Parhelophilus
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10.a. Tars 1 and 2 darkened to black 564. above, thoracic dorsum shiny (females may have tars 1 and 2 almost yellow); femur 3 largely or entirely black: black at base, apex may be narrowly yellow. Female: frons with small dust spots › 11 10.b. Tibia and tars 1 and 2 yellow; tho- racic dorsum dull, greenish; femur 3 565. usually black with yellow base and apex (yellow base absent in 5-10% of individ- uals, yellow apex may also be absent). Female: frons with large dust spots. 6-8 mm. Northern and Central Europe, in Asia east to Pacific coast › Parasyrphus annulatus Zetterstedt 11.a. Sternites 3 and 4 with triangular dark 566. spots on hind 1/2; habitus: figure 567. marginal Males: face yellow with a black stripe; sulcus mouth edge broadly black. 8-9 mm. Northern and Central Europe, Siberia › Parasyrphus malinellus Collin 11.b. Sternites 3 and 4 with dark bands on hind 1/2. Males: face pale yellow with grey to blackish stripe; mouth edge narrowly black, occasionally pale in front. 8-9 mm. Siberia › Parasyrphus proximus Mutin figure 564. Parasyrphus malinellus, head of male. figure 565. Parasyrphus nigritarsis, head of male. figure 566. Parasyrphus nigritarsis, abdomen of male (Verlinden). PARHELOPHILUS Introduction Parhelophilus are often found close to water, where they fly around vegetation. They are found resting and sunning them- selves on leaves or visiting flowers such as Iris pseudacoris and Potentilla palustris. P. frutetorum and P. versicolor can also be found along forest edges. P. consimilis is confined to peatlands, anywhere from the vast peat- lands in the west of The Netherlands to the small peaty areas alongside streams in other areas (e.g. Eifel, Germany). The larvae live in decaying vegetation, particularly Typha, in ponds, fens and slow- moving streams. They are known as ‘rat- tailed maggots’as they have a long anal figure 567. Parasyrphus malinellus, habitus segment that they use to reach up to the of female (Verlinden). water surface for air (Rotheray, 1998). 162 Recognition Key Parhelophilus are closely allied to 1.a. Front tibiae yellow, at most with small Helophilus and share the yellowish banded dark patch at the tip; tergite 1 entirely thoracic dorsum with this genus. grey dusted; tergite 1 with median part Helophilus is generally larger and completely dusted; face less pronounced Helophilus has a bare facial stripe that is (figure 568, figure 569) › 2 lacking in Parhelophilus. Lejops and 1.b. Apical 1/4 of front tibiae black, at Anasimyia also have a banded thoracic most turning dark yellowish at the back; dorsum, but the abdomen of Lejops is tergite 1 with 2 diagonal bands of dust- marked with white longitudinal stripes ing, leaving an undusted black median and Anasimyia has two black rings on part and 2 (more or less triangular) tibia 3. Reemer (2000) adds a fourth, undusted parts laterally; face in lateral southern European species, P. crococorona- view clearly protrudes beyond frons tus, and provides a key. (figure 570). 8-10 mm. Northern Europe, northern part of Central Europe, Eastern Siberia › Parhelophilus black consimilis (Malm) hairs 568. Jizz: mesotrophic peat areas, near water. 2.a. Males (eyes separated, check tip of abdomen) › 3 2.b. Females (eyes separated, check tip of abdomen) › 4 3.a. Femur 3: near base without pos- teroventral tubercle (figure 571); face swollen in profile, clearly convex; occiput with yellow hairs only; habitus: only figure 573. 9-11 mm. Central and 569. yellow hairs Southern Europe, east to Siberia, North Africa › Parhelophilus versicolor (Fabricius) 571. 570. 572. face produced tubercle figure 568. Parhelophilus frutetorum, head of female. figure 569. Parhelophilus versicolor, head of figure 571. Parhelophilus versicolor, femur 3 male. of male (Verlinden). figure 570. Parhelophilus consimilis, head of figure 572. Parhelophilus frutetorum, femur male (Verlinden). 3 of male (Verlinden). 163.