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Insects of Britain and Ireland: Coleoptera-Scarabaeoidea (dung beetles and chafers) |
This data set is generated from a DELTA database (Dallwitz 1980; Dallwitz, Paine and Zurcher 1993). It is essentially a subset of the ‘Families of Coleoptera’ package (delta-intkey.com/britin/col/index.htm) which forms part of the ‘Insects of Britain and Ireland’ suite (delta-intkey.com/britin/index.htm). The latter were originally intended to present scans of the fine hand-coloured engravings of insects in John Curtis’s British Entomology: illustrations and descriptions of the genera of insects found in Great Britain and Ireland (1824–1840), of which Volumes 1–12 volumes of the first edition are available to us. For further information on this remarkable work, see Notes on John Curtis’s British Entomology. The Curtis illustrations have subsequently been supplemented from other sources listed in the References, but in the present instance we are especially indebted to Martin Halley (www.restoredprints.com) for painstakingly photographing for us the plates and text from the 1836-1840 issues dealing with Coleoptera. The manner in which Curtis’s illustrations have been extensively supplemented by plates from volumes 2-6 of Fowler’s impressive Coleoptera of the British Islands (1888-1913) and other sources, involving laborious updating of the nomenclature, is set out in the introduction to our main ‘Families of Coleoptera’ package.
In addition to presenting Curtis’s and other early illustrations, all the ‘Insects of Britain and Ireland’ subsets incorporate descriptive data organized under the DELTA system, and purport to offer facilities for attempting at least partial identification and for information retrieval, via the interactive program Intkey. The present one encompasses the British families of Coleoptera-Scarabaeoidea, extended to subfamily level for the Scarabaeidae, with taxa described via standard morphological and ecological characters and extensively illustrated. In common with our other ‘Insects of Britain and Ireland’ packages, it incorporates no original observations. Descriptions were compiled mainly from Unwin’s (1984) key to the British families, cross referenced with Joy’s Practical Handbook (1932), Britton’s (1970) detailed treatments, and Jessop’s 1986 account of British Scarabaeoidea; then greatly improved and extended using the two Lawrence et al. (1999) Intkey packages, Beetles of the World and Beetle Larvae of the World. The latter offer comprehensive, properly comparative family descriptions of adult beetles and larvae, accompanied by excellent morphological character lists, complete with detailed, illustrated glossaries and character notes, and ought now to be used for taxonomic treatments worldwide. Unfortunately, most taxonomists remain reluctant to prepare adequate taxon descriptions, and since Lawrence et al. are the only accessible source of properly comparative data in the present context, it is inevitable that our compiled family and subfamily descriptions will sometimes over-estimate the extent of variation in British representatives.
Even this early draft treatment of the British dung beetles and chafers should demonstrate the superiority of interactive identification and information retrieval over hard copy. Similar considerations apply to most of the compilations in this ‘Insects of Britain and Ireland’ series, all of which are readily accessible for extending, improving and making corrections. Organization under the Delta system ensures ready access for corrections and improvements. Criticism and constructive input are welcome, and will be appropriately acknowledged. Alternatively, complete Delta data sets can be donated if required for teaching purposes, or to any person or organization interested in developing them further.
Revised 26 July 2019