A preliminary inquiry into an Asian topsy‐turvy Dom, Allobathynella with the description of a new species from South Korea and redescription of A. japonica (Crustacea, Syncarida, Parabathynellidae)

Allobathynella japonica Morimoto and Miura, 1957 and a new species of Allobathynella from South Korea are described with detailed descriptions of each male thoracopod VIII. The new species, A. shinjongieei sp. nov., differs from its congeners in having a median seta on the inner margin of the fifth antennular segment, ten spines on the uropodal sympod and in the absence of an epipod in thoracopods I–III. Allobathynella shinjongieei belongs to the mirabilis group which otherwise includes A. japonica, A. mirabilis and A. coreana. The mirabilis group is assumed to be a distinct taxonomic unit. The supporting characters for this assumption are the bell‐formed male thoracopod VIII attaching perpendicularly to the body which has a flat and round epipod, the absence of the mandibular proximal tooth and the absence of the seta on the pleotelson.