Insects of Britain and Ireland: the families of Coleoptera

DELTA home

L. Watson and M. J. Dallwitz


Including Calendridae, Chapuisidae, Cossonidae, Dryophthoridae, Erirhinidae, Ipidae, Orsodacnidae, Raymondionymidae, Rhynchophoridae, etc.; excluding Platypodidae, Scolytidae.

Weevils and Ambrosia Beetles, True Weevils, Snout Beetles.

General appearance. 1.5–14 mm long. Body length/maximum body width 1.2–5.7. Elytral length/pronotal length 0.9–4.6. 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 oval to elongate; not necked; conspicuously waisted. 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. Beetles equipped with a rostrum (see illustration of Pissodes, exemplifying morphological details). Inclination of the head slight to very strong. Eyes strongly protuberant, or not strongly protuberant; without bristles. The labrum concealed beneath the clypeus; labrum texture not recordable?. Mandibles without a mola; without prosthecae. The mandibular apices simple, or bidentate or bilobed, or multidentate or multilobed (some Dryophthorinae). The incisor edges of the mandibles variously simple, or with a single tooth, or with two or more teeth. The maxillae with a single apical structure additional 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 to about half the insect's head to tail length; usually conspicuously elbowed (inserted on the rostrum in front of the eyes, the rostrum often chanelled for reception of the scape); (1–)11(–12) segmented; with the scape much-elongated. Antennal scape not swollen. Antennae clubbed. Antennal clubs 3 segmented, or 4 segmented. Antennal insertions visible from above, or hidden from above; when recorded, not in fossae.

Cervical sclerites absent. Pronotal length/maximum pronotal width 0.42–5.7. The pronotum without lateral keels. Prothorax with notopleural sutures (usually), or without notopleural sutures (?). Scutellum conspicuous to absent; when applicable, 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. The prosternal process present; interrupted, or entire; when not interrupted, complete; falling short of the mesoventrite (mostly), or slightly overlapping the mesoventrite (Ferreria). Metaventrite without a transverse groove. The fore-leg coxae countersunk in ‘procoxal cavities’. The fore-leg coxal cavities closed behind externally; narrowly closed (Scolytinae), or broadly closed; medianly confluent, or narrowly separated, or quite widely separated; circular to longer than wide; 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 narrowly separated, or moderately to widely separated; not or scarcely oblique; closed laterally. Hind-leg coxae variously contiguous or narrowly separated, or widely separated; extending laterally to meet the elytra, or not markedly extended laterally; not shaped posteriorly to receive the femur. Tarsal segmentation formula 4, 4, 4. The tarsi exhibiting bilobed segments (usually), or without bilobed segments (rarely); with a tiny penultimate segment hidden by distal lobing of the fourth and fused to the fifth (usually), or without ‘hidden’ segments (rarely, then the third segment is not not bilobed and the claw segment is missing). Front tarsi with as many segments as the mid-tarsi; 4-segmented (usually), or 5-segmented. Mid-leg tarsi 4-segmented (rarely), or 5-segmented (usually); pseudotetramerous (nearly always), or tetramerous (rarely, when the third segment lacks the lobes, and the claw segment is missing); the penultimate segment not distinctly shorter than the antepenultimate one, or 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, or serrate, denticulate or pectinate; with an empodium between them (this with no more than two setae), or 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 0.7–4.2. Elytra exposing no more than part of the terminal tergite to at least one but fewer than three complete abdominal tergites; hard (strongly sclerotized, often clothed with scales). 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, 6–7, or 8 to 10. Scutellary striole absent. Wings well developed, or absent or much reduced; fringed with long hairs on the hind margin, or not fringed. Wings with an anal lobe, or without an anal lobe (commonly). Wings without a medial fleck. Abdominal sternites 5; all articulated and moveable, or comprising both fused and moveable components. Basal abdominal sternites immovably joined when present, 2–3 (usually the first two). Abdominal segment 8 apparently without functional spiracles. The male external genitalia curculionoid.

