Trypoxylon

Abstract: TraumatomutillaAndre, 1901 is a genus of Mutillidae Latreille, 1802 with 14 species-groups, of which the T. gemella group is one of the most poorly known. The hitherto unknown males of Traumatomutilla diophthalma (Klug, 1821), T. chuzaCasal, 1969, and T. gemellaAndre, 1906 are described and illustrated. The females of T. andrei (Cresson, 1902), T. angustata (Andre, 1906), T. chuzaCasal, 1969, T. diopthalma (Klug, 1821), and T. gemella (Andre, 1906) are redescribed. A new species, T. peismatara Bartholomay & Cambra, n. sp. (female from Peru, male from Brazil) is described. Two host records (Podium sp. from Sphecidae Latreille, 1802 and Trypoxylon sp. from Crabronidae Latreille, 1802) are provided for T. diophthalma based on trap nest data. Traumatomutilla rastraCasal, 1969 is recognized as a new synonym of T. angustata (Andre, 1906).

Abstract: Individual-level variation in resource use occurs in a broad array of vertebrate and invertebrate taxa and may have important ecological and evolutionary implications. In this study, we measured the degree of individual-level variation in prey preference of the hunting wasp Trypoxylon albonigrum, which inhabits the Atlantic Forest in southeastern Brazil. This wasp captures several orb-weaving spider genera to provision nests. Individuals consistently specialized on a narrow subset of the prey taxa consumed by the population, indicating the existence of significant individual-level variation in prey preferences. The population niche was broader in the wet season in terms of both prey size and taxa. In the case of prey size, the population niche expansion was achieved via increased individual niche breadths, whereas in the case of prey taxa, individual niches remained relatively constrained, and the population niche expanded via increased interindividual variation. The observed pattern suggests the possibility of functional trade-offs associated with the taxon of the consumed prey. The nature of the trade-offs remains unknown, but they are likely related to learning in searching and/or handling prey. We hypothesize that by specializing on specific prey taxa, individuals increase foraging efficiency, reducing foraging time and ultimately increasing reproductive success.