British Insects: the Odonata
Red-veined Darter Dragonfly.
Adults. Adults about 37–40–43 mm long (the sexes similar in length). Average wingspan 60 mm; hindwings 27–31 mm long.
The eyes dorsally narrowly apposed to dorsally broadly contiguous; grey (below), or brown to red (reddish brown, above).
Legs black and yellow, or black and brown (black at the sides and yellowish brown in the middle, the tarsi black). Thoracic antehumeral stripes absent. The wings spread more or less horizontally in repose; dissimilar in shape and venation; sessile; suffused with colour at their bases only. The tinting amber (or saffron). The inner wing venation mainly red (with only a few black ones). Discoidal cell divided longitudinally into a conspicuous triangle and supra-triangle. Antenodal veins in the forewings 6–8 (fewer in the hindwings). Pterostigma well over twice but no more than five times as long as wide; pale reddish brown to yellow, or red (yellowish to pale pink or reddish-brown with black edging in the male, bright yellow in the female).
Abdomen linear from a conspicuously swollen base; 24–26 mm long; predominantly red (in the male), or green, or brown (olive-yellow, in the female); plain (apart from median black dashes on segments 8 and 9 which characterize the genus), or predominantly longitudinally lined (the female also exhibiting median black lines on segments 2 and 3); without mid-dorsal spots. The male abdomen without auricles on segment 2; with a single inferior anal appendage.
Nymphs. The nymphs stout, the body expanded in the middle; when mature, 16–20 mm long.
The head in dorsal view markedly narrowing from immediately behind the eyes. The postocular lobes curving sharply to the back of the head from some distance behind the eyes. The antennae 7 segmented. The mask having the prementum hollowed dorsally. The prementum bearing 30–40 major setae (about 18+18). The body of the labial palps bearing (12–)14(–16) major setae. Legs longer than the abdomen.
The abdomen terminating in five short spine-like appendages. The cerci no more than hald the length of the paraprocts. The abdomen without mid-dorsal spines; gizzard with 4–8 folds.
Distribution. Mostly East Anglia, southeast England, and southwest England (an infrequent immigrant, with a few additional old records from the north Midlands and Wales). Adults on the wing early June to late September (generally in best mature condition late June to mid-August).
Classification. Anisoptera; family Libellulidae.
Illustrations. • Sympetrum flaveolum and S. fonscolombei (from Lucas).
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. British insects: Dragonglies and Damselflies (Odonata). Version: 1st January 2012. http://delta-intkey.com’.