British Insects: the Families of Coleoptera
British Insects: the Families of Coleoptera |
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= Parnidae; including Chiloeidae.
General appearance. 3.5–5.5 mm long. Body length/maximum body width 1.7–3.2. Elytral length/pronotal length 2–4.15. Base of prothorax not or scarcely narrower than the combined elytral bases. Greatest prothoracic width not narrower or only slightly narrower than the greatest elytral width. Beetles not necked. Upper surfaces of body glabrous or subglabrous, or non-glabrous; exhibiting stiff, erect, dark bristles, or not bristly; with neither scales nor scale-like setae.
Detailed morphology. Beetles without a rostrum. Inclination of the head slight to strong. Eyes strongly protuberant, or not strongly protuberant; bristly, or without bristles. Antennae very short to short; not strongly asymmetric; 3–6 segmented, or 8–11 segmented, or 13 segmented; clubbed and pectinate (of unusual form, with a pectinate club). Antennal clubs 6–10 segmented (‘six or more’). Antennal insertions visible from above, or hidden from above; not in fossae.
Pronotal length/maximum pronotal width 0.4–1.05. Prothorax without notopleural sutures. Metaventrite with a transverse groove, or without a transverse groove. The tarsi without bilobed segments; without ‘hidden’ segments. Mid-leg tarsi 4-segmented, or 5-segmented; pentamerous, or tetramerous. Claws of the mid-leg tarsi not appendaged. Front tarsi with as many segments as the mid-tarsi; 4-segmented, or 5-segmented. Hind tarsi with as many segments as the mid-tarsi; 4-segmented, or 5-segmented. Tarsal claws simple; without an associated empodium. Elytral length/maximum width across the elytra 1.1–2.3. Elytra covering most of the abdomen; exposing no more than part of the terminal tergite; hard. Scutellary striole absent. Elytra non-glabrous (covered with fine hairs). Wings well developed, or absent or much reduced; fringed with long hairs on the hind margin, or not fringed.
Visible abdominal sternites 5; immovably joined 2. Abdominal segment 8 with apparently functional spiracles.
Habitat, ecology. Water-beetles to land-dwellers (sub-aquatic); moving in the water by alternate, walking leg movements; not predacious; close to fresh water.
Larvae. Larvae aquatic to non-aquatic; not predacious; consuming decaying plant material and consuming rotting wood (in wet soil and leaf litter, and waterlogged wood).
Classification. Suborder Polyphaga; Superfamily Dryopoidea.
British representation. Genera 2; 8 species. E.g., Drypos luridus.
Illustrations. • Dryops luridus (Impressed Parnus: B. Ent. 080). • Dryops luridus (details, B. Ent. 080). • Dryops luridus: B. Ent. 080, legend+text.
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: the families of Coleoptera. Version: 9th June 2008. http://delta-intkey.com’.
