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n. pl.1.(Zool.) An order of Crustacea, including Nebalia and allied forms.
References in periodicals archive ?
Within the Malacostraca, the Leptostraca possess a pleon (abdomen) consisting of seven segments and a telson.
The formation of an embryonic anlage of a seventh pleonic ganglion that later fuses with the sixth ganglion has been reported from representatives of most highermalacostracan taxa including Leptostraca (Claus, 1888; Manton, 1928b, 1934), Hoplocarida (Shiino, 1942), Syncarida (Hickman, 1937), Mysidacea (Manton, 1928a, b), Tanaidacea (Scholl, 1963), and Isopoda (Stromberg, 1967).