Pegomya

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 : 77-78

Key to males and females of the Pegomya species feeding on sporocarps of Boletaceae and Suillaceae in Europe

Species only considered in the key are given in brackets. See Michelsen (2006a) for a taxonomic treatment of two of them, Pegomya flavoscutellata and P. curviphallis . Poorly known female Pegomya tenera not included in the key.

1 Males: Head holoptic. Sternite V broad, deeply incised at hind margin........................................... 2

- Females: Head dichoptic. Sternite V narrow, not incised at hind margin......................................... 18

2 Sternite V lobes simple ( Figs 11, 12 )..................................................................... 3

- Sternite V lobes with an obtuse outer expansion and a projecting inner lamella ( Figs 13‒15 , 28‒36 )................... 8

3 Hind femur near middle with 1 pv seta being decidedly longer that depth of femur where situated. Sternite V lobes slightly mesally expanded on distal part ( Figs 11, 12 )............................................................... 4

- Hind femur on middle part with 1‒3 pv setae about same length as depth of femur where situated. Sternite V lobes distally more or less tapering.................................................................................. 5

4 All femora, or at least mid and hind femora, mainly ochre yellow. Proepimerals: 1 seta, 3‒5 setulae. Lower calypter same size as upper calypter and slightly projecting behind it in lateral view....................................... 1. P. fulgens

- All femora mainly brownish black. Proepimerals: 1 seta, 1‒2 setulae. Lower calypter smaller than upper calypter and con- cealed behind it in lateral view...............................................................2. P. transgressa

5 Postpedicel enlarged, decidedly longer than palp. Palp yellow with dark tip. Legs entirely yellow........... [ P. deprimata ]

- Postpedicel no longer than palp. Palp entirely yellow. Legs more or less darkened on fore femur, sometimes even distally on mid and hind femora and on tarsi........................................................................ 6

6 Lower calypter much larger than upper calypter and projecting far behind it in lateral view. Abdomen dorsally orange-yellow through thin whitish dusting. Hind tibia with 3 ad setae............................................. [ P. winthemi ]

- Lower calypter about same size as upper calypter, only slightly projecting behind it. Abdomen dorsally dark beneath dense light greyish dusting. Hind tibia with 2 ad setae............................................................ 7

7 Dusting on mesonotum greyish with a golden-brownish tinge. Median dark stripe on abdomen broad, even visible on tergites I+II. Phallus curved evenly backward...................................................... [ P. flavoscutellata ]

- Dusting on mesonotum lighter, greyish. Median dark stripe on abdomen very narrow and confined to tergites III‒V. Phallus curved angularly backward................................................................ [ P. curviphallis ]

8 Fore tarsomeres II‒IV compressed, much deeper than wide, with narrow white soles. Hind femur with av setae very long on distal half, shorter and outwardly directed basal to middle ( Figs 9, 10 )........................................... 9

- Fore tarsus simple. Hind femur with av setae shorter ( Figs 6, 7 ) or forming a row of 4‒5 very long setae extended onto basal half ( Fig. 8 )........................................................................................ 10

9 Setae on postgena all golden yellow. Hind tibia with lower pd seta longer than hind tarsomere 1; subapical d seta straight and erect ( Fig. 9 )............................................................................ 12. P. scapularis

- Setae on postgena mainly black. Hind tibia with lower pd seta shorter than hind tarsomere 1; subapical d seta simple ( Fig. 10 )........................................................................................ 13. P. ringdahli

10 Setae on postgena golden yellow....................................................................... 11

- Setae on lower postgena all black, or black admixed with some yellowish ones................................... 12

11 Mid and hind femora yellow with narrow, well defined blackish tips. Hind femur with several av setae reaching a length of more than 2x depth of femur where situated ( Fig. 8 )..............................................11. P. pulchripes

- Mid and hind femora entirely yellow. Hind femur with av setae maximally 1.5x as long as depth of femur where situated................................................................................................ 8. P. tabida

12 Hind femur on subbasal half with a comb row of 7‒10 very short, spinulose pv setae ( Fig. 7 )............... 7. P. notabilis

