Cyclaspis similis Calman 1907

Diagnosis. Female. Carapace sparsely tuberculated, without pitting or reticulation, with quadrangular lateral depression bounded by ridges, bounding may be incomplete dorsally, corners not marked by large tubercles, ridges not standing away from carapace; 0.6 times as high as long; eyelobe with lenses; antennal notch present; anteroventral corner serrate. Pereonite 1 visible laterally, occasionally dorsally in ovigerous females. Pereonite 2 not produced dorsally tooth, paired dorsal crests present on all pereonites and to pleonite 5. Pleon with lateral articular pegs. Uropod peduncles shorter than pleonite 6; endopod slightly shorter than or equal to exopod length; endopod without setae; exopod with few plumose setae distally. Male. Carapace less arched than in female, ridges less pronounced, lateral depression smaller than in female. Pleon articular pegs less pronounced than in female.

Remarks. Cyclaspis similis is most similar to C. elegans . The carapace ornamentation is similar, in that both species have a lateral quadrangular depression bounded by ridges. However, in C. elegans the ornamentation is much stronger, with the ridges standing out away from the carapace and large tubercles marking the corners of the depression, while in C. similis the ridges are less strong, the depression may not be entirely bounded by ridges, and there are not large tubercles at the corners of the depression.