Marginellidae

Taxonomy

The higher classification of the family Marginellidae has long been in a state of confusion. Many popular works still treat all members of this family under the single genus Marginella, basing them primarily on superficial similarities of the shell.

The confusion over the classification stems from the fact that the earlier classifications were based rather crudely on shell characters. Although many good differential shell characters do exist within this group, those characters were generally misinterpreted or not recognized as significant. Such information as did exist on the radulae and the external anatomy of the living animals was widely scattered in the scientific literature, and internal anatomical descriptions were not available until fairly recently.

Shell description

The shell of Marginellidae is usually small, but varies in different species from minute to medium-sized. The external color of the shell can be white, cream, yellow, orange, red, or brown, and can be uniformly colored, or patterned in various ways. The protoconch is paucispiral. The lip of the shell is thickened, and can be smooth or denticulate. An external varix may be present or absent, a siphonal notch may be present or absent. The columella may have 2-6 plications. The operculum is absent in this family.

Genera

Abbreviations and conventions:

In the systematic, the following sequence is used for each generic synonym:

Marginellidae Fleming, 1828:328

Subfamily Granulininae: This subfamily was originally placed in family Cystiscidae by Coovert & Coovert (1995) but placed back in Marginellidae, following La Perna (1999) and based on the morphology of living animals.

Subfamily MARGINELLONINAE Coan 1965:186,191