Web contents of Nesticodes rufipes and Latrodectus geometricus (Araneaea: Theridiidae) in a Brazilian poultry house.
A study was conducted to quantify and identify the insects captured in the webs of Nesticodes rufipes and Latrodectus geometricus in a poultry house in the city of Botucatu, São Paulo, Brazil, during September 2001-August 2002. All areas in the poultry house were examined each month and insect carcasses captured in the web were collected. Results revealed that over 90% of the spiders and webs observed were either N. rufipes or L. geometricus, with N. rufipes being more abundant. The number of spiders, webs and captured insects decreased during the winter months (May-September). In general, more insects were captured in N. rufipes webs than in L. geometricus webs. However, L. geometricus webs captured more insects in November and February because only in these months when L. geometricus webs were more abundant than N. rufipes webs. 244 insects were collected, including 6 orders, 24 families, 23 genera and 16 species. Most insects belonged to the order Coleoptera (48.4%), followed by Diptera (34%), Hymenoptera (11.5%), Heteroptera (3.7%), Dermaptera (2%) and Lepidoptera (0.4%). Musca domestica was the most numerous insect observed (24.6%). Other noteworthy insects collected were Alphitobius diaperinus (20.9%), Aphodius spp. (10.2%), Gnathocerus spp. (6.1%) and Dermestes ater (3.3%). It is suggested that the natural predation by these spiders on insect pests such as M. domestica and Alphitobius diaperinus in poultry houses should be further studied as possible biological control strategy.