On the sticky cobwebs of two theridiid spiders (Araneae: Theridiidae)

Autor(es)

Gonzaga, Marcelo O. ; Leiner, Natália O. ; Santos, Adalberto J. ^[3]

• Tipo de documento: Artigo Científico
• Fonte: Journal of Natural History; v. 40, n. 5/6, p. 293-306, 2006.
• Área do conhecimento: Ciências Biológicas - Ecologia
• Assunto(s): Araneae Theridiidae Fungos Seda

Resumo

In this study we describe and illustrate a new species, Chrysso intervales n. sp., based on males and females collected in Parque Estadual Intervales, an area of Atlantic Forest in the State of S o Paulo, Brazil. We present data on habitat selection, web architecture, thread adhesiveness, diet, and mortality due to fungi for both Chrysso intervales and the sympatric species, Helvibis longicauda. Both species build webs on vegetation close to river margins, but they were not found in forest sites away from these shaded and extremely humid corridors. The webs of both species are entirely composed of viscid silk lines, occupying the space between two or more large leaves. The construction of this web type by Helvibis and Chrysso, and the large amount of viscid droplets in their threads, indicate that the investment in adhesive components in theridiids may be dependent on the ambient conditions. We suggest that the costs of maintaining viscid silk lines in humid areas may be relatively low, explaining the habitat restriction observed in the species studied. By selecting humid habitats, however, these spiders are susceptible to attacks by fungi. The webs constructed by both species intercepted mostly Diptera, especially tipulids, but H. longicauda was also observed consuming a wide variety of prey types. (AU)

• Processo FAPESP: 03/04868-3 - Biodiversidade de Salticidae (Arachnida, Araneae) da Mata Atlântica: diversidade local, similaridade entre áreas e padrões de distribuição
• Beneficiário: Adalberto José dos Santos
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 04/06072-4 - Fatores determinantes do processo de dispersão em uma espécie de aranha subsocial (Anelosimus jabaquara, Theridiidae) e suas implicações para o estabelecimento de estruturas sociais permanentes
• Beneficiário: Marcelo de Oliveira Gonzaga
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 03/03595-3 - Influência da disponibilidae de recursos nos padrões de uso do espaço e dieta de Marmosops paulensis (Marsupialia:Didelphidae) em uma área de Mata Atlântica, no Parque Estadual Intervales, SP
• Beneficiário: Wesley Rodrigues Silva
• Modalidade de apoio: Auxílio à Pesquisa - Regular