Territorial Behavior in Males of Philanthus Psyche (Hymenoptera, Sphecidae)

The comparative ethology of the family Sphecidae has been the subject of intensive study over the last thirty years, although the behavior of these wasps was observed and recorded by Fabre as early as the mid-1800’s. The majority of work has been done on females, probably because of the conspicuousness of their activities and their complex, species-specific behavior patterns. In the past few years, an increasing amount of work has concentrated on the behavior of male sphecids, revealing complex and sometimes puzzling behavior patterns. Lin’s paper (1963) on male territoriality in Sphecius speciosus was one of the first attempts at a rigorous study of male behavior. The conspicuousness of female activity is often matched by the inconspicuousness of the males, particularly when they do not frequent the nesting area subsequent to emergence. Even when males are easily observed, in the nesting area or elsewhere, matings are rarely observed. Male sphecids, except in a few species, do not participate in the nesting activities of the females. Alcock et al. (1978) classify the mating strategies of male aculeate Hymenoptera as taking the form of either searching for females (e.g., the "sun dance" of Nyssonine sand wasps, Evans 1966) or waiting for (e.g., territoriality) females at particular localities where they are most likely to be found. The distribution of receptive females in time and space has been a major influence on the evolution of male mating strategies. A recent review of territorial behavior in male sphecids (Alcock 1975a) shows that in all known cases this behavior is associated with securing females for copulation. I define territoriality here as "a fixed area from which intruders are excluded by some combination of advertisement, threat or