Abstract: This paper reports 25 cases of male fleas castrated from Heilongjiang, Jilin, Nei Mongol, Ningxia, Gansu, Hebei and Yunnan Provinces, China. They belong to 6 species (or subspecies) in genus Neopsylla: N. abagaitui (3 cases), N. bidentatiforrnis (9 cases), N. cornpar(1 case), N. pleskei orientalis (4 cases), N. sellaris (7 cases) and N. S. Specialis (1 case).The morphology of teratogenic fleas are described. Taxonomic position about Neopsylla rnonodenfatiforrnis Huang et Xie, 1987 (Ssichuan J.Zool. 7(1): 5-7) are also discussed. It will be possible that the name Neopsylla monodentati formis might be treated as an excluded name by tile International Code of Zoological Nomen clature because the name bearing type based probably on teratological specimens in N. biden.Tatiformis.

Key words: gcnus Neopsylla Wagner, 1903——castrated males——Ncopsylla mono- dentatiformis Huang et Xie, 1987 nom. Exclud, ——excluded name