Bostrycapulus
Bostrycapulus, commonly known as the spiny slipper snails, is a genus of sea snails, marine gastropod mollusks in the family Calyptraeidae, the slipper snails, cup-and-saucer snails and hat snails. Before 2005, the snails in this genus were all thought to belong to one species, which was known as "Crepidula aculeata", the spiny slipper snail. However, morphological and DNA sequence data show that the spiny slipper snails are a monophyletic group that is more closely related to "Crepipatella" than it is to "Crepidula". Taxonomy. Taxonomic history. All of the species within the genus" Bostrycapulus" were previously assigned to  a single species, "Crepidula aculeata". However, molecular phylogenetic and anatomical work have shown them to be a separate monophyletic grouping or clade, which has elevated them to the genus status. DNA sequence data has also been used in combination with embryological observations to distinguish 8 species. Species. Species within the genus "Bostrycapulus" include: