British Insects: the Families of Coleoptera
British Insects: the Families of Coleoptera |
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~Monotomidae-Rhizophaginae.
General appearance. 1.5–6 mm long. Body length/maximum body width 3–3.4. Elytral length/pronotal length 2.1–2.35. Base of prothorax distinctly narrower than the combined elytral bases. Greatest prothoracic width not narrower or only slightly narrower than the greatest elytral width. Beetles elongate; conspicuously necked to not necked; conspicuously waisted; decidedly short-legged. Upper surfaces of body glabrous or subglabrous; not bristly; with neither scales nor scale-like setae.
Detailed morphology. Beetles prognathous (and the heads of males sharply constricted behind the eyes). Inclination of the head slight. Eyes strongly protuberant; finely facetted. Antennae very short to short; 10 segmented. Antennal scape not swollen. Antennae clubbed. Antennal clubs 2 segmented (tight, spherical). Antennal insertions hidden from above; not in fossae. Mandibular prosthecae well developed.
Prothorax shorter than wide to about as long as wide. Pronotal length/maximum pronotal width 1–1.07. Prothorax at its widest not markedly narrower than the adjoining part of the abdomen. Prothorax without notopleural sutures. Metaventrite without a transverse groove. The tarsi without bilobed segments; without ‘hidden’ segments (the penultimate segment small, the basal two broad with long setae). Mid-leg tarsi 4-segmented (males), or 5-segmented (females); pentamerous, or tetramerous. Claws of the mid-leg tarsi not appendaged. Front tarsi with as many segments as the mid-tarsi; 4-segmented (males), or 5-segmented (females). Hind tarsi with as many segments as the mid-tarsi, or with one segment fewer than the mid-tarsi; 4-segmented (males), or 5-segmented (females). Tarsal claws simple; with an empodium between them (this with no more than two setae). Elytral length/maximum width across the elytra 2–2.25. Elytra meeting along the length of the mid-line; covering most of the abdomen; exposing no more than part of the terminal tergite to at least one but fewer than three complete abdominal tergites; truncate; punctate- striate. Scutellary striole absent. Elytra glabrous; with epipleura. Elytral epipleura falling short of the elytral tips. Wings well developed.
Visible abdominal sternites 5; immovably joined 0. Abdominal segment 8 apparently without functional spiracles.
Habitat, ecology. Land-dwellers; predacious, or not predacious (?); in rotting wood and under bark.
Larvae. Larvae predacious (e.g., on larvae of Scolytinae); in rotting wood and in or under bark.
Classification. Suborder Polyphaga; Superfamily Cucujoidea.
British representation. Genera 3; 21 species. E.g., Rhizophagus bipustulatus.
Illustrations. • Rhizophagus bipustulatus (Janson 136).
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: 9th June 2008. http://delta-intkey.com’.
