Insects of Britain and Ireland: the genera of Syrphidae (hoverflies)
Myiatropa, Myiathropa, Myatropa.
Adult flies. The flies fairly vespid wasp-like (cf. Dolichovespula and Vespula spp.); black with yellow markings; small to medium sized; 10–14 mm long. Wings 7–12 mm long.
The head about the same width as the thorax. The face not extending below beyond the antennae. The eyes depicted as hairy. Antennae relatively short, drooping; with their bases approximated. The third antennal segment ovoid or orbicular. The antennal bristle dorsal; much longer than the third segment; simple.
The humeri hairy, and readily visible behind the head. The thorax pubescent without stiff bristles interspersed; conspicuously patterned; when not worn, black with pale longitudinal and transverse markings which produce a skull-like figure; without longitudinal stripes. The scutellum at least partly yellow, or brownish, ferrugineous or tawny (to orange or ferrugineous). Wings plain; with a conspicuous dark stigma; divergent in repose to incumbent and almost parallel in repose. Wing veins R2+3 and R4+5 not forming a closed cell (but almost doing so, the veins converging at the wing margin). 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. The upper outer marginal cross-vein gently curved (almost straight); not re-entrant. The alula distinct. The hind femur distally with neither a triangular plate nor a tooth.
The abdomen wider than the thorax; obovate. The male abdomen with 4 visible segments. The abdomen not conspicuously furry; contrastingly patterned. The tergite patterning involving 2 and 3 (that on 2 much more conspicuous). The colour-patterned tergites marked with yellow. The dorsum of tergite 2 exhibiting a wineglass-shaped black area. The tergite bands bith medianly interrupted; wide (the one on tergite 2), or narrow (the less conspicuous one on tergite 3). The spiracles of the third abdominal segment borne at or near the anterior corner of each side.
Larvae and pupae. The larvae large, abruptly tapering posteriorly (when mature, about 23 mm long to the base of the approx. 28 mm tail); tailed. The anal segment abruptly constricted basally into the long, narrow tail (rat-tailed); at least as long as the rest of the body. The larvae scarcely flattened (having prolegs with crotchets in two rows); pallid, brownish, plain; without thoracic hooks; mouth without triangular sclerites; anal segments with lappets. The larvae aquatic to non-aquatic; saprophagous; associated with wet decay in trees, in sap runs, in rot-holes, in decaying sap under loose bark, in rotten wood, and in decaying tree roots.
Classification. Subfamily Milesiinae; tribe Eristalini.
British representation. 1 species in Britain (M. florea). Throughout the British Isles.
To view the illustrations with detailed captions, go to the interactive key. This also offers 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.
Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. Insects of Britain and Ireland: the genera of Syrphidae (hoverflies). Version: 28th July 2015. delta-intkey.com’.