Nesting behavior of Oxybelus lamellatus Olivier (Hymenoptera: Sphecidae)

Abstract

In a study carried out on Oxybelus lamellatus Olivier in eastern Spain, males emerge before females, patrolling the potential nesting area: they form mating balls and construct sleeping burrows. Females nest during the summer in dense aggregations on flat, sandy soils with almost no vegetation. They construct their nests mainly early in the morning. When excavating the nest, they push and rake soil, including the tumulus, which is leveled before provisioning begins. After the nest has been built, females orient by engaging in circular and figure-S flights. The nest consists of an oblique main burrow with a single cell, although females may add cells later to an established nest. They prey (males and females of Diptera: Brachycera) are carried in pedal and abdominal transport. Pedal carriage was used for lighter prey, whereas abdominal carriage (sting-carrying) was used for those of greater weight: for prey weight/wasp width ratios between 3.10 and 3.40, both types of carriage were observed. Thirty-five species included in 9 families were caught as prey. Eggs are laid in a Crabro-type (sensu Iwata 1942) position.