Gut microbiology and carbohydrate digestion in the larva ofCostelytva zealandica(Coleoptera: Scarabaeidae)

Abstract

The larval hindgut of Costelytra zealandica (White) is enlarged and contains a dense population of bacteria and flagellate protozoa. Bacteria utilising pectin and xylan were isolated, but no cellulose‐utilising bacteria were found. High invertase and amylase activities were demonstrated in the foregut. It is concluded that the larvae do not make appreciable use of the structural carbohydrates in the roots of pasture plants, but utilise the small quantities of starch and soluble sugars present. Such digestion may explain the high throughput of dietary root material and the highly destructive effect of the larvae on pasture plants.