Anthony Raw

FEEDING BEHAVIOUR OF BATS AND THE DISPERSAL OF PIPER ARBOREUM SEEDS IN BRAZIL

Phyllostomide bats are the most important consumers of Piper fruits in the Neotropics (Heithaus et al. 1975) and, in particular, Carollia perspicillata and Glossophaga soricina are the species which demonstrate distinct preferences for these fruits (Charles-Dominique 1991, Fleming 1981, Fleming et al. 1977, Marinho-Filho 1991, Palmeirim el al. 1989). This is also true of Piper arboreum Aubl. (Piperaceae) in the gallery forests of Central Brazil (Bizerril & Raw 1997).

Errors in the Sex of Eggs Laid By the Solitary Bee Osmia r uFa (Megachilidae)

From calculations based on cell lengths and the locations of cells in nests it was estimated that failures in fertilization of eggs of the solitary bee Osmia rufa resulted in 6% more adult males in the population. After adjustment the sex ratio was almost exactly par.

Population densities and biomass of Neotropical social wasps (Hymenoptera, Vespidae) related to colony size, hunting range and wasp size

At a locality near Brasilia the sizes of hunting areas and of colonies of 13 species of social wasps varied greatly. Size of the hunting area varied 152 fold and was strongly related to the number of adult wasps per colony which varied 400 fold. The total number of adults of the 13 species was estimated at 182.9/ ha (range 7.1 fold among the species) and their total biomass was 1.6 kg/ ha (range 3.6 fold). Hunting range was not significantly related to body size. Variation in wing area (11.3 fold) was similar to that of the fresh weight of the adult female (10.7 fold). Eleven species showed habitat preferences where they hunted. Models relating prey size to the distance prey are carried are discussed.

Two new species of social wasps (Hymenoptera, Vespidae) from Roraima, Northern Brazil

The females and nests are described of two new species of social wasps (Hymenoptera, Vespidae) from dry evergreen forest on the Ilha de Maraca, Roraima, Brazil. Mischocyttarus (Monocyttarus) maracaensis sp.n. closely resembles M. flavicornis Zikan, 1935 in morphology and coloration. Polybia (Myrapetra) roraimae sp.n. is a member of the P. occidenlalis (Olivier, 1791) group of species.

Mischocyttarus (Kappa) santacruzi, a new species of social wasp (Hymenoptera, Vespidae) from Eastern Brazilian wet forest

The holotype female, allotype male and nest are described of a new species of social wasp, Mischocyttarus (Kappa) santacruzi (Hymenoptera, Vespidae) from Atlantic coastal forest, Bahia, State, eastern Brazil. Morphologically the species is close to M. (Kappa) adolphi Zikan.

The nest and pre-pupa of the solitary wasp Crossocerus (Cuphopterus) dimidiatus (Fabr.), with biological notes (Hymenoptera: Crabronidae)

The prepupa (post-defaecating larva) of Crossocerus (Cuphopterus) dimidiatus (Fabr.) is described and larval morphology is compared with that ctescribed by previous authors for other species of crabronid wasps. Information is given on the nest structure and the dipterous prey. The choice of nest site and prey is discussed.