British insects: the families of Coleoptera
British insects: the families of Coleoptera | |
~Zopheridae-Colydiinae.
Cylindrical Bark Beetles.
General appearance. 1.3–6 mm long. Body length/maximum body width 1.5–4.5. Elytral length/pronotal length 1.5–3.5. 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-oval to elongate; dorsally flattened, or dorsally strongly convex to cylindric; not necked; conspicuously waisted; unpatterned, yellow, brown, or black. Upper surfaces of body glabrous or subglabrous, or non-glabrous; exhibiting stiff, erect, dark bristles, or not bristly; exhibiting scales or scale-like setae, or with neither scales nor scale-like setae.
Detailed morphology. Eyes strongly protuberant, or not strongly protuberant; bristly, or without bristles. Antennae very short to short; (10–)11 segmented. Antennal scape not swollen. Antennae clubbed. Antennal clubs 2 segmented, or 3 segmented (oval or spherical). Antennal insertions hidden from above; not hidden by lateral extensions of the frons (being under the frontal margin). Mandibular prosthecae well developed. Prothorax longer than wide. Pronotal length/maximum pronotal width 0.4–1.75. Prothorax at its widest markedly narrower than the adjoining part of the abdomen, or not markedly narrower than the adjoining part of the abdomen; having the front corners produced, or with serrated sides (at least sometimes), or with neither produced front corners nor serrated sides (?). Prothorax without notopleural sutures. Metaventrite without a transverse groove. Fore coxal cavites open behind. Hind coxae not shaped posteriorly to receive the femur. Tarsal segmentation formula 4, 4, 4, or 3, 3, 3, or 5, 4, 4 (rarely). The tarsi without bilobed segments; without ‘hidden’ segments. Front tarsi with as many segments as the mid-tarsi; 3-segmented, or 4-segmented. Mid-leg tarsi 3-segmented, or 4-segmented; tetramerous, or trimerous. The claws of the mid-leg tarsi not appendaged. The claws of the mid-leg tarsi simple. Hind tarsi with as many segments as the mid-tarsi; 3-segmented, or 4-segmented. Elytral length/maximum width across the elytra 1–3.2. Elytra covering most to all of the abdomen; exposing no more than part of the terminal tergite; dull; rough, or tuberculate, or ribbed. Scutellary striole present, or absent. Wings well developed, or absent or much reduced. Exposed abdominal sternites 5; all articulated and movable, or comprising both fused and movable components, or all fused and immovable; immovably joined when present, 3–5. Abdominal segment 8 apparently without functional spiracles.
Adult habitat, ecology. Predacious (and some ectoparasitic on larvae or pupae of other beetles), or not predacious (mostly); mostly mycetophagous; in decaying plant material, in rotting wood, under bark, and associated with fungi.
Larvae. Larvae predacious, or not predacious (mostly); mostly mycetophagous; in decaying plant material, in rotting wood, in or under bark, and in fungi. The larvae subcylindrical, with a 9-segmented abdomen.
Classification. Suborder Polyphaga; Infraorder Cucujiformia; Superfamily Tenebrionoidea.
Worldwide and British representation. Genera about 120 (?). 17 species in Britain; genera in Britain 13; Bitoma, Cicones, Ortrhocerus, etc. E.g., Bitoma crenata (Saddle-back Bitoma); Cicones variegatus (Hornbeam Cicones); Ortrhocerus clavicornis (Hairy-horned Beetle).
General comments. Dull, cylindrical or flattened beetles, usually dark brown or black, densely punctured or coarsely sculptured and covered with tiny flattened hairs..
Illustrations. • Aglenus, Bitoma, Cicones, Colydium, Endophloeus, Myrmechixenus, Orthocerus, Oxylaemus, Synchita, Teredus (with Erotylidae): Fowler 3, 84 (1889). • Fowler 3, 84 (1889): original legend.. • Bitoma crenata (Saddle-backed Bitoma: B. Ent. 283). • Bitoma crenata (details, B. Ent. 283). • Bitoma crenata: B. Ent. 283, legend+text. • Bitoma crenata: B. Ent. 283, text cont.. • Cicones variegata Curtis (Hornbeam Cicones: B. Ent. 149). • Cicones variegata: original genus and species descriptions (B. Ent. 149, legend+text). • Cicones variegata: B. Ent. 149, text cont.). • Orthocerus clavicornis (Hairy-horned beetle: B. Ent. 314). • Orthocerus clavicornis (details, B. Ent. 314). • Orthocerus clavicornis: B. Ent. 314, legend+text. • Orthocerus clavicornis: B. Ent. 314, text cont.. • Langelandia anophthalma (with Cerylonidae and Histeridae): Fowler 3, 85 (1889). • Fowler 3, 85 (1889): original legend.. • Aulonium trisulcatum, with unrelated taxa: Fowler Suppl. 13, 1913. • Fowler Suppl. 13, 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’.
