Diacria quadridentata forma danae from the Atlantic

A sediment sample, collected near Frederikstad, St. Croix in the Caribbean (17°N 65°W, depth 500 fathoms), presented to the Zoological Museum at Amsterdam by Dr. J. Hofker, proved to consist of five pteropod species. These are Cavolinia inflexa (Lesueur, 1813) forma inflexa (Lesueur, 1813) (32 specimens), Cavolinia longirostris (Blainville, 1821) forma longirostris (Blainville, 1821) (287), Cavolinia uncinata (Rang, 1829) forma uncinata (Rang, 1829) (11), Diacria trispinosa (Blainville, 1821) forma trispinosa (Blainville, 1821) (30), Diacria trispinosa (Blainville, 1821) forma major (Boas, 1886) (2), and Diacria quadridentata (Blainville, 1821) forma danae Van der Spoel, 1968 (29) (fig. 1), the last of which is new for the Atlantic Ocean. Diacria quadridentata forma danae was originally described from the Indian Ocean at 2°57’S 99°36’E. For a description of the forma one is referred to Van der Spoel (1968). As the material from the Caribbean provides valuable meristic data to distinguish the forma danae from the other formae of Diacria quadridentata a graph is given here based on Van der Spoel (1968, fig. 4) and data from the Caribbean material (fig. 2). The sample proves that the forma danae is not restricted to the Indian Ocean. Like the other formae of D. quadridentata and also those of D. trispinosa it is not geographically separated from the other formae of D. quadridentata, and also not restricted to one ocean only.