British Insects: the Odonata
Orange-spotted Emerald Dragonfly.
Adults. Adults about 49–53–57 mm long (males somewhat the longer). Average wingspan 72 mm; hindwings 32–36 mm long.
The eyes dorsally narrowly apposed to dorsally broadly contiguous; green (in both sexes).
Legs 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 (close to the body only, in both wings of the male), or colour tinted throughout (in both wings of the female, more strongly so in the leading half). The tinting amber. The inner wing venation blackish. Discoidal cell divided longitudinally into a conspicuous triangle and supra-triangle. Antenodal veins in the forewings about 9–11 (fewer in the hindwings); without distinct primaries, and those in the costal and subcostal spaces more or less aligned. Pterostigma well over twice but no more than five times as long as wide; black (in the female), or dark brown (almost black, in the male).
Abdomen linear from base to tip to swollen both basally and distally and markedly constricted in between (quite slender, less noticeably basally swollen in the male); 36–39 mm long; predominantly green to bronze (with deep yellow markings); metallic; predominantly longitudinally lined (with a median longitudinal, interrupted deep yellow band on the green-bronze background); 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, 19–22 mm long.
The antennae 7 segmented. The mask narrowed gradually to the hinge; having the prementum hollowed dorsally; without a median cleft. The prementum bearing 22–24 major setae (11+11 to 12+12). The body of the labial palps bearing 7–8 major setae. Distal margins of the labial palps strongly crenate. Legs longer than the abdomen.
The abdomen terminating in five short spine-like appendages. The cerci more than half the length of the paraprocts. The abdomen without mid-dorsal spines; gizzard with 4–8 folds.
Distribution. Formerly central southern England (once occurring in Hampshire, probably now extinct in Britain). Adults on the wing early June to early August (generally in best mature condition mid-June to early August).
Classification. Anisoptera; family Corduliidae.
Illustrations. • Oxygastra curtisii: B. Ent. 616. • Oxygastra curtisii: B. Ent. 616, legend+text. • Oxygastra curtisii: B. Ent. 616, text cont.. • Oxygastra curtisii (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’.