- Hind femur without short, spinulose pv setae.............................................................. 13

13 Hind femur without pv setae on middle third.............................................................. 14

- Hind femur with 1‒3 pv setae on middle third.............................................................. 15

14 Hind femur on basal third with a row of very short, suberect pv setulae set off from surrounding ground setulae. Hind tibia with apical av seta longer than submedian av seta..................................................4. P. circumpolaris

- Hind femur without suberect pv setulae on basal third. Hind tibia with apical av seta not exceeding length of submedian av seta............................................................................................ 3. P. f u r v a

15 Basal antennal articles, basal part of postpedicel and entire palp bright yellow.................................... 16

- Basal antennal articles as a rule fuscous ochre yellow to brownish black, postpedicel entirely black; palp as a rule dark-tipped................................................................................................... 17

16 Vein C, at least distal to insertion of vein Sc, with a regular row of d setulae. Yellow mid and hind femora with a small blackish

spot at dorsal tips. Inner lamella of sternite V lobes curved downward ( Fig. 32 ).......................... 9. P. vittigera - Vein C practically bare on d surface. Femora entirely yellow. Inner lamella of sternite V lobes curved backward ( Fig. 33 ).............................................................................................10. P. incisiva

17 Larger, wing length up to 6.0mm. Mid and hind femora ochre yellow, to varying extent diffusely darkened on distal half. Inner lamella of sternite V lobes larger ( Fig. 28 ).........................................................5. P. zonata

- Smaller, wing length up to 5.3mm. Mid and hind femora yellow, contrastingly darkened on less than distal third. Inner lamella of sternite V lobes smaller ( Fig. 29 )............................................................... 6. P. tenera

18 Distal tarsomeres on mid and hind legs strikingly expanded.......................................... [ P. winthemi ]

- Tarsomeres not expanded on mid and hind legs............................................................ 19

19 Antennal postpedicel enlarged, considerably longer than palp. Thorax and abdomen entirely dark, covered in dense grey dusting; legs entirely yellow..................................................................... [ P. deprimata ]

- Postpedicel of normal size, about same length as palp. At least abdomen extensively yellow to reddish brown in ground colour.................................................................................................. 20

20 Only two pairs of orbital setae, both reclinate. Distal, permanently exposed part of tergite VI matt by dusting and with abundant hind marginal setae and setulae arranged in two irregular rows........................................... 21

- Three pairs of orbital setae, anterior pair proclinate. Tergite VI largely concealed under tergite V, shiny due to absence of dusting and with fewer hind marginal setae in one irregular row.................................................. 22

21 Grey dusting on mesonotum with a golden brownish tinge. Mesopleuron wholly dark beneath grey dusting.................................................................................................... [ P. flavoscutellata ]

- Grey dusting on mesonotum with a golden tinge. Mesopleuron in part ochre-yellow beneath grey dusting.. [ P. curviphallis ]

22 Mid and hind tarsi ventrally with dense clothing of sensilla ( Fig. 5). Oviscapt with normal hind marginal setae on segments VII and VIII; membranous parts entirely devoid of surface texture ( Figs 64‒67 )..................................... 23

- Mid and hind tarsi unremarkable. Hind marginals on segments VII and VIII reduced in size; membranous parts on anterior half of segment VIII with a scaly surface texture ( Figs 68‒76 ).................................................... 26

23 Aristal pubescence shorter, longest hairs hardly exceeding greatest basal diameter of arista. Sensilla on mid and hind tarsi expanded at tips ( Fig. 5). Oviscapt shorter, barely as long as combined length of tergites III‒V ( Fig. 66 ).............. 24

- Aristal pubescence longer, longest hairs decidedly longer than greatest basal diameter of arista. Sensilla on mid and hind tarsi not expanded at tips. Oviscapt longer, about same length as preabdomen ( Fig. 65 )................................. 25

24 Frontal vitta wholly dark or narrowly orange yellow above lunule. Hind tibia with apical av seta barely reaching length of submedian av seta................................................................................ 3. P. f u r v a