Adult habitat, ecology. Land-dwellers (terrestrial, but many associated with plants of wet habitats may be found struggling in water, or floating); on living vegetation, or in decaying plant material, or in rotting wood, or in dried plant material, or associated with fungi, or associated with dung, or in stored plant products; variously phytophagous (commonly,including numerous pest species), or consuming decaying plant material, or eating dried plant material or stored plant products, or consuming rotting wood, or mycetophagous, or coprophagous.

Larvae. Mature larvae minute (less than 3 mm long), or small to medium-sized. The larvae apodous; elongate and more or less parallel-sided, or oblong to ovate; C-shaped in lateral view, or not C-shaped. Body circular in cross-section to strongly 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. Stemmata present, or absent; on either side of the larval head when present, 1, or 2. The larval fronto-clypeus not extended forwardly. The frontoclypeal suture between frons and clypeus indistinct or absent, or distinct. The labrum and head capsule separated by a complete suture. Apices of the mandibles with a single lobe or tooth, or bilobed or bidentate, or trilobed or tridentate. The maxillary palps 1 segmented, or 2 segmented. The labium without ligula between the palps, or with a short ligula between the palps, or with a ligula at least as long as the palps. Labial palps present and segmented; 1 segmented, or 2 segmented. Mesothoracic legs much reduced or absent; 0 segmented. Visible abdominal segments 10. Tergum 9 of the abdomen entirely dorsal. The abdomen having functional spiracles on anterior segments (these annular, annular-uniforous or annular-biforous); without spiracular tubes. The abdominal apex without a respiratory chamber. Abdominal tergum 8 without amature. The last abdominal segment without cerci.

Larvae not predacious; in living vegetation, or in dried plant material, or in stored plant products (including cotton boll, granary rice, grain and rose weevils, etc.); phytophagous, or eating dried plant material or stored plant products (on diverse plant tissues, including stems, wood, galls, leaves, flowers, fruits, seeds - primarily feeding internally, but a few externally on leaves).

The larvae C-shaped, without legs, with small 1-segmented antennae.

Classification. Suborder Polyphaga; Superfamily Curculionoidea.

Representation in Britain and Ireland, and worldwide. About 40000 species worldwide; genera about 400. 416 species in Britain; genera in Britain about 105; Acalles, Anthonomus, Diaperis, Dryophthorus (Dryophthoridae), Ferreria (Raymondionymidae), Hypera, Lasiorhynchites, Lixus, Magdalis, Mesites, Mononychus, Notaris (Erirhinidae), Phytobius, Polydrusus, Sitophilus (Dryophthoridae), Zacladus, etc. E.g., Acalles roboris (Oak Achalles Weevil); Anthonomus pomorum (Pear-and-apple Weevil); Mesites tardii (Irish Cossonus Weevil); Diaperis boleti (Orange-spotted Diaperis); Lasiorhynchites ophthalmicus; Lixus angustatus (Narrowed Lixus Weevil, illustrated by Curtis, but probably adventive); Magdalis carbonaria (Long-nosed Magdalis Weevil); Mononychus punctumalbum (Single-clawed Weevil); Notaris aethiops; Phytobius comari (Marsh Cinqfoil Weevil); Hypera dauci (Pretty Hypera); Polydrusus sericeus (Kimpton Weevil); Zacladus geranii.

General comments. Reputed to be largest family in the animal Kingdom. Beetles variable in shape, usually more or less waisted and often clothed with scales; antennae of characteristic form.

