Seasonal Growth of Some Dune-Living Spiders

In populations of 20 species of spiders from sand dunes at Sandhammaren, Scania, Sweden, the frequency distributions of individuals were studied with regard to size in order to illustrate the seasonal growth. Males and females were considered separately except for the young nymphs. The material consisted of 820 samples collected in the course of well above a year. Several patterns of seasonal growth were found. Nearly all the species could finish their life cycles either in one year or in two. In Stemonyphantes lineatus (L.) one part of the population reached the adult stage in one year and another part in two years. The life cycles in the study area were twice as long as those of the same or closely related species of equal size in a warm temperate climate. The pattern of seasonal growth varied slightly between the years. The life cycle patterns could not be fitted into the usual phenological classifications, but should probably be correlated to the periods of active growth of the spiders. Pe3loMe B ilOCeJIeHH5X 20-TU THIIOB ria'KOB, HaAeHHbIX B recolIHbIX AfOHaX CaHxxraMMapa, B CKOHHHI,