Fig. 28 a, b, c). Each part of divided tergite IX with 6-8 setae, 2 most apical setae stout. GL with length 0.33-0.4 of gonocoxite width, evenly tapered, apico-internal margin slightly angled exteriorly, entire length covered with setae, apex with 3-4 setae (Fig. 28 a, b). Aedaegal guides short and round (Fig. 28 a). Hypandrium covered with 10-12 setae, with apical pair reaching about half of the GL (Fig. 28 a). Hypandrial lobe with each branch basally wide, apical half narrow, apex rounded. Gonostylus (Fig. 28 c) with DB 1.4-1.6 times longer than borad, short and round, slightly curved interiorly; apical lobe well defined, short and narrow, apex rounded; dorsal side evenly covered with setae, except on most apical part; medio-external margin angled, with row of 4-5 short setae. VB with 2 small setae. IB apically with 1 seta close to the apex and pair of setae one-fourth from apex. MB short, curved interiorly, apex acute, with 1 seta close to the base.

Female (n = 4): Body length 3.3-3.9 mm. Wing length 2.9-3.2 mm. Colouration (Dry specimen). Head, face and clypeus brown to dark brown; labellum and palpus yellow. Antenna with scape and pedicel yellow; flagellum pale brown to brown, basal part of first flagellomere pale. Thorax with scutum brown to dark brown; lateral sclerites pale brown to brown; halteres whitish-yellow; wings hyaline tinged with brown. Legs whitish-yellow. Abdomen brown to dark brown, tergites III-VI with lateral pale areas, extending from lateral margin to about half tergal height. Terminalia pale brown. Head. Vertex, frons and clypeus covered with pale setae. Antenna (n = 2) 1.7-1.8 times as long as length from vertex to ventral margin of clypeus; flagellomeres quadrate, with sixth flagellomere as long as broad. Thorax. Scutum covered with pale brown setae. Legs. Fore leg with tibia 0.93-1.0 times as long as first tarsomere. Mid-tibia with 23-26 anterior, 3-4 posterodorsal, 6-8 posterior and 2-3 posteroventral bristles. Hind tibia with 5-6 anterodorsal, 5 posterodorsal and 3-5 posterior bristles. Wings. Vein r-m (n = 2) 2.7-2.8 times longer than stem of M-fork. Abdomen. Tergites covered with pale brown setae. Terminalia (n = 3, Fig. 28 d, e). Cerci with apical segment 0.57-0.65 times as long as basal segment. Tergite VIII with apicolateral margin slightly angular or virtually straight. Sternite VII with apicoventral margin angular or slightly acuminate, apex truncate. Sternite VIII (Fig. 28 d) with hypogynal valves separated by a wide cleft with depth about one-seventh of sternite VIII length; apical lobes almost as long as breadth of hypogynial valve in ventral view; apical seta length 0.67-0.73 of sternite VIII medial length. Gonapophysis IX (Fig. 28 e) with basolateral part expanding in a relatively obtuse angle; spermathecal eminence in ventral view trifurcate with middle branch large and round and lateral branches short.

Diagnosis

Distinguished from all species in the E. parva group in having the gonocoxal lobe evenly tapered and entirely covered with setae (Fig. 28 a, b), in combination with the gonocoxal lobes with apico-internal margin slightly angled exteriorly (Fig. 28 a, b) and the internal branch of the gonostylus with only one seta close to the apex (Fig. 28 c).

Distribution

East Palaearctic, West Palaearctic, Austria, Belgium, Britain, Bulgaria, Croatia, Czech Republic, Estonia, Finland, France, Germany, Ireland, Latvia, Norway, Poland, Russia, Slovenia, Sweden, Switzerland, The Netherlands ( Polevoi and Barkalov 2017, Chandler 2005, Fig. 15 ).

Biology

Reared from fruitbody of Nematoloma sp. [? udum (Pers.: Fr.) Karst.] = Hypholoma sp. [? udum (Pers.: Fr.) Kühner], Ptychoverpa bohemica (Krombh.) Boud. = Verpa bohemica (Krombh.) J. Schröt, and Russula ochroleuca (Pers.) Fr. ( Plassmann 1971, Jakovlev 1994, Hackman and Meinander 1979). Larvae, determined with DNA barcodes, have been collected from fruitbody of Cortinarius sp.

Adults have frequently been reported hibernating in hollow, usually broken, umbelliferous stems ( Plassmann 1971, Väisänen 1981, Kurina 1997) and we have also collected adults from broken stems of Anthriscus sylvestris (L.) Hoffm. and Heracleum persicum Desf. ex Fisch. at different localities in Norway during the winter season.

Taxon discussion

Chandler (1977) noticed two types of abdominal pattern in females matching the illustration of female terminalia of E. parva in Plassmann (1970). In our material, all female specimens of E. parva match the first type mentioned by Chandler (1977), with "[...] small yellow patches on tergites 3-6 not more than half tergal height in lateral view".

Figures

Figure 15. Distribution map of species in the E. parva group occurring in the West Palaearctic 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).