Spider prey (Araneae) of Trypoxylon (Trypargilum) rogenhoferi (Hymenoptera: Sphecidae) in southeastern Brazil

Abstract

Fifty five nests and 216 cells of Trypoxylon (Trypargilum) rogenhoferi were obtained from trap-nests (cut bamboo canes) in Santa Carlota Farm (Itaoca Section=IS and Santana Section=SS), Cajuru and on the São Paulo University Campus, Ribeirão Preto (=RP), both in the State of São Paulo, Brazil (Sept. 1993 - Oct. 1995). The prey (spiders) of 40 cells from IS, 58 from SS and 39 from RP were identified. The greatest nesting frequency occurred during the hot and wet season (September to April). T. rogenhoferi preyed upon individuals of five spider families, with Araneidae (orb-weaver spiders) being the most frequent (99.6%). Alpaida aff. negro (58%) was the most frequently collected species in IS, followed by A. alto (24.8%); in SS (59.6%) and RP (64.7%) the most frequent species was A. veniliae, followed in SS by A. aff. negro (14.9%) and in RP by A. leucogramma (13.5%). The size of reproductive niches, H’=1.25 (IS), H’=1.30 (SS) and H’=1.29 (RP) were not significantly different. There was a positive correlation between the reproductive niche width (H’) and evenness.

Keywords

• Araneae
• Sphecidae
• Trypoxylon
• evenness
• reproductive niche
• trap-nests
• wasps