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

Aedeagus tripartite, a vertically bilobed sclerotized upper branch and membranous lower lobe full of granulöse matrix but with a thin sclerotized lowermost bilobed plate. Parameres situated between the upper branch and the lower lobe of aedeagus with slightly upcurving hairy ends. The real connections at the basement of the complex aedeagus confused. Interior appendages moderately long. Basal segment broad along its whole length. Terminal segment tapering with its upper margin towards the basis bearing a long, adpressed, tooth-like process. Remarks: This species belongs to the "

gyamo" group of the "

divaricata" branch. This is the single group out of the seventeen in the branch which has similar toothed terminal segment. This group contains three species and only one, R. manicata Kimmins has this type of terminal segment. In other structural units my species comes closer to R. orientális Kimmins. However, the differences from both species are very clear. The deeply excised dorsoapical lobe, the finger-like anal sclerites, the fine structure of the complex phallic apparatus and the form of inferior appendages and the combination of these characters differentiate this species and relate it to this small group. Fig. 5. Rhyacophila ranga sp.n. A: male genitalia lateral; B: dorsal; C: male wings. I named this species after the unique tooth-like process or the terminal segment so rare in this branch of the genus. Tooth = r

angin in Vietnamese. Type material: Holotype d* Tamdao, Vietnam, 21.01.1986, singled, leg. OLÁH along the main stream. Deposited in the Zoological Department, Hungarian Natural History Museum, Budapest. Right pair of wings mounted as dry microscopic preparation. Caustic potash-treated abdomen and the remaining part of the body are stored in a single airtight self-standing glass vial filled with 70 % ethanol

. Male (in alcohol). General colour dark brown. Pleuron on thorax, legs and abdominal sclerites pale. Antenna! annulation pronounced on first half and disappears afterwards. Wings are very broad with rounded apices. Membrane dark brown with darker pubescence. Costal and subcostal area not paler. Hyaline area on cross-veins r-m and m-cu and on the costal ending of cu

2 small. Length and largest width of fore wing 6.6-2.8, those of hind wing 5.7-2.4 mm. Male genitalia. Abdomen with a short pointed process on seventh sternite. Ninth segment broadened dorsaly without any dorsoapical lobe. Tenth segment composed of a bilobed dorsal branch and a longer ventral rounded lobe heavily sclerotized and granulated ventrally. Tenth segment attached directly to the dorsal process of the phallic apparatus with a pair of short bands. P*hallie apparatus very complex and long. Dorsal process well-developed and neavily sclerotized. c Rhyacophila banra sp. n. (Fig. 6)