- Frontal vitta broadly orange yellow above lunule. Hind tibia with apical av seta fully as long as submedian av seta.............................................................................................. 4. P. circumpolaris

25 Larger, wing length up to 6.4mm. Postpronotal callus and scutellum mainly yellow beneath grey dusting; all femora yellow ( Fig. 2 ). Proepimerals: 1 seta, 2‒4 setulae. Hind tibia normally with 3 ad setae............................ 1. P. fulgens

- Smaller, wing length up to 5.5mm. Postpronotal callus and scutellum mainly dark beneath grey dusting; femora yellow, more or less brownish infuscated on fore femur and distal parts of mid and hind femora. Proepimerals: 1 seta, 0‒1 setula. Hind tibia with 2 ad setae.......................................................................... 2. P. transgressa

26 Smaller, wing length 4.3‒5.3mm. Hind femur with 3‒5 av setae closer together, confined to distal half; without pv setae on middle third....................................................................................... 27

- Larger species, wing length 5.0‒6.4mm. Hind femur with 3‒5 av setae more separated, occupying distal two-thirds; 1‒2 pv setae usually present on middle third..................................................................... 28

27 Postgena with golden yellow setae and setulae..................................................12. P. scapularis

- Postgena with mainly black setae and setulae................................................... 13. P. ringdahli

28 Postgena with setae and setulae golden yellow.............................................................. 29

- Postgena with setae and setulae entirely or mainly black..................................................... 30

29 Postpedicel all black. Femora yellow, mid and hind femora as a rule narrowly black-tipped.............. 11. P. pulchripes

- Postpedicel black with a yellow blotch on inner basal part. Femora wholly yellow.......................... 8. P. tabida

30 Postpedicel black with basal part bright yellow, same colour as scape and pedicel. Palp yellow. Thorax yellow, at most darkened along a median stripe on scutum and postnotum....................................................... 31

- Postpedicel black, scape and pedicel ochre yellow to brownish black. Palp more or less darkened on distal part. Thorax at least darkened on discal part of scutum and on postnotum....................................................... 32

31 Ocellar triangle outside ocellar tubercle shiny, without dusting. Thorax and abdomen dorsally rather shiny through sparse dusting. Vein C, at least distal to insertion of vein Sc, with a regular row of d setulae. Tarsi blackish............. 9. P. vittigera

- Ocellar triangle as well as thorax and abdomen mat, covered in dense dusting. Vein C practically bare dorsally. Tarsi yellow...........................................................................................10. P. incisiva

32 Setae and setulae on postgena all black. Thoracic pleura mainly dark-coloured. Cerci slender, parallel-sided, with straight outer margins ( Fig. 69 )........................................................................... 7. P. notabilis

- Postgena with black setae admixed with some yellowish setae and setulae. Thoracic pleura mainly or entirely ochre yellow. Cerci short, with convex outer margins ( Fig. 68 ).....................................................5. P. zonata

Figures

FIGURES 11 ‒ 15. Pegomya spp., male. 11 ‒ 13. Sternite V in laterodorsal view. 14, 15. Sternite V in dorsal view. Same scale.

FIGURES 28 ‒ 33. Pegomya spp., male. Sternite V in laterodorsal view. Same scale.

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

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

FIGURES 64 ‒ 67. Pegomya spp., female. Oviscapt, flat mounted. 64, 66. Entire oviscapt at same scale (0.5 mm). 65, 67. Distal oviscapt at same scale (0.25 mm).

FIGURES 68 ‒ 70. Pegomya spp., female. Distal oviscapt, flat mounted. Same scale.

FIGURES 71 ‒ 73. Pegomya spp., female. Oviscapt, flat mounted. 71, 72. Distal oviscapt at same scale (0.25 mm). 73. Entire oviscapt at scale 1.0 mm.

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.

FIGURES 1 ‒ 4. Pegomya spp., adult. 1. P. fulgens, male. 2. P. fulgens, female. 3. P. vittigera, male. 4. P. vittigera, female. Same scale.