British Insects: the Families of Coleoptera
British Insects: the Families of Coleoptera |
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= Brentidae; including Antliarhinidae, Cyladidae, Eurhynchidae.
General appearance. 1.5–3.5 mm long. Body length/maximum body width 1.55–2.45. Elytral length/pronotal length 2.4–3.47. 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. Body noticeably widest immediately behind the thorax. Beetles asymmetric elongate-oval; dorsally strongly convex (abdomen very high-domed); not necked; somewhat waisted. Upper surfaces of body glabrous or subglabrous, or non-glabrous; not bristly; exhibiting scales or scale-like setae, or with neither scales nor scale-like setae.
Detailed morphology. Beetles equipped with a rostrum (this long and curved). Inclination of the head slight to strong. Eyes strongly protuberant, or not strongly protuberant; without bristles. Antennae short to about half the insect's head to tail length; not elbowed; 11 segmented; without a much-elongated scape (depite the long rostrum). Antennal scape not swollen. Antennae clubbed. Antennal clubs 1–3 segmented. Antennal insertions hidden from above; not in fossae. Mandibular prosthecae absent.
Pronotal length/maximum pronotal width 0.7–1.3. Prothorax without notopleural sutures. Metaventrite without a transverse groove. The tarsi exhibiting bilobed segments; with a tiny penultimate segment hidden by lobing of the one proximal to it. Mid-leg tarsi 5-segmented; pseudotetramerous. Claws of the mid-leg tarsi not appendaged. Front tarsi with as many segments as the mid-tarsi; 5-segmented. Hind tarsi with as many segments as the mid-tarsi; 5-segmented. Tarsal claws simple, or one-toothed or bifid; without an associated empodium. Elytral length/maximum width across the elytra 1.1–1.83. Elytra exposing no more than part of the terminal tergite. Scutellary striole absent. Wings well developed.
Visible abdominal sternites 5; immovably joined 2 (the two basal sternites enlarged and fused). Abdominal segment 8 apparently without functional spiracles.
Habitat, ecology. Not predacious; phytophagous; in living vegetation.
Larvae. Larvae not predacious; phytophagous.
Classification. Suborder Polyphaga; Superfamily Curculionoidea.
British representation. Genera 2; 73 species. E.g., Apion difforme (Eccentric Apion Weevil).
Illustrations. • Apion difforme (Eccentric Apion Weevil: B. Ent. 211). • Apion difforme (details, B. Ent. 211). • Apion difforme: B. Ent. 211, 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: 18th September 2008. http://delta-intkey.com’.
