云南真蚋二新种：（双翅目：蚋科）

TWO NEW SPECIES OF BLACKFLIES (EUSIMULIUM) FROM YUNNAN PROVINCE,CHINA (DIPTERA:SIMULIIDAE)

In this paper two new species of blackflies Eusimulium cangshanense and Eusimuliumcheni. collected from stream of Dali County, Yunnan Province are described, All the type spe-cimens are kept in the Control and Research Institute of Epidmic Diseases of Yunnan Pro-vince. The genital ventral plate of male, filaments of pupal gill. shape of cocoon of this two newspecies are quite similar to those of the Eusimulium sileste Rubzov, but the abults are guite dif-ferent in many aspects, distinguished chiefly by: Eusimulium cangshanense sp. nov. (1) the genital ventral palate of male deeply concave anteriorly and convex posteriorly;(2) genital fork of female very expanded, the 2nd segment of maxillary palpi and sensory ve-sicle expanded; (3) filaments of pupa with 2 pairs of equal branches, (4) postgenal cleft oflarva with inner margin pointed. Holotype , allotype , paratypes 11, 13, 31 pupae and 48 larvae were taken froma small stream in the mountain of Dali. Eusimulium cheni sp. nov. (1) genital ventral plate of male convex both anteriorly and posteriorly; (2) genital forkof female slightly expanded and 2nd segment of maxillry palpi and sensory vesicle stronglyexpanded; (3) pupal filaments at base unequally branched, with vesiculate pattern; (4) posge-nal cleft of larva with rounded inner margin. Holotype , allotype , paratypes 2, 2, 6 pupae and 8 larvae were taken from asmall stream in the mountain of Dali.