Carbohydrases in xylophagous coleopterous larvae cerambycidae and scarabaeidae and their evolutionary significance

Mishra, S. C.; Sen Sarma, P. K.

Detailed investigations on the origin and the distribution of various carbohydrases in the gut of Hoplocerambyx spinicornis (Cerambycidae), Anomala polita, Oxycetonia albopunctata and Xylotrupes gideon (Scarabaeidae) larvae having different food regimes were carried out. The H. spinicornis larvae possess a wide range of carbohydrases for the digestion of oligo- and polysaccharides present in living wood tissues. The association of gut microorganisms is obligatory and is solely responsible for the production of hemicellulases (xylanase, mannanase, glactanase and arabanase). The cellulase is produced by the larvae themselves. The primitive groups of larvae (Scarabaeidae) possess a very narrow enzymatic spectrum and the association of gut microorganisms appear to be facultative. The evolutionary change in food habits from humus or decayed wood to sound living wood tissues seems to have resulted in the production of a wide spectrum of carbohydrases in the digestive canal. The scarabaeid larvae X. gideon are the most primitive followed by those of O. albopunctata and A. polita. The cerambycid Stromatium barbatum and H. spinicornis are highly advanced species.