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Insects of Britain and Ireland: the families of Hemiptera

L. Watson and M.J. Dallwitz

Pleidae

~ Naucocoridae

Lesser Water Boatman.

Salient features of adults. Foraging under water.

Predacious. Tiny; 2–3 mm long; fliers (?), or non-fliers (hind-wings reduced); swimming and moving under water on their backs; relatively stout bodied (stout, dorsally convex). Head non-linear. Rostrum clearly separated ventrally from the prosternum by a sclerotized gula; 3 segmented. Antennae inserted underneath the head and much shorter than it, generally invisible from above; 3 segmented; non-aristate. Ocelli absent. Scutellum relatively small. Fore-wings well developed; differentiated into a basally thickened and a distally membranous region; with a clavus. Fore-legs non-raptorial. Tarsi 2 segmented, or 3 segmented. The abdomen without a respiratory siphon.

Pronotum and fore-wings coarsely pitted; head partially fused to pronotum; abdomen with a fine, laminate, ventral keel on segments 2–6; hind legs without conspicuous swimming hairs.

Taxonomy. Suborder Heteroptera; Notonectoidea.

British representation. 1 species in Britain (P. atomaria); genera 1. Plea.

Illustrations. • Plea atomaria (Southwood & Leston). • Plea atomaria, with Corixidae, Nepidae and Notonectidae: Saunders (1892).. NEPIDAE. 1, Ranatra linearis. NOTONECTIDAE. 2, Notonecta glauca. PLEIDAE. 3, Plea atomaria (as P. minutissima). CORIXIDAE. 4, Corixa punctata (as C. geoffroyi). 5–8, Sigara spp., under Corixa in the original legend. 5, Sigara concinna; 6, Sigara dorsalis (as C. striata); 7, Sigara falleni; 8, Sigara cavifrons. 9, Cymatia coleoptrata (as Corixa). 10, Micronecta scholtzi (as Sigara). From Saunders (1892).


We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, 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. See also Guidelines for using data taken from Web publications.


Cite this publication as: ‘Watson, L., and Dallwitz, M.J. 2003 onwards. Insects of Britain and Ireland: the families of Hemiptera. Version: 27th July 2019. delta-intkey.com’.

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