LABORATORY STUDIES ON THE LIFE CYCLE AND PREY RELATIONSHIPS OF PACHYLISTER CAFFER ERICHSON (COLEOPTERA: HISTERIDAE)

Abstract

The biology and behavior of Pachylister caffer Erichson were studied to determine the developmental history of this cattle manure-attracted, predaceous beetle and to evaluate its potential for controlling the horn fly, Haematobia irritans (L.). Females deposit eggs singly 0.5–3.0 cm deep in soil beneath cattle manure. Embryonic incubation averaged 3.9 days, larval development (two instars) 37.3 days, and pupal development 16.4 days. Development from oviposition to adult averaged 57.6 days. Prey consumption of horn fly; stable fly, Stomoxys calcitrans (L.), and house fly, Musca domestica L., pupae by P. caffer larvae was compared. Although the total weight of all prey species consumed was similar, the number of prey consumed and the development time of beetle larvae varied with prey species. Horn fly pupae accounted for 65.6% of the prey consumed, whereas stable fly and house fly pupae accounted for 26.9% and 7.5%, respectively.