Cyclaspis levis Thomson 1892
Synonymy. Cyclaspis calmani in Hale 1944.
Diagnosis. Female. Carapace finely pitted, without ridges; 0.5 as high as long; eyelobe with distinct lenses; antennal notch present; anteroventral corner smooth. Pereonite 1 visible from side only. Pereonite 2 not produced dorsally. Pleon with lateral articular pegs, dorsal keel and lateral keel. Uropod peduncles equal or slightly longer than pleonite 6; endopod shorter than exopod; endopod with 4 stout setae medially; exopod with plumose setae and short terminal seta. Male. Carapace less arched than in female. Pereonite 1 concealed entirely. Uropod peduncles distinctly longer than pleonite 6; endopod slightly longer than exopod. Appendages with more setae than in female.
Remarks. See Jones (1963, p.30) for a synopsis and discussion of the poor original description, and the current understanding of this species. The most similar species in the New Zealand fauna is Cyclaspis petrescui, which also has a smooth carapace and distinct lenses in the eyelobe. However, in C. petrescui, the carapace is finely reticulated, 0.7 times as high as long, the pleon has only a dorsal keel, the uropod peduncles are distinctly shorter than pleonite 6 in the female, and there are fewer setae on the uropod rami. In comparison, in C. levis the carapace is finely pitted, 0.5 times as high as long, the pleon has a dorsal keel and lateral keel, the uropod peduncles are equal to or longer than pleonite 6 in the female, and there are more setae on the uropod rami.