''Miraclathurella amica'' is an extinct

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), ...

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 ...

, a marine

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 ...

Pseudomelatomidae Pseudomelatomidae is a family (biology), family of predatory sea snails, marine gastropods included in the superfamily Conoidea (previously Conacea) and part of the Neogastropoda (Taxonomy of the Gastropoda (Bouchet & Rocroi, 2005), Bouchet & Ro ...

, the turrids and allies.

Description

The length of the shell is 16.3 mm, its dialmeter 5.25 mm. (Original description) This extinct species resembles ''

Miraclathurella gracilis ''Miraclathurella gracilis'' is an extinct species of sea snail, a marine gastropod mollusk in the family Pseudomelatomidae, the turrids and allies. Description The length of the shell attains 28.5 mm, its diameter 7.5 mm. On the pen ...

'' but it is less slender and the

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 are shorter and revolve less obliquely. It has the same number of axial ribs and spiral threads but, as they are relatively larger, they are much more crowded than in ''M. gracilis''. The fine spiral lines between the prominent raised threads are very minute. The lip

varix A varix (: varices) is an abnormally dilated blood vessel with a tortuous course. Varices usually occur in the venous system, but may also occur in arterial or lymphatic vessels. Examples of varices include: * Varicose veins, large tortuous veins ...

is noticeably larger and the

aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

is wider. The callous nodule on the body next to the sinus is much larger than in ''M. gracilis''.Pilsbry & Johnson (1917), New Mollusca from the Santo Domingan Oligocene, Proceedings of the Academy of Natural Sciences of Philadelphia, 1917
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Distribution

Fossils of this species were found in

Oligocene The Oligocene ( ) is a geologic epoch (geology), epoch of the Paleogene Geologic time scale, Period that extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that defin ...

strata in

Santo Domingo Santo Domingo, formerly known as Santo Domingo de Guzmán, is the capital and largest city of the Dominican Republic and the List of metropolitan areas in the Caribbean, largest metropolitan area in the Caribbean by population. the Distrito Na ...

Dominican Republic The Dominican Republic is a country located on the island of Hispaniola in the Greater Antilles of the Caribbean Sea in the Atlantic Ocean, North Atlantic Ocean. It shares a Maritime boundary, maritime border with Puerto Rico to the east and ...

References

* W. P. Woodring. 1928. ''Miocene Molluscs from Bowden, Jamaica. Part 2: Gastropods and discussion of results.'' Contributions to the Geology and Palaeontology of the West Indies. * B. Landau and C. Marques da Silva. 2010. ''Early Pliocene gastropods of Cubagua, Venezuela: Taxonomy, palaeobiogeography and ecostratigraphy''. Palaeontos 19:1-221

External links

Fossilworks: ''Miraclathurella amica''
{{DEFAULTSORT:Miraclathurella amica amica Gastropods described in 1917