FEEDING GUILDS OF ORIBATID MITES BASED ON THEIR CARBOHYDRASE ACTIVITIES

Carbohydrase activity was analysed in 49 species of oribatid mites and one acaridid mite sampled from natural populations. Enzyme activity was determined for the main differentiating food components: cellulose, a component of cell-walls of green plants; chitin, a component of fungal cell-walls; and trehalose, a component of fungal cell-contents. Feeding guilds were defined based on the activity of the three carbohydrases. The nomenclature of the feeding guilds was adopted from that of ruminants. Five major feeding guilds were distinguished: herbivorous grazers (9 species), fungivorous grazers (8), herbo-fungivorous grazers (16), fungivorous browsers (7) and opportunistic herbo-fungivores (8) and two minor guilds in oribatids: herbivorous browsers (1) and omnivores (1). The feeding guilds presented are operationally better defined in terms of resource exploitation than the macro-, micro- and panphytophages used hitherto.