Relationship of habitat age to phenology among ground-dwelling Linyphiidae(Araneae) in the southeastern United States

Ground-dwelling Linyphiidae from eight South Carolina inner coastal plain h abitats were sampled for one year using pitfall traps. Habitats formed an a ge gradient, from a field disturbed yearly and pine stands aged 5, 25 and 4 0 years, to xeric, mesic and hydric hardwoods (50-75 years) and an old-grow th forest (200 years). Sixteen of the 55 trapped species were represented i n sufficient numbers (n adults greater than or equal to number of sampling periods, 26) to examine patterns of correlation between phenology and habit at distribution. Half of the species are multivoltine, characterized by adu lts present throughout the year, continuous reproduction, and overlapping g enerations. Adult abundance of these species peaked during spring through a utumn. Other species were univoltine, with adults present briefly, indicati ng synchronous reproduction and non-overlapping generations. Adult abundanc e of these species always peaked during winter months. This study examines relationships between observed voltinism patterns and characteristic habita t (distribution among the habitats) among the 16 most abundant species. Spe cies from older habitats tend to be univoltine, whereas species inhabiting more recently disturbed habitats were more likely to be multivoltine. Steno chronous winter reproduction (univoltines) probably increases survivorship by limiting individuals' exposure to the harsh conditions of the southeaste rn summer during vulnerable periods of immaturity and reproduction. This ph enological specialization appears optimal in this region except in frequent ly disturbed habitats, where rapid multivoltine reproduction is most advant ageous.