Pegomya scapularis ( Zetterstedt, 1846 )

Michelsen, Verner, 2015, Taxonomic review of the major larval pests of bolete fungi (Boletaceae) in Europe: The Pegomya fulgens, furva and tabida species groups (Diptera: Anthomyiidae), Zootaxa 4020 (1), pp. 51-80 : 71-73

12. Pegomya scapularis ( Zetterstedt, 1846)

( Figs 9 , 35 , 44 , 53 , 62 , 75 , 76)

Anthomyza scapularis Zetterstedt, 1846: 1776 .

Pegomyia pilosa Stein, 1900b: 322 .

Pegomya pilosa Stein. Hennig 1973c: 611 (in part), plate figs 763, 904; Hackman 1976: 133 (in part); Hackman & Meinander 1979: 74 (in part); Bruns 1983: 118.

Pegomya scapularis (Zetterstedt) . Michelsen 1985: 55; Ståhls et al. 1989: 105 (in part).

Pegomya (Phoraea) scapularis (Zetterstedt) . Griffiths 1983: 238, figs 326, 331‒334.

For further references, see Hennig (1973c) and Griffiths (1983).

Description. Different from P. zonata as follows: Size. Smaller, wing length 4.3‒5.3 mm. Male. Setation on postgena all golden yellow. Fore tarsomeres 2‒4 compressed, deeper than wide, with a narrow sole of dense, white pubescence. Mid femur on basal half with 3‒5 pv setae decidedly longer than depth of femur where situated. Mid tibia with submedian ad seta very short or absent. Hind femur on distal half with a dense row of 6‒8 strikingly long av setae being up to 2.5x depth of femur where situated; this row continues onto basal half with 4‒6 shorter and more outwardly directed setae; usual basal v seta absent or setulose; 1‒3 pv setae on middle third setulose or absent ( Fig. 9 ). Hind tibia with 0‒3 short av and 3 ad setae surrounded by numerous longish ground setulae on a and av surfaces; lower pd seta longer than hind tarsomere 1 and with an upward coil distally; subapical d seta also notable by being straight and upright ( Fig. 9 ). Abdomen proportionately narrower. Terminalia ( Figs 35 , 44 , 53 , 62 ): Almost identical to those of P. ringdahli , but shape of surstyli and postgonite slightly different. Female. Scape and pedicel fuscous ochre brown; postpedicel black. Palp yellow or darkened on less than distal third. Setation on postgena all golden yellow. Mesopleuron yellow, in part with traces of dark infuscation. Femora yellow, dorsally darkened on distal quarter to distal third. Hind femur with 3‒5 av setae confined to distal half and without distinct pv setae on middle third. Oviscapt ( Figs 75, 76 ) moderately long, about same length as preabdomen. Sternite VIII pieces relatively large, only with 1‒2 setulae in front of hind marginal cluster of sensilla. Hypoproct slender spatulate, bare except for apical pair of setae and 0‒2 discal setulae. Cerci short, apically expanded and obtusely rounded.

Material examined. [ FMNH, MZLU, NHMO, ZMUB, ZMUC]. FINLAND: Regio aboensis, Nylandia, Karelia australis, Tavastia australis, Savonia australis, Tavastia borealis, Karelia borealis, Ostrobottnia kajanensis, Ostrobottnia borealis, Kuusamo, Lapponia inarensis, Lapponia enontekiensis. NORWAY: Hedmark, Oppland, Telemark, Vest-Agder, Rogaland, Hordaland, Sør-Trøndelag, Nord-Trøndelag, Nordland, Troms, Finnmark. RUSSIA: Karelia, Murmansk. SWEDEN: Halland, Småland, Västergötland, Värmland, Dalarna, Härjedalen, Jämtland, Norrbotten, Åsele Lappmark, Lycksele Lappmark, Lule Lappmark, Torne Lappmark.

Distribution. PALEARCTIC. Boreal to low arctic species. In Europe widespread in Fennoscandia including the Kola Peninsula. Southernmost Swedish records are from Enslöv in Halland and Eriksmåla in Småland. Elsewhere in Europe only listed from Poland, but this record has not been verified. Also recorded from Japan, but this may refer to Pegomya ringdahli (see below). NEARCTIC. Widespread boreal to low arctic species ranging across North America from Alaska to Massachusetts ( Griffiths 1983).

Biology. In southern Finland ( Hackman 1976, Hackman & Meinander 1979) reared from larvae in bolete sporocarps of the Boletus edulis , Leccinum versipelle and L. scabrum species groups ( Boletaceae ). The most important larval pest of Leccinum spp. in Finnish Lapland according to Ståhls et al. (1989). The female probably lays her eggs in the pores of the host fungus. Also reared from Leccinum sp. in Yukon Territory ( Griffiths 1983). Bruns (1984) reared it from species of the Leccinum scabrum and aurantiacum groups in Ontario.

Figures

FIGURES 6 ‒ 10. Pegomya spp., male. Left hind leg. Same scale.

FIGURES 34 ‒ 36. Pegomya spp., male. Sternite V in laterodorsal view. Same scale.

FIGURES 43 ‒ 45. Pegomya spp., male. Hypopygium in posterior and left lateral views. Same scale.

FIGURES 46 ‒ 54. Pegomya spp., male. Right pregonite and postgonite in lateral view. Same scale.

FIGURES 55 ‒ 63. Pegomya spp., male. Phallus in right in lateral view. Same scale.

FIGURES 74 ‒ 76. Pegomya spp., female. Oviscapt, flat mounted. 74, 75. Distal oviscapt at same scale (0.25 mm). 76. Entire oviscapt at scale 0.5 mm.