Host Plant Specialization and Seasonality in a Polyphagous Butterfly, Polygonia C-Album (Nymphalidae)

Abstract

Larval performance and oviposition plant preferences on different natural host plants were studied in two populations of the polyphagous comma butterfly, Polygonia c-album L., from Sweden and England. Pupal weights and larval survival were similar on most hosts while larval development time differed. Ovipositing females discriminated strongly between hosts that are used by larvae in the field, in favour of hosts on which larval development was fast. Swedish females of the summer morph discriminated more strongly between hosts than those of the spring morph. English females of the summer morph discriminated more strongly than Swedish females of the summer morph. These results suggest that the degree of specialization is higher in females of generations and populations for which a fast larval development is relatively more important. Plants in the order Urticales were both most highly preferred by the females and the most suitable for the larvae. This may reflect ancestral specialization on Urticaceae in the tribe Nymphalini.