fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...
species
A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
of small
sea snail
Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...
gastropod
Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda ().
This class comprises snails and slugs from saltwater, freshwater, and fro ...
mollusk
Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...
in the
family
Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
Liotiidae
Liotiidae is a family of small sea snails, marine gastropod mollusks in the clade Vetigastropoda (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).Gofas, S. (2013). Liotiidae Gray, 1850. Accessed through: World Register of ...
.McLean New species of recent and fossil West American aspidobranch gastropods; The Veliger v.7 # 2(1964-1965) /ref>
Description
The height of the shell attains 20 mm, its diameter 25 mm. The narrowly umbilicated shell contains 4
whorl
A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs).
In nature
File:Photograph and axial plane floral diagra ...
s with distinct sutures and a projecting peripheral keel. The oblique aperture is circular. Its color is chalky white. This fossil species shows some similarities with ''
Macrarene coronadoensis
''Macrarene'' is a genus of small sea snails, marine gastropod mollusks in the family Liotiidae within the superfamily Trochoidea, the top snails, turban snails and their allies.Gofas, S.; Rosenberg, G. (2012). ''Macrarene'' Hertlein & Strong, ...
'' and ''
Macrarene californica
''Macrarene californica'', common name the Californian liotia, is a species of sea snail, a marine gastropod mollusk in the family Liotiidae.Rosenberg, G. (2012). ''Macrarene californica'' (Dall, 1908). Accessed through: World Register of Marin ...
''.
Distribution
This species is known only as a fossil. It is found in the
San Diego Formation
The San Diego Formation is a geological formation in southwestern San Diego County, California, United States, and northwestern Baja California, Mexico.
Geology
It is a coastal transitional marine and non-marine pebble and cobble conglomerat ...
, California, and dates from the
Pliocene
The Pliocene ( ; also Pleiocene) is the epoch (geology), epoch in the geologic time scale that extends from 5.33 to 2.58diegensis
Gastropods described in 1964