Bjørnberg, 1980
Females: P4 Exp2 lacking leaf-like spines. More characters can be accessed by backtracking the key:
Page 704
It is very difficult to distinguish between Paracalanus aculeatus, Paracalanus campaneri and Paracalanus denudatus. Bjørnberg (1980) refers to the difference in the shape of the receptaculum seminis in P. campaneri and P. aculeatus as the main difference between these two species.
Males: Unknown.