Illustrations. • Acalles roboris (Curtis): Oak Achalles Weevil; B. Ent. 550. • Acalles roboris: B. Ent. 550, legend+text. • Acalles roboris: B. Ent. 550, text cont.. • Anthonomus pomorum (Pear-and apple Weevil: B. Ent. 562). • Anthonomus pomorum: B. Ent. 562, legend+text. • Anthonomus pomorum: B. Ent. 562, text cont.. • Baris analis: B. Ent. 766. • Baris analis: B. Ent. 766, legend+text. • Baris analis: B. Ent. 766, text cont.. • Hypera dauci (Pretty Hypera: B. Ent. 116). • Hypera dauci: B. Ent. 116, legend+text. • Hypera dauci: B. Ent. 116, legend+text. • Coleoptera: Mainland-European Lixus angustatus Fab. (Narrow Lixus Weevil). B. Ent. 542. • Lixus angustatus Fab.: B. Ent. 542, legend+text. • Lixus angustatus Fab.: B. Ent. 542, text cont.. • Magdalis carbonaria (Long-nosed Magdalis Weevil: B. Ent. 212). • Magdalis carbonaria (details, B. Ent. 212). • Magdalis carbonaria: B. Ent. 212, legend+text. • Magdalis carbonaria: B. Ent. 212, text cont.. • Mesites tardii (Curtis): Irish Cossomus Weevil, B. Ent. 59. • Mesites tardii (Curtis): B. Ent. 59, legend+text. • Mesites tardii (Curtis): B. Ent. 59, text cont.. • Miarus graminis: B. Ent. 627. • Miarus graminis: B. Ent. 627, legend+text. • Miarus graminis: B. Ent. 627, text cont.. • Mononychus punctumalbum (Single-clawed Weevil): bent292. • Mononychus punctumalbum: B. Ent. 292, legend+text. • Mononychus punctumalbum: B. Ent. 292, text cont.. • Notaris aethiops: B. Ent. 634. • Notaris aethiops: B. Ent. 634, legend+text. • Notaris aethiops: B. Ent. 634, text cont.. • Orchestes waltoni Curtis, cf. Rhynchaenus pratensis: B. Ent. 678. • Orchestes waltoni Curtis, cf. Rhynchaenus pratensis: B. Ent. 678, legend+text. • Orchestes waltoni Curtis, cf. Rhynchaenus pratensis: B. Ent. 678, text cont.. • Otiorhynchus nodosus: B. Ent. 690. • Otiorhynchus nodosus: B. Ent. 690, legend+text. • Otiorhynchus nodosus: B. Ent. 690, text cont.. • Otiorhynchus nodosus (Janson 216). • Phytobius comari (Marsh Cinqfoil Weevil: B. Ent. 558). • Polydrusus sericeus (Kimpton Weevil): B. Ent. 278. • Polydrusus sericeus: B. Ent. 278, legend+text. • Polydrusus sericeus: B. Ent. 278, text cont.. • Zacladus geranii: B. Ent. 670. • Zacladus geranii: B. Ent. 670, legend+text. • Zacladus geranii: B. Ent. 670, text cont.. • 13 species of Otiorrhynchus: Fowler 5, 157 (1891). • Fowler 5, 157 (1891): original legend.. • Caenopsis, Cathomiocerus, Peritelus, Strophosomus, Trachyphloeus: Fowler 5, 158 (1891). • Fowler 5, 158 (1891): original legend.. • Barypeithes, Brachysomus, Eusomus, Exomias Omias, Polydrusus, Strophosomus: Fowler 5, 159 (1891). • Fowler 5, 159 (1891): legend. • Polydrusus (7 spp.) and Phyllobius (6 spp.): Fowler 5, 160 (1891). • Fowler 5, 160 (1891): legend. • Alophus, Atactogenus, Barynotus, Philopedon, Phyllobius, Sitona, Tanymecus: Fowler 5, 161 (1891). • Fowler 5, 161 (1891): original legend.. • Gronops lunatus, Limobius (2 spp.), Sitona (10 spp., as Sitones): Fowler 5, 162 (1891). • Fowler 5, 162 (1891): original legend.. • Hypera (12 spp.) and Rhinocyllus conicus (as R. latirostris): Fowler 5, 163 (1891). • Fowler 5, 163 (1891): original legend.. • Chromoderus, Cleonus, Hylobius, Larinus, Leiosoma, Liparus, Lixus: Fowler 5, 164 (1891). • Fowler 5, 164 (1891): original legend.. • Pissodes, Plinthus, Rhynchaenus (9 spp.), Trachodes: Fowler 5, 165 (1891). • Fowler 5, 165 (1891): original legend.. • Grypus, Notaris, Orthocaetes, Ramphus, Rhynchaenus, Pseudostyphlus, Thryogenes: Fowler 5, 166 (1891). • Fowler 5, 166 (1891): original legend. • Bagous, Dorytomus (8 spp.), Hydronomus, Smicronyx, Tanysphyrus: Fowler 5, 167 (1891). • Fowler 5, 167 (1891): original legend.. • Acalyptus, Anoplus, Bagous (5 spp.), Elleschus, Tychius (5 spp.): Fowler 5, 168 (1891). • Fowler 5, 168 (1891): original legend.. • Gymnetron (7 spp.), Miarus, Miccotrogus, Sibinia (3 spp.): Fowler 5, 169 (1891). • Fowler 5, 169 (1891): original legend.. • Anthonomus (7 spp.), Brachonyx, Gymnetron, Mecinus (3 spp.): Fowler 5, 170 (1891). • Fowler 5, 170 (1891): original legend.. • Acalles, Cionus (5 spp.), Cleopus, Coeliodes, Cryptorrhynchus, Mononychus, Orobitis (with Nanophyes): Fowler 5, 171 (1891). • Fowler 5, 171 (1891): original legend.. • Ceutorhynchus (4 spp.), Coeliodes (4 spp.), Drupenatus, Micrelus, Poophagus, Zacladus: Fowler 5, 172 (1891). • Fowler 5, 172 (1891): original legend.. • Ceutorhynchus (13 spp.): Fowler 5, 173 (1891). • Fowler 5, 173 (1891): original legend.. • Amalus, Ceuthorhynchidius (2 spp.), Ceutorhynchus (4 spp.), Rhinoncus (4 spp.), Rutidosoma, Tapinotus: Fowler 5, 174 (1891). • Fowler 5, 174 (1891): legend. • Curculio, Baris (4 spp.), Eubrychius, Limnobaris, Litodactylus, Phytobius: Fowler 5, 175 (1891). • Fowler 5, 175 (1891): original legend.. • Curculio (6 spp., as Balaninus), Cossonus, Pentarthrum, Mesites, Rhyncolus, Sitophilus (as Calandra): Fowler 5, 176 (1891). • Fowler 5, 176 (1891): original legend.. • Caulotrupodes, Eremotes, Magdalis (5 spp.), Pselactus (with Scolytidae): Fowler 5, 177 (1891). • Fowler 5, 177 (1891): original legend.. • Laemophloeus monilis and Pediacus dermestoides, with unrelated taxa: Fowler Suppl. 13, 1913. • Fowler Suppl. 13, 1913: original legend.. • Bagous, Barypeithes, Otiorhynchus and Strophosomus, with unrelated taxa: Fowler Suppl. 19, 1913. • Fowler Suppl. 19, 1913: original legend.. • Anoplus, Anthonomus, Baris, Ceuthorhynchus, Cionus, Gymnetron and Miarus, with Pityogenes: Fowler Suppl. 20, 1913. • Fowler Suppl. 20, 1913: original legend.. • Baris analis, Miarus graminis, Rhynchaenus pratensis (Janson 202, 209, 210). • Rhynchites ophthalmicus: Janson 211, 219, 221. • Mouthparts of Pissodes, compared with a non-rostrate type. A. Pissodes strobi (Curculionidae): ventral view of rostrate head, with details of mouthparts and maxillae. B. Dytiscus marginalis (Dytiscidae): ventral view of head, with mandibles and maxillae dissected out.

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.’.