58.010 Colias croceus (Clouded Yellow)
ws: m52-58mm, f 54-62mm; migrant May-Oct; clovers (Trifolium spp), lucerne (Medicago sativa); commonest in coastal counties of south England but fairly common throughout England and Wales, less so in Scotland. Early migrants breed after arrival (and can produce up to 3 generations in GB). Peak numbers occur Jul-Sep when the bulk of continental migrants arrive.
Colias croceus (Clouded Yellow) §1
ID: Yellow with a broad black band along the upperside termen of both wings. The only other common yellow British butterfly is male Gonepteryx rhamni (Brimstone) which has a distinctively pointed forewing apex and hindwing termen and lacks any black marks on the forewing upperside. The female C.croceus has a pale variant (form helice) which is very similar to C.hyale (Pale Clouded Yellow) and C.alfacariensis (Berger's Clouded Yellow). In C.croceus the dark border of the hindwing extends as a band of black from the mid-costa around the apex, along the termen almost to the tornus; in C.hyale/alfacariensis the black marks are much less extensive, occurring as more discrete blotches at the ends of the veins around the hindwing apex.
Female genitalia: The ostial plate of Colias species has a pair of glandular structures near its anterolateral margins. In C.croceus these structures have a narrow opening compared with those of C.hylae (Pierce & Beirne, 1941)
Female genitalia: The ostial plate of Colias species has a pair of glandular structures near its anterolateral margins. In C.croceus these structures have a narrow opening compared with those of C.hylae (Pierce & Beirne, 1941)
§1 Foulness, Essex; 29/07/2006
§2 Foulness, Essex; 26/09/2009
§3 Keyhaven, Hampshire; 31/08/2013
§4 St Mary's, Isles of Scilly; 10/10/2022; female; fw 29.0mm; form helice
All images © Chris Lewis
§2 Foulness, Essex; 26/09/2009
§3 Keyhaven, Hampshire; 31/08/2013
§4 St Mary's, Isles of Scilly; 10/10/2022; female; fw 29.0mm; form helice
All images © Chris Lewis
Page published 02/05/2014 (§1-3) | §4 added 29/11/2022
