S. Mahunka szerk.: Folia Entomologica Hungarica 48. (Budapest, 1987)

Rhyacophila tamdaona sp. n. (Fig. 2) Male (in alcohol). Head, thorax and abdomen fuscous, paler beneath. Antennae fuscous with pale annulation more conspicuous on the first ten segments. Ocelli snow-white. Wing membrane dark brown with darker pubescence. Costal and subcostal area on fore-wing membrane pale, pterostigmal area along the distal third of sector radii dark granulated. Cross-veins r-m, m-cu, and the ending of cu

2 clearly hyaline. Length and largest width of fore-wing 6.8-2.3, those of hinoVwing 5.7-2.0 mm. This dark species appeared to be almost completely black on the sunshine during the netting and collecting manipulation. Fig. 2. Rhyacophila tamdaona sp.n. A: male genitalia, lateral; B: dorsal; C: tenth segment, posterior; D: male wings Male genitalia. Mediodistal long prooess on seventh sternite present. Ninth segment short ventrally and produced into a dorsal process with deeply bifid apex. Granulation present on inner surface, slightly downward curving and much longer than preanal appendages. Preanal appendages present, long triangular in lateral aspect. In dorsal aspect much shorter than the dorsal process of the ninth tergite and impressed midway. Tenth segment vertical, strongly fused with anal sclerites, apical band and preanal appendages. Anal sclerites without internal root. Tergal band lacking. In ventral aspect anal sclerites clearly separated into a pair of, both alone and together rectangular, conspicuous lateral humps. Phallotheca and endotheca well-developed. Phallobase with a strongly developed and sclerotized dorsal process. Aedeagus forms a simple rod twice longer than the dorsal process on the phallobase, and exactly as long as the first segment of the inferior appendages. Parameres rather sclerotized and slightly longer than aedeagus with gradually broadening stout distal ends clothed »in upward directed, dense thick hairs. Inferior appendages long, and slender. Terminal segment only slightly narrower at base and tapering distally due to the downcurving upper margin.