British Insects: the Odonata
Adults. Adults about 50 mm long (the sexes similar in length). Average wingspan 64 mm; hindwings 28–33 mm long.
The eyes lateral and widely separated; green (in both sexes). The three ocelli in a row.
Legs black and yellow (the coxae yellow above). Thoracic antehumeral stripes present (these wide and linked posteriorly to conspicuous humeral stripes); green. The wings spread more or less horizontally in repose; dissimilar in shape and venation; sessile; unpatterned and clear. The inner wing venation blackish. Discoidal cell divided longitudinally into a conspicuous triangle and supra-triangle. Antenodal veins in the forewings about 12–16 (fewer in the hindwings); incorporating two conspicuously stronger primaries, and those in the costal and subcostal spaces unaligned. Pterostigma well over twice but no more than five times as long as wide (rather longer in the hindwings than the forewings of both sexes); reddish brown to light brown, or orange.
Abdomen swollen both basally and distally and markedly constricted in between (in the male), or linear from a conspicuously swollen base to swollen both basally and distally and markedly constricted in between (stouter and less constricted in the female); 32–37 mm long; predominantly black (with green to yellow markings); complexly patterned, or predominantly longitudinally lined (with conspicuous median longitudinal, pale green to yellow markings on segments 1 to 6 or 7, and lateral spots of the same colour on 8 and 9); without mid-dorsal spots. The male abdomen auriculate on segment 2; with a single inferior anal appendage.
Nymphs. The nymphs stout, the body expanded in the middle; when mature, 27–30 mm long.
The eyes lateral and widely separated on the top of the head. The head in dorsal view markedly narrowing from immediately behind the eyes. The antennae 4 segmented. The mask narrowed gradually to the hinge (almost rectangular); with a flat prementum; with a short slit-like median cleft (very short), or without a median cleft. The prementum bearing 0 major setae. The body of the labial palps bearing 0 major setae. Distal margins of the labial palps entire (presenting as one large, curved tooth). Legs shorter than the abdomen; fore- and middle tarsi 2-segmented.
The abdomen terminating in five short spine-like appendages; gizzard with 4–8 folds.
Distribution. English Midlands, Wales, southeast England, and central southern England. Adults on the wing early May to late July (generally in best mature condition late May to mid-June).
Classification. Anisoptera; family Gomphidae.
General comments. A casual immigrant male of the mainland-European Gomphus flavipes was captured by J.F. Stephens near Hastings on August 15th, 1818, and a scan of his illustration of the specimen is provided here. The yellow legs streaked with black, the median dorsal yellow markings continued beyond the seventh segment to the end of the abdomen, and the different arrangement of yellowish stripes on the front of the thorax distinguish the species from G. vulgatissimus.
Illustrations. • Gomphus vulgatissimus (from Lucas). • Gomphus vulgatissimus: nymph (from Lucas). • Gomphus flavipes (a casual immigrant): from Stephens VI, 1835.
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’.