former taxonomy:
Class: GASTROPODA  Cuvier, 1797
Subclass: OPISTHOBRANCHIA  Milne-Edwards, 1848
Order: SACOGLOSSA  von Ihering, 1876

on the recent taxonomy see WoRMS:
MolluscaBase eds. (2023). Julia  Gould, 1862. Accessed through:
World Register of Marine Species
at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=206683 on 2023-10-12
-