Rostanga is a genus of sea slugs in the family Discodorididae. Some sources, such as The Sea Slug Forum still classify Rostanga in the family Dorididae.
Omalogyridae are a family of minute and microscopic sea snails, marine gastropod molluscs or micromolluscs in the informal group Lower Heterobranchia. Adult shells are usually smaller than 1 millimeter.
Omalogyra is a genus of minute marine gastropod molluscs in the family Omalogyridae.
Sigmurethra is a taxonomic category of air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs. This is an informal group which includes most land snails and slugs.
Pleurobranchus is a genus of sea slugs, specifically side-gill slugs, marine gastropod mollusc in the family Pleurobranchidae.
Bactrocythara agachada is a species of sea snail, a marine gastropod mollusk in the family Mangeliidae.
Pseudorbis is a genus of sea snails, marine gastropod mollusks in the family Skeneidae.
Eatonina is a genus of minute sea snails, marine gastropod mollusks in the family Cingulopsidae.
Crisilla is a genus of minute sea snails, marine gastropod mollusks or micromollusks in the family Rissoidae.
Obtusella is a genus of minute sea snails, marine gastropod mollusks or micromollusks in the family Rissoidae.
Zebina is a genus of minute sea snails, marine gastropod mollusks or micromollusks in the family Zebinidae.
Adeuomphalus is a genus of sea snails, marine gastropod molluscs unassigned to family within the superfamily Seguenzioidea.
Facelina is a genus of sea slug, an aeolid nudibranch in the family Facelinidae.
Berthellina is a genus of sea slugs, marine gastropod molluscs in the family Pleurobranchidae.
Cima is a genus of minute sea snails, marine gastropod molluscs in the family Cimidae.
Hyalogyra is a genus of sea snails, marine gastropod mollusks in the family Hyalogyrinidae.
Retrotortina is a genus of very minute sea snails, marine gastropod molluscs or micromollusks in the family Omalogyridae.
Pseudotorinia is a genus of sea snails, marine gastropod mollusks in the family Architectonicidae, the staircase shells or sundials.
After excluding groups not related, the informal group Sigmurethra has become the suborder Helicina, with the following infraorders and a collection of families with no superfamily：
Amonovula is a monotypic genus of marine gastropod molluscs in the family Ovulidae, the ovulids, cowry allies or false cowries
