Mastacembelocleidus gen. n. (Monogenoidea: Dactylogyridae) is proposed to include two species collected and redescribed from spiny eels (Mastacembelidae) in India and Iraq: Mastacembelocleidus bam (Tripathi, 1959) comb. n. (syn. Ancyrocephalus bam Tripathi, 1959) from the gills of Macrognathus pancalus (new host record) and Macrognathus aculeatus (Synbranchiformes: Mastacembelidae) from Lucknow, India; and Mastacembelocleidus heteranchorus (Kulkarni, 1969) comb. n. (syn. Urocleidus heteranchorus Kulkarni, 1969) from the gills of Mastacembelus armatus from Lucknow, India, and Mastacembelus mastacembelus (new host record) from the environs of Erbil, Iraq (new locality record). Urocleidus rhyncobdelli Jain, 1959, Haliotrema tandani Agrawal et Singh, 1982 and Urocleidus raipurensis Dubey, Gupta et Agarwal, 1992 are considered junior subjective synonyms of M. bam.