Notes on the biology of Trypoxylon (Trypargilum) opacum Brèthes (Hymenoptera; Crabronidae) in Southern Brazil

Abstract

the present study investigated the abundance, seasonality and various life-history traits of Trypoxylon (Trypargilum) opacum. using trap-nests, 320 nests of T. opacum were collected in the parque municipal das araucárias in southern brazil (25° 23' 36" s and 51° 27' 19" W) over a 3 year period. Nesting was more frequent during the warm season. Nests consisted of a linear series of 1 to 8 brood cells separated by mud partitions, usually followed by an empty vestibular cell and final-closure mud plug. brood cells were most commonly provisioned with spiders of the family araneidae. sex-ratio was strongly female biased, 3.4:1 females:males. Natural enemies attacking nests T. opacum included chrysidids, ichneumonids, sarcophagids, bombyliids and ants.

Biology of the solitary waspTrypoxylon (Trypargilum) agamemnonRichards 1934 (Hymenoptera: Crabronidae) in trap‐nests

“…As observed for other species of Trypoxylon (Camillo et al. 1993, 1994; Buschini and Wolff 2006; Buschini et al. 2006) T. agamemnon also nidified during the warmest months of the year.…”

“…One explanation for this wasp’s preference towards this habitat could be a greater need for humid areas, with milder temperatures and lower luminosity. Buschini and Wolff (2006) observed that in this kind of habitat air humidity was significantly higher and air temperature significantly lower than in grasslands or swamp areas. This preference is not common to other species of the genus Trypoxylon .…”

“…2006), Trypoxylon tenoctitlan Richards (Coville and Coville 1980), Trypoxylon xanthandrum Richards, Trypoxylon superbum Smith (Coville and Griswold 1983, 1984), Trypoxylon vagulum Richards (Coville et al. 2000), Trypoxylon rogenhoferi Kohl (Camillo and Brescovit 1999a, 2000) and Trypoxylon opacum Brèthes (Buschini and Wolff 2006). In these species, normally the females initiate the nest in the company of a male, before they start provisioning their cells.…”

“…Here in Brazil studies are being carried out on the biology of several species of the genus (Camillo and Brescovit 1999a,b, 2000; Camillo et al. 1993, 1994; Buschini and Wolff 2006; Buschini et al. 2006; Peruquetti and Del Lama 2003; Pérez‐Maluf 1993; Morato and Campos 2000).…”

Biologic aspects of different species of Pachodynerus (Hymenoptera; Vespidae; Eumeninae)

“…In Jamaica, this species nested in partially or completely shadowed habitats. It is possible that this difference is due to the fact that the temperature in open areas in Jamaica is higher than those in Brazil, where in the hottest months it reaches a maximum 35 °C (Buschini and Wolff, 2006). According to Jayasing and Taffe (1982), the ideal temperature for the development of the eggs of P. nasidens varies from 26 to 31 °C, suggesting that Pachodynerus nests are absent from areas where the temperature is lower than 26 °C.…”