''Knefastia polygona'' is an extinct
species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of
sea snail
Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...
, a marine
gastropod
The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda ().
This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...
mollusk
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...
in the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Pseudomelatomidae
Pseudomelatomidae is a family of predatory sea snails, marine gastropods included in the superfamily Conoidea (previously Conacea) and part of the Neogastropoda ( Bouchet & Rocroi, 2005).
In 1995 Kantor elevated the subfamily Pseudomelatomina ...
, the turrids and allies.
Description
The length of the shell attains 20 mm.
Distribution
This extinct marine species was found in
Eocene
The Eocene ( ) Epoch is a geological epoch (geology), epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period (geology), Period in the modern Cenozoic Era (geology), Era. The name ''Eocene' ...
strata in the Paris basin, France.
References
* Deshayes, G. P., 1834–1835, Description des coquilles fossiles des environs de Paris, t. II, fasc. 5 et 6, in-4°, Paris, 1834–1835.
* Cossmann (M.) & Pissarro (G.), 1913 Iconographie complète des coquilles fossiles de l'Éocène des environs de Paris, t. 2, p. pp. 46–65
* Le Renard (J.) & Pacaud (J.-M.), 1995 Révision des Mollusques paléogènes du Bassin de Paris. 2 - Liste des références primaires des espèces. Cossmanniana, t. 3, vol. 3, pp. 65–132
* Caze (B.), Merle (D.), Saint Martin (J.-P.) & Pacaud (J.-M.), 2012 Les mollusques éocènes se dévoilent sous ultraviolets. Fossiles. Revue française de paléontologie, t. hors série n° 3, pp. 15–56
External links
MNHN, Paris: Knefastia polygona
polygona
''Polygona'' is a genus of sea snails, marine gastropod mollusks in the family Fasciolariidae, the spindle snails, the tulip snails and their allies.
Species
Species within the genus ''Polygona'' include:
* '' Polygona abbotti'' (Snyder, 2003)
...
Gastropods described in 1834
{{paleo-Pseudomelatomidae-stub