STRUCTURE OF MOUTHPARTS AND FEEDING-HABITS OF POTAMANTHUS-LUTEUS (LINNE) (EPHEMEROPTERA, POTAMANTHIDAE)

Feeding behaviour and morphology of the mouthparts of larvae of Potama nthus luteus (Potamanthidae) have been investigated. The results indic ate that larvae of P. luteus mainly gather food by raking movements of prothoracic legs and labial and maxillary palps. Nevertheless the lar vae have the capability of filter-feeding movements, although filter-f eeding behaviour was less frequently observed. According to the result s, the larvae of P. luteus have to be classified into the ''collector- gatherer'' functional feeding group with filter feeding capability. Th e feeding behaviour reveals a close relationship of P. luteus to Ephem erella needhami (Ephemerellidae), rather than to Antopothamus verticis , another Potamanthidae.