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| Insects of Britain and Ireland: the genera of Syrphidae (hoverflies) |
Lampetia, Syrphus p.p.
Adult flies. The flies bumblebee-like (cf. at least 5 British Bombus species), or resembling a potter bee; black, often furrily hair-banded gingerish and/or greyish to whitish on thorax and/or abdomen; small to medium sized; (10–)12–14 mm long. Wings 8.5–10.2 mm long.
The head less wide than the thorax. The face not flat or retreating between antennae and mouth; with a central knob; neither keeled nor impressed; short and smooth. The eyes hairy. Antennae relatively short, drooping. The third antennal segment ovoid or orbicular. The antennal bristle dorsal; simple (bare).
The humeri hairy, and readily visible behind the head. The thorax shaggy with soft hair; patterned, or plain (usually brown-haired anteriorly and black-haired posteriorly, with a clear line of demarcation across the middle, but brown-haired all over in a variety of M. equestris); without longitudinal stripes. The scutellum somewhat convex, with undefined edge. Wings plain (pale grey); without a conspicuously dark stigma; incumbent and almost parallel in repose. Wing veins R2+3 and R4+5 not forming a closed cell. The anterior cross vein R-M in cell R5 crossing it at or beyond the middle of the adjoining discal cell. Vein R4+5 with a conspicuous curve projecting into the cell R5; without a backwardly projecting, incomplete transverse veinlet. The lower outer marginal vein more or less parallel with the posterior wing margin. The upper and lower outer marginal cross veins more or less continuous to slightly stepped. The upper outer marginal cross-vein gently curved; re-entrant. The alula distinct. The hind femur with a large triangular plate at its distal end.
The abdomen about the same width as the thorax to narrower than the thorax; almost cylindrical, obovate (or obconical, being almost straight sided). The male abdomen with 4 visible segments. The abdomen conspicuously furry to not conspicuously furry; contrastingly patterned, or not contrastingly patterned (banded black and brown, or black and pale greyish, or tailed brown or greyish, but only owing to hair tints). The patterning when manifest, attributable to the furry hair coat. The spiracles of the third abdominal segment borne at or near the anterior corner of each side.
Larvae and pupae. The larvae broader posteriorly, tapered to the head to tapering anteriorly and posteriorly from the middle; posteriorly blunt and tail-less; no more than flattened (prolegs absent); pale brown, plain; without thoracic hooks; mouth without triangular sclerites; anal segments with lappets (the middle pair each divided into two small projections). The larvae phytophagous; feeding on Alliaceae, Amaryllidaceae, Liliaceae, Zingiberaceae, and Hyacinthaceae (etc., i.e., divers monocot bulbs and rhizomes; seemingly responsible for causing rotting of commercial narcissus and onion bulbs).
General comments. The hind femur thickened, the legs all black.
Classification. Subfamily Milesiinae; tribe Merodontini.
British representation. 1 species in Britain (M. equestris). Throughout Britain and Ireland.
Illustrations. • Merodon clavipes (Beautiful Merodon Hover-fly. Extinct British species: B. Ent. 098). • Merodon clavipes: B. Ent. 098, legend+text. • Merodon clavipes: B. Ent. 098, text cont.. • M. equestris, male (with Cheilosia and Platycheirus. SYRPHIDAE. 1, Cheilosia illustrata, male; 2, Merodon equestris, male. 3 and 4, Cheilosia (Pyrophaena) granditarsa, male with detail of fore tarsus. 5 and 6, Platycheirus peltatus, male with detail of fore tarsus. Adapted from C.O. Hammond (Colyer and Hammond, 1968), with names updated. • 15 genera (from Walker). 1, Ceriana conopsoides (adventive?), head in side view and extremity of wing. 2, Callicera aurata, with detail of antenna. 3, Microdon mutabilis, antenna and wing. 4, Eumerus strigatus, head in side view and wing. 5, Eristalis tenax: male head from above (5a), female head from the side (5b), and wing of female (5c). 6, Helophilus pendulus: head of male from above (6a) and from the side (6b), and extremity of wing (6c). 7, Merodon clavipes (extinct in Britain): head in side view, and hind leg of male. 8, Tropidia scita, male: head and extremity of wing. 9, Syritta pipiens, male, with head in side view (9a). 10, Xylota sylvarum, male: head (10a), antenna (10b), and base of hind leg showing coxa with a small spine (10d). 11, "Milesia speciosa" (Caliprobola speciosa?): head in side view (11a), wing extremity (11b), and base of hind leg (11c). 12, Criorhina berberina, with side view of head. 13, Volucella bombylans: side view of head (13a), antenna (13b), and wing extremity (13c). 14, Sericomyia silentis, with head from side (14a) and claw joint of tarsus (14b). 15, Orthoneura nobilis. From Walker (1851, Plate IX), with approximate lengths (head to abdominal tip) indicated.
We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, and distributions of character states within any set of taxa. See also Guidelines for using data taken from Web publications.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. Insects of Britain and Ireland: the genera of Syrphidae (hoverflies). Version: 27th July 2019. delta-intkey.com’.
