Discrimination and phylogeny of solenogaster species through the morphology of hard parts (Mollusca, Aplacophora, Neomeniomorpha).

Ten species in five genera and three families from continental shelf and deep-sea collections of neomenioid Aplacophora (Mollusca) are described, emphasizing external anatomy and hard parts--body shape, radula, epidermal spicules, and copulatory spicules--as well as the reproductive system. One genus and seven species are new: Plawenia n.g., Plawenia sphaera, P. argentinensis, Dorymenia tortilis, Eleutheromenia bassensis, E. mimus, Kruppomenia levis, and K. delta. Also included are redescriptions of three published species, emphasizing hard parts for comparisons with the new species and genus: Dorymenia sarsii (Koren & Danielssen), Simrothiella margaritacea (Koren & Danielssen), and Plawenia schizoradulata (Salvini-Plawen). A cladistic analysis of species described here demonstrates the usefulness of hard parts for phylogeny. Specimens came from collections made in the southwest Pacific and the southwest and northeast Atlantic.