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Tufted vetch aphidOn this page: Identification & Distribution Other aphids on the same host
Identification & Distribution
Adult apterae of Aphis craccae (see first picture below) are covered in a dense layer of grey wax powder (cf. Aphis craccivora, where the adult apterae have little or no wax on the dorsal surface, although immatures are waxed). Under the wax they have an extensive solid black shield on the dorsal abdomen which covers the whole width of tergites V and VI, and normally extends forward over the central areas of tergites I-IV, often with lateral extensions towards the intersegmental muscle sclerites. Their antennae are about the same length as the body, and the terminal process is 1.70-2.4 times the length of the base of antennal segment VI (cf. Aphis adesmiae, in South America, whose terminal process is 1.40-1.69 times the length of that segment). The dark siphunculi are 0.7-1.0 times as long as the dark, elongate, cauda (cf. Aphis craccivora, which has the siphunculi 1.1- 2.2 times the length of the cauda, and Aphis pseudocomosa, whose siphunculi are 1.1-1.6 times the caudal length). Abdominal tergite VIII usually has more than 2 hairs. The body length of adult Aphis craccae apterae is 1.9-2.8 mm.
All images above by permission, copyright Claude Pilon, all rights reserved.
Aphis craccae lives in dense, ant-attended colonies (see third picture above) on the terminal growth, flowers and seed-pods of vetches (Vicia spp.), especially tufted vetch (Vicia cracca). Oviparae and alate males appear in September. The species is widely distributed in Europe, eastward to China, Japan and Korea. It has also been introduced into north-eastern USA and Canada.
Other aphids on the same host
Aphis craccae has been recorded on 13 species of vetch (Vicia) and on one species of Lathyrus (Lathyrus japonicus, but is most commonly encountered on tufted vetch (Vicia cracca).
Blackman & Eastop list 9 species of aphid as feeding on tufted vetch (Vicia cracca) worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists 7 as occurring in Britain (Show British list).
Blackman & Eastop list 20 species of aphid as feeding on broad bean (Vicia faba) worldwide, and provide formal identification keys (Show World list). Of those aphid species, Baker (2015) lists 17 of these as occurring in Britain (Show British list).