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

Remarks: This species belongs to the "

anatlna" group coming close to the "

falcifera" subgroup with two species described from China. The structure of the phallic apparatus separates it from R. triangularis Schmid and the structure of tenth segment with anal sclerites differentiates it from R. falcifera Schmid. The subgroup is rather compact. I used the beautiful mountain of Tamdao, so rich in caddisfly, to name this species. Type material: Holotype ö

71 Tamdao, Vietnam, 21.01.1986, light, leg. OLÁH on white sheet with mercury vapour lamp of 250 W. Deposited in the Zoological Department, Hungarian Natural History Museum, Budapest. Right pair of wings mounted as dry microscopic preparation. Caustic potashtreated abdomen and the remaining part of the body are stored in a single airtight self-standing glass vial filled with 70% ethanol. 2 cT

1 paratypes Tamdao, Vietnam, 13.10.1986, singled, leg. OLÁH along the spring brook of the main stream at around 1400 m a.s.l. Rhyacophila mahunkai sp. n. (Fig. 3) Male (in alcohol). General colour brown. Pleuron on thorax, legs, abdominal sternites and genital appendages lighter almost yellow. Antennái annulation clearly visible on the first ten segments. Wing membrane brown, darker background pubescence mottled with golden irroration marvellously visible on freshly collected animals in day light. Darker pterostigma very outstanding on both wings. Fore-wing with cross-veins r-m, m-cu and the costal ending of cu

2 hyaline. Length and largest width of fore-wing 7.0-2.4, those of hind wing 6.1-2.2. Male genitalia. Medial ventral pointed process on seventh sternite present. Ninth segment short ventrally and produced into a dorsal process with moderately long bifid apex. Dorsal process slightly longer than preanal appendages. Granulation present on its inner surface. Preanal appendages broad triangular, regular without any apical excision or impression. Tenth segment vertical with moderately developed anal sclerites without internal root. Tergal bands lacking. Anal sclerites widely separated and reniform in ventral aspect. D Fig. 3. Rhyacophila mahunkai sp.n. A: male genitalia, lateral; B: dorsal; C: tenth segment, posterioV; D: male wings