Philoponella republicana (Araneae, Uloboridae) as a commensal in the webs of other spiders
Journal of Arachnology
1995
Journal Article
23
1
1-8
animals invertebrates arthropods Arachnida spiders Araneae Uloboridae single-species study ecology commensalism Reserva Nacional Tambopata animal behavior small spatial scales Anelosimus eximius Architis Philoponella republicana predation Madre de Dios Bibliography
Juvenile individuals of the spider species, Philoponella republicana, were common in the webs of the social spider, Anelosimus eximius, and the solitary spider, Architis sp., in the forest habitats of the SE Peru. The abundance, size and location of P. republicana individuals were surveyed in each host web. Although the host webs were similar in size and conformation, more P. republicana individuals were found in the social spider webs than in the solitary host webs. Likewise, the number of P. republicana in the social spider webs was correlated with host web size. The mean size of prey captured by P. republicana was 2.1 mm, which was significantly smaller than the prey taken by the social spider, and, in feeding trials, Architis sp. individuals reacted only infrequently to prey of that size. This separation in the size of prey taken caused us to conclude that P. republicana acted as a commensal for the most part; however, they were observed to prey on the social spiders occasionally. Small P. republicana were the most common in both host webs and tended to be high in the barrier webbing. The largest individuals in the social host webs were located under the sheet area, and these individuals were observed to feed more frequently than spiders in other size classes and in other areas of the host webs. We conclude that juvenile P. republicana are commensals in both host webs but that they benefit more from the greater amount of activity in webs of the social spiders.