Three new species of free-living marine nematodes Micoletzkyia longispicula sp. nov., Micoletzkyia filicaudata sp. nov. and Micoletzkyia nanhaiensis sp. nov. from the Yellow Sea and the South China Sea are described. Micoletzkyia longispicula sp. nov. is characterized by spicules elongated and straight, 7 a.b.d. long, pear-shaped proximally and pointed distally; gubernaculum conical, without apophysis, and tubular supplement headlike proximally. Micoletzkyia filicaudata sp. nov. is characterized by slender body with relatively long filiform tail (8.1 a.b.d.), spicules elongated and straight (4.4 a.b.d.), cephalate proximally and pointed distally, gubernaculum tubular, with dorsal apophysis. Micoletzkyia nanhaiensis sp. nov. is characterized by spicules slender and curved, 2.5 a.b.d. long, cephalous proximally and chapiter-shaped distally, and gubernaculum with relatively long dorsal apophysis. A key for all known species of Micoletzkyia is proposed.
