British insects: the families of Coleoptera
British insects: the families of Coleoptera |
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Tumbling Flower-beetles, Pintail beetles.
General appearance. 2–9 mm long. Body length/maximum body width 2.3–4.7. Elytral length/pronotal length 2.2–3.75. Base of prothorax not or scarcely narrower than the combined elytral bases. Greatest prothoracic width not narrower or only slightly narrower than the greatest elytral width. Beetles elongate; dorsally strongly convex (characteristically humped forward, and smoothly tapered to the uncovered tip of the abdomen); conspicuously necked; not waisted to somewhat waisted. Upper surfaces of body non-glabrous; not bristly; exhibiting scales or scale-like setae, or with neither scales nor scale-like setae.
Detailed morphology. Beetles not prognathous. Eyes not strongly protuberant; without bristles; finely facetted. Antennae short; 11 segmented. Antennal scape not swollen. Antennae filiform to gradually expanding towards the apex, or clubbed. Antennal clubs 7 segmented (elongate, serrate). Antennal insertions hidden from above. Pronotal length/maximum pronotal width 0.45–1.1. Prothorax without notopleural sutures. Metaventrite without a transverse groove. Hind coxae not shaped posteriorly to receive the femur. Tarsal segmentation formula 5, 5, 4. The tarsi without bilobed segments; without ‘hidden’ segments. Front tarsi with as many segments as the mid-tarsi; 5-segmented. Mid-leg tarsi 5-segmented; pentamerous. The claws of the mid-leg tarsi with an appendage, or not appendaged; appendages when present, not or only lightly sclerotized. The claws of the mid-leg tarsi serrate, denticulate or pectinate (serrate or pectinate beneath, and each with a sclerotized process). Hind tarsi with one segment fewer than the mid-tarsi; 4-segmented. Elytral length/maximum width across the elytra 1.55–2.53. Elytra meeting along the length of the mid-line; covering most to all of the abdomen; exposing at least one but fewer than three complete abdominal tergites (the exposed 1–2 tergites narrow-tapered to the exposed, long-pointed abdominal tip). Scutellary striole absent. Elytra non-glabrous. Wings well developed. The end of the abdomen extended as a long, narrow point beyond the ends of the truncate elytra. Exposed abdominal sternites 5; all articulated and movable. Abdominal segment 8 apparently without functional spiracles.
Adult habitat, ecology. Predacious (?), or not predacious; in living vegetation (and on tree trunks).
Larvae. Larvae predacious (or parasitic), or not predacious; on living vegetation (leaf or stem miners), or in rotting wood.
Classification. Suborder Polyphaga; Infraorder Cucujiformia; Superfamily Tenebrionoidea.
Worldwide and British representation. About 1500 species worldwide. 10 species in Britain; genera in Britain 3; Mordella, Mordellistena, Tomoxia. E.g., Mordellistena abdominalis (Red-bodied Mordella).
General comments. Small to medium sized beetles with deflexed heads, characteristically humped and smoothly tapered behind to a long, stout spine. Protectively tumbling in series of rapid jumps when alarmed.
Illustrations. • Mordellistena abdominalis (Red-bodied Mordella: B. Ent. 483). • Mordellistena abdominalis (details, B. Ent. 483). • Mordellistena abdominalis: B. Ent. 483, legend+text. • Mordellistena abdominalis: B. Ent. 483, text cont.. • Mordella fasciata and Mordellistena (5 spp.), with Scraptiidae: Fowler 5, 149 (1891). • Fowler 5, 149 (1891): original legend.. • Tomoxia biguttata, with unrelated taxa: Fowler 5, 148 (1891). • Fowler 5, 148 (1891): 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’.
