Pennella Oken 1816

Review of Pennella Oken, 1816

In this review, three basic categories of species validity are proposed: 1) Valid and substantiated. These established nine species have adequate original descriptions or redescriptions based on several specimens. They have been found and described on more than one occasion, from the same host species or types of hosts. The validity of all but the new species, P. benzi sp. nov., has been repeatedly suggested in the literature. 2) Species inquirendae. All six species in this category have acceptable (but often brief) original descriptions, with figures that portray the parasite. All show unique features which serve to distinguish them from other members of Pennella. However, the original reports are based on a single (adult) specimen and the parasite has not been reported or described since the initial record. Type (or other) specimens are not available or do not exist. 3) Unsubstantiated and invalid. This category contains 29 species for which there are very poor or no original descriptions (nomen nudum) and those which have been previously designated as synonyms of established species.

For each of the 15 species designated as valid or species inquirendae, the differentiating characters are presented. For size (length) listing for each species, the range is given (unless based on a single specimen) based on previous reports and recent examinations and is from the mature, ovigerous female (anterior end of cephalothorax to posterior end of abdomen). Information on the hosts and localities (where known) are listed. An assessment of the value of the original descriptions and figures, as well as the rational for considering the species as different from its congeners is discussed.