''Teretia megalembryon'' is a

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 ...

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 ...

Raphitomidae Raphitomidae is a family of small to medium-sized sea snails, marine gastropod mollusks in the superfamily Conoidea.Bouchet P. & Rocroi J.-P. (Ed.) (2005). "Classification and nomenclator of gastropod families". ''Malacologia'' 47(1-2). . 39 ...

.MolluscaBase (2019). MolluscaBase. Teretia megalembryon (Dautzenberg & Fischer, 1896). Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=1391764 on 2019-12-06

Description

The length of the shell attains 3 mm. The minute, solid shell is whitish, except for the yellowish brown protoconch. The shell consists of 7 convex

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). Whorls in nature File:Photograph and axial plane floral ...

s, including 4 whorls in the

protoconch A protoconch (meaning first or earliest or original shell) is an embryonic or larval shell which occurs in some classes of molluscs, e.g., the initial chamber of an ammonite or the larval shell of a gastropod. In older texts it is also called ...

. The suture is distinct, constricted, with a fringe of minute axial wrinkles on the fasciole in front of it. There are many well-developed growth lines. There is no other axial

sculpture Sculpture is the branch of the visual arts that operates in three dimensions. Sculpture is the three-dimensional art work which is physically presented in the dimensions of height, width and depth. It is one of the plastic arts. Durable sc ...

except faint incremental lines. The spiral sculpture consists of (on the penultimate whorl 6 and on the

body whorl The body whorl is part of the morphology of the shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the b ...

about 10) fine, equal and equally distributed low threads with narrower interspaces, covering the whole shell except the anal fasciole. The

aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and focal length of an optical system determine the cone angle of a bundle of rays that come to a focus in the image plane. An opt ...

is ample, hardly differentiated from the short

siphonal canal The siphonal canal is an anatomical feature of the shells of certain groups of sea snails within the clade Neogastropoda. Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water is ...

. The

anal sulcus The anal sulcus, also called the anal sinus or anal canal, in Gastropods is a notch, a shelly tube at the top of the aperture In optics, an aperture is a hole or an opening through which light travels. More specifically, the aperture and fo ...

is wide and rather deep. The sharp outer

lip The lips are the visible body part at the mouth of many animals, including humans. Lips are soft, movable, and serve as the opening for food intake and in the articulation of sound and speech. Human lips are a tactile sensory organ, and can be ...

is prominently arcuate. The almost vertical

columella Lucius Junius Moderatus Columella (; Arabic: , 4 – ) was a prominent writer on agriculture in the Roman Empire. His ' in twelve volumes has been completely preserved and forms an important source on Roman agriculture, together with the wo ...

is short, twisted, strong. The axis is minutely pervious.''Small shells from dredgings off the southeast coast of the United states by the United States Fisheries Steamer "Albatross", in 1885 and 1886''. Proceedings of the United States National Museum, 70(18): 1-134
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Distribution

This species occurs in the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

off the

Azores ) , motto =( en, "Rather die free than subjected in peace") , anthem= ( en, "Anthem of the Azores") , image_map=Locator_map_of_Azores_in_EU.svg , map_alt=Location of the Azores within the European Union , map_caption=Location of the Azores wi ...

and off

Georgia Georgia most commonly refers to: * Georgia (country), a country in the Caucasus region of Eurasia * Georgia (U.S. state), a state in the Southeast United States Georgia may also refer to: Places Historical states and entities * Related to the ...

, USA.

References

* Beu, A.G. 2011 ''Marine Molluscs of oxygen isotope stages of the last 2 million years in New Zealand. Part 4. Gastropoda (Ptenoglossa, Neogastropoda, Heterobranchia).'' Journal of the Royal Society of New Zealand 41, 1–153

External links

*
Dautzenberg P. & Fischer H. (1896). Dragages effectués par l'Hirondelle et par la Princesse Alice 1888-1895. 1. Mollusques Gastéropodes. Mémoires de la Société Zoologique de France. 9: 395-498, pl. 15-22

Dall W. H. (1927). Small shells from dredgings off the southeast coast of the United states by the United States Fisheries Steamer "Albatross", in 1885 and 1886. Proceedings of the United States National Museum, 70(18): 1-134

Ortega, J.; Gofas, S. (2019). The unknown bathyal of the Canaries: new species and new records of deep-sea Mollusca. Zoosystema.41(26): 513-551

Serge GOFAS, Ángel A. LUQUE, Joan Daniel OLIVER,José TEMPLADO & Alberto SERRA (2021) - The Mollusca of Galicia Bank (NE Atlantic Ocean); European Journal of Taxonomy 785: 1–114
{{DEFAULTSORT:Teretia Megalembryon megalembryon Gastropods described in 1896