British insects: the families of Coleoptera
British insects: the families of Coleoptera | |
Including Attalomimidae, Carphuridae, Dasytidae, Gietellidae, Malachiidae, Rhadalidae.
Soft-winged Flower Beetles.
General appearance. 1.4–8 mm long. Body length/maximum body width 1.5–5.55. Elytral length/pronotal length 0.55–5.45. Base of prothorax not or scarcely narrower than the combined elytral bases, or distinctly narrower than the combined elytral bases. Greatest prothoracic width not narrower or only slightly narrower than the greatest elytral width, or distinctly narrower than greatest elytral width. Beetles elongate to slender; dorsally flattened; conspicuously necked to not necked; somewhat waisted to conspicuously waisted. 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. Eyes strongly protuberant, or not strongly protuberant; bristly, or without bristles. Antennae short to about half the insect's head to tail length; 9–11 segmented. Antennal scape swollen, or not swollen. Antennae filiform, or serrate. Antennal insertions visible from above. Mandibular prosthecae well developed to absent. Prothorax shorter than wide, or about as long as wide. Pronotal length/maximum pronotal width 0.55–1.52. Prothorax at its widest markedly narrower than the adjoining part of the abdomen, or not markedly narrower than the adjoining part of the abdomen. Prothorax without notopleural sutures. Metaventrite without a transverse groove. Tarsal segmentation formula 5, 5, 5. The tarsi exhibiting bilobed segments, or without bilobed segments; with a tiny penultimate segment hidden by distal lobing of the fourth and fused to the fifth, or without ‘hidden’ segments. Front tarsi with as many segments as the mid-tarsi, or with one segment fewer than the mid-tarsi; 5-segmented. Mid-leg tarsi 5-segmented; pentamerous, or pseudotetramerous, or tetramerous. The claws of the mid-leg tarsi with an appendage, or not appendaged; appendages when present, not or only lightly sclerotized. The claws of the mid-leg tarsi simple, or one-toothed or bifid (toothed or with a fleshy appendage beneath). Hind tarsi with as many segments as the mid-tarsi; 5-segmented. Elytral length/maximum width across the elytra 0.48–4.4. Elytra meeting along the length of the mid-line; covering most to all of the abdomen, or short, exposing several terminal abdominal tergites; exposing no more than part of the terminal tergite to at least three complete abdominal tergites; rather soft; smooth; without striae. Scutellary striole absent. Wings well developed, or absent or much reduced. Exposed abdominal sternites 6–7; all articulated and movable, or comprising both fused and movable components; immovably joined when present, 2. Abdominal segment 8 apparently without functional spiracles.
Adult habitat, ecology. Predacious; in living vegetation (often around trees or bushes, or on flowers).
Larvae. Larvae probably predacious (?); in rotting wood, or in or under bark. The larvae are said to resemble those of Cleridae.
Classification. Suborder Polyphaga; Infraorder Cucujiformia; Superfamily Cleroidea.
Worldwide and British representation. At least 550 species worldwide; genera about 60 (?). 22 species in Britain; genera in Britain 10; Anthocomus, Aplocnemus, Axinotarsus, Cerapheles, Dasytes, Dolichosoma, Ebaeus, Hypebaeus, Malachius, Psilothrix. E.g., Malachius marginellus (Spined Soft-beetle).
General comments. Adults small, rather soft-bodied, elongate and flattened.
Illustrations. • Malachius marginellus (Spined Soft-beetle: B. Ent. 167). • Malachius marginellus: B. Ent. 167, legend+text. • Malachius marginellus: B. Ent. 167, text cont.. • Anthocomus, Axinotarsus, Dasytes, Malachius and Psilothrix: Fowler 4, 114 (1890). • Fowler 4, 114 (1890): original legend. • Dolichosoma lineare, Aplocnemus nigricornis, A. impressus (= nigricornis), with Cleridae and Phloeophilus: Fowler 4, 115 (1890). • Fowler 4, 115 (1890): original legend.. • Malachius barnevelli, with unrelated taxa: Fowler Suppl. 15, 1913. • Fowler Suppl. 15, 1913: original legend.
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: 2nd January 2012. http://delta-intkey.com’.
