Insects of Britain and Ireland: the families of Coleoptera
Including Apoderidae, Pterocolidae, Rhynchitidae, Curculionidae part.
Leaf-rolling weevils, Giraffe weevils.
General appearance. 2–10 mm long. Body length/maximum body width 1.2–2.35. Elytral length/pronotal length 1.15–3.2. Base of prothorax 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, or elongate (head elongated, abdomen shortly oblong); conspicuously necked; somewhat waisted. Upper surfaces of body glabrous or subglabrous, or non-glabrous; not bristly; with neither scales nor scale-like setae.
Detailed morphology. Beetles equipped with a rostrum; prognathous, or not prognathous. Inclination of the head slight to very strong. Eyes strongly protuberant, or not strongly protuberant; without bristles; finely facetted. The labrum concealed beneath the clypeus; labrum if recognized as such mostly moderately to heavily sclerotized. Mandibles without a mola; without prosthecae. The mandibular apices simple, or bidentate or bilobed (some Attelabinae). The incisor edges of the mandibles simple, or with a single tooth. The maxillae with distinct galea and lacinia apically to the palp. The maxillary palps if visible, short and rigid; apical segment of the maxillary palps cylindrical to fusiform. The apical segment of the labial palps not expanded apically. Antennae short; not elbowed; 11 segmented; without a much-elongated scape. Antennal scape not swollen. Antennae clubbed. Antennal clubs 3 segmented. Antennal insertions visible from above, or hidden from above; not in fossae.
Cervical sclerites absent. Prothorax shorter than wide. Pronotal length/maximum pronotal width 0.55–2.07. The pronotum without lateral keels. Prothorax at its widest markedly narrower than the adjoining part of the abdomen. Prothorax without notopleural sutures. Scutellum conspicuous; elevated above the mesoscutum in lateral view, or not elevated; anteriorly simple; posteriorly narrowly rounded or acute, or broadly rounded or obtusely angulate, or truncate, or emarginate (very variable in Rhynchitinae). The prosternal process interrupted, or entire; if entire, complete; falling short of the mesoventrite to slightly overlapping the mesoventrite. Metaventrite without a transverse groove. The fore-leg coxae countersunk in procoxal cavities. The fore-leg coxal cavities closed behind externally; narrowly closed to broadly closed; medianly confluent; slightly transverse, or circular to longer than wide; with narrow lateral extensions, or without lateral extensions; broadly closed internally. The mid-leg coxae countersunk in mesocoxal cavities; separated by less than the shortest diameter of the cavity, or more than the shortest diameter of the cavity. The mid-leg coxal cavities contiguous, or narrowly separated, or moderately to widely separated; not or scarcely oblique, or markedly oblique; open laterally (some Rhynchitinae), or closed laterally. Hind-leg coxae contiguous or narrowly separated; not markedly extended laterally; not shaped posteriorly to receive the femur. Tarsal segmentation formula 4, 4, 4. The tarsi exhibiting bilobed segments; with a tiny penultimate segment hidden by distal lobing of the fourth and fused to the fifth. Front tarsi with as many segments as the mid-tarsi; 4-segmented, or 5-segmented (depending on interpretation). Mid-leg tarsi 4-segmented, or 5-segmented; pseudotetramerous; the penultimate segment distinctly shorter than the antepenultimate one. The claws of the mid-leg tarsi not appendaged. The claws of the mid-leg tarsi simple, or one-toothed or bifid; without an associated empodium. Hind tarsi with as many segments as the mid-tarsi; 4-segmented, or 5-segmented.
Elytral length/maximum width across the elytra 0.67–1.65. Elytra exposing no more than part of the terminal tergite to at least three complete abdominal tergites. Elytra with six or more longitudinal lines of punctures, or with six or more impressed striae, or apunctate, irregularly punctate, or each with fewer than 6 longitudinal lines of punctures or impressed striae; the lines per elytron when more than five, 9 (Attelabinae), or 10 (Rhynchitinae). Scutellary striole present, or absent. Wings well developed. Wings without an anal lobe. Wings without a medial fleck. Abdominal sternites 5; comprising both fused and moveable components. Basal abdominal sternites immovably joined 2–4. Abdominal segment 8 apparently without functional spiracles. The male external genitalia cucujiform.
Adult habitat, ecology. On living vegetation; phytophagous.
Larvae. Mature larvae minute (less than 3 mm long), or small to medium-sized. The larvae elongate and more or less parallel-sided; C-shaped in lateral view. Body circular in cross-section, or circular in cross-section to somewhat flattened. Vestiture restricted to fine hairs or setae. The larvae dorsally only very lightly pigmented or sclerotized; ventrally only very lightly pigmented. The antennae 1 segmented, or 2 segmented. Stemmata present, or absent; on either side of the larval head when present, 1–6. The frontoclypeal suture between frons and clypeus distinct. The labrum and head capsule separated by a complete suture. Apices of the mandibles bilobed or bidentate. The maxillary palps 2 segmented, or 3 segmented. The labium without ligula between the palps, or with a short ligula between the palps. Labial palps present and segmented; 2 segmented. Mesothoracic legs much reduced or absent; 0 segmented. Visible abdominal segments 10. Tergum 9 of the abdomen entirely dorsal, or entirely dorsal to extending to the underside. The abdomen having functional spiracles on anterior segments (these annular or annular-biforous); without spiracular tubes. The abdominal apex without a respiratory chamber. Abdominal tergum 8 without amature. The posterior segments without swimming hairs. The last abdominal segment without cerci.
Larvae not predacious; in living vegetation (Attelabinae in leaves of hawthorn and hazel rolled by the mothers, at least some Rhynchitinae in assorted fruits, shoots and buds); phytophagous.
Classification. Suborder Polyphaga; Superfamily Curculionoidea.
Representation in Britain and Ireland, and worldwide. About 2100 species worldwide (in 6 subfamilies). 21 species in Britain; genera in Britain 5; Attelabidae s. str.: Apoderus, Attelabus; Rhynchitidae: Byctiscus, Deporaus, Rhynchites. E.g., Attelabus nitens.
General comments. Adult labrum partly of completely fused to the clypeus or fronto-clypes, suture absent or incomplete.
Illustrations. • Attelabus nitens: B. Ent. 710. • Attelabus nitens: B. Ent. 710, legend+text. • Attelabus nitens: B. Ent. 710, text cont.. • Attelabus nitens (Janson 229). • Rhynchites ophthalmicus, cf. R. olivaceus: B. Ent.642. • Rhynchites ophthalmicus, cf. R. olivaceus: B. Ent.642, legend+text. • Rhynchites ophthalmicus, cf. R. olivaceus: B. Ent.642, text cont.. • Byctiscus populi, Rhynchites (10 spp.), Deporaus mannerheimi and D. betulae: Fowler 5, 153 (1891). • Fowler 5, 153 (1891): legend. • Apoderus coryli, Attelabus nitens, Byctiscus cf. populi (with Anthribidae and Nemonychidae): Fowler 5, 152 (1891). • Fowler 5, 152 (1891): original legend.. • Rhynchites longiceps, with unrelated taxa: Fowler Suppl. 19, 1913. • Fowler Suppl. 19, 1913: original legend.. • Rhynchites ophthalmicus: Janson 211, 219, 221.
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. Insects of Britain and Ireland: the families of Coleoptera. Version: 16th May 2016. delta-intkey.com’.