Protatlanta souleyeti
Encyclopedia
Protatlanta souleyeti is a species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...

 of sea snail
Sea snail
Sea snail is a common name for those snails that normally live in saltwater, marine gastropod molluscs....

, a holoplankton
Holoplankton
Holoplankton are organisms that are planktonic for their entire life cycle. Examples of holoplankton include some diatoms, radiolarians, some dinoflagellates, foraminifera, amphipods, krill, copepods, and salps.-Sources:Asexual Holoplankton:...

ic marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...

 gastropod mollusk in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...

 Atlantidae
Atlantidae
Atlantidae is a family of sea snails, holoplanktonic gastropod molluscs in the clade Littorinimorpha.According to taxonomy of the Gastropoda by Bouchet & Rocroi the family Atlantidae has no subfamilies.- Description :...

.

Protatlanta souleyeti is the type species on the genus Protatlanta. It is considered to be the only Recent species on the genus.

The specific name souleyeti is in honor of French malacologist Louis François Auguste Souleyet
Louis François Auguste Souleyet
Louis François Auguste Souleyet was a French zoologist, malacologist and naval surgeon.Souleyet was naturalist-surgeon on the voyage of La Bonite, which circumnavigated the globe between February 1836 and November 1837 under Auguste Nicolas Vaillant . In the Pacific he studied marine molluscs...

.

Description

The maximum recorded shell
Gastropod shell
The gastropod shell is a shell which is part of the body of a gastropod or snail, one kind of mollusc. The gastropod shell is an external skeleton or exoskeleton, which serves not only for muscle attachment, but also for protection from predators and from mechanical damage...

 length is 2 mm.

Some of the fossil specimens preserve a pinkish colour of the larval shells. The protoconch is naticoid in shape and has approximately 3¼ whorls. Most specimens have two thin spirals above the periphery, visible in apical view, and a third such spiral below the periphery, which separates the base of the protoconch and becomes covered by subsequent whorls. The described ornament can be fairly constant, but some specimens were found in which these three spirals are lacking. Richter (1968, p. 17, fig. 6c) described Recent larval shells from the Gulf of Naples
Gulf of Naples
The Gulf of Naples is a c. 15 km wide gulf located in the south western coast of Italy, . It opens to the west into the Mediterranean Sea. It is bordered on the north by the cities of Naples and Pozzuoli, on the east by Mount Vesuvius, and on the south by the Sorrentine Peninsula and the main...

 as smooth. For Recent material from near Hawaii, Seapy (1990, p. 114, fig. 4A-D) also stated that the first whorls are smooth. But Batten & Dumont (1976, figs. 39-41) and Richter & Seapy (1999, p. 633, fig. 5A) and Janssen (2007) have described two protoconch morphologies. On the teleoconch whorls, the peripheral belt on which the conchiolin
Conchiolin
Conchiolin and perlucin are complex proteins which are secreted by a mollusc's outer epithelium ....

 keel was attached is very clear. Growth lines are strongly bent backward on this belt, indicating the presence of a deep sinus on the apertural margin. A very faint spiral striation is visible all over the adult shell surface.

Distribution

The first fossil specimens of Protatlanta souleyeti from Cainozoic has been found from Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...

 in Anda, Pangasinan
Anda, Pangasinan
Anda is a 4th class island-municipality in the province of Pangasinan, Philippines. The people of Anda generally speak Bolinao. The island is near the Hundred Islands, a popular tourist destination for its caves and beaches....

, Luzon, Philippines in 2001 (published in 2007).
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