Demes of a Puerto Rican Fleabeetle, Alagoasa bicolor (L.), Differing in Mean Body Size and Foodplant Association

Abstract

Size of the fleabeetle Alagoasa bicolor (L.) was determined measuring the living body weight and the length of the right wing in four separate demes: in Vega Alta, Vacia Talega (Loiza), El Faro (Fajardo), and Salinas. The first deme is associated with Aegiphila martinicensis Jacq., all others with Clerodendrum aculeatum (L.). The largest beetles occur in Vega Alta, the smallest in Vacia Talega, whereas those of El Faro and Salinas have similar sizes. Beetles of all four demes accept both foodplants, but tend to prefer the one to which they are associated in nature. Karyotype is the same in all demes, and copulation restrictions do not occur. From these results it is inferred that genetical isolation has not taken place between the demes, although the population biology of the species certainly facilitates such a development.