REPRODUCTION AND POSTEMBRYONIC DEVELOPMENT OF GONIOSOMA-SPELAEUM, A CAVERNICOLOUS HARVESTMAN FROM SOUTHEASTERN BRAZIL (ARACHNIDA, OPILIONES, GONYLEPTIDAE)

The reproductive characteristics of trogloxenic Goniosoma spelaeum were studied directly in the field in caves of the Ribeira River Speleological Province, Sao Paulo State, southeastern Brazil. They reproduce throughout the year, with one marked peak during the rainy season and a second minor peak in the dry season. During copulation, the male grasps the female pedipalps with his pedidalps, and the pair keep a face-to-face position. After mating, the male stays close to the female, waving his second legs over her body while she proceeds with egg-laying. Each group contains ca. 60-80 eggs of 2.1-2.3 mm diameter. Females remain over their eggs throughout embryonic development, leaving the site only after dispersion of the nymphs begins. The post-embryonic phase contains six nymphal stages, which are characterized both morphologically and morphometrically, and lasts about 1.5 years. Secondary sexual dimorphism appears during the post-embryonic development, The adult phase lasts more than 2 years, giving a total life-span of more than 3.5 years.