''Cruziturricula arcuata'' is a

species In biology, a species is the basic unit of Taxonomy (biology), 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 ...

of sea snail, a marine gastropod

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 es ...

in the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Drilliidae The Drilliidae are a taxonomic family of small predatory sea snails with high-spired shells. They are classified as marine gastropod mollusks in the superfamily Conoidea. This family has no subfamilies. It consists of about 30 genera and approxi ...

.WoRMS (2015). Cruziturricula arcuata (Reeve, 1843). In: MolluscaBase (2015). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=433446 on 2016-08-20 It is the only known species within the genus ''Cruziturricula''.

Description

The designation ''Pleurotoma arcuata'' Reeve, 1843 was poorly defined. It was accepted by Olsson as ''Cruziturricula panthea'' (Original description as ''Turricula (Surcula) panthea'' ) The solid shell is acute and has a fusiform shape It is, white or cream, with pale brown blotches between the ribs (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 calle ...

lost). The high

spire A spire is a tall, slender, pointed structure on top of a roof of a building or tower, especially at the summit of church steeples. A spire may have a square, circular, or polygonal plan, with a roughly conical or pyramidal shape. Spires are ...

contains about 14

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 flo ...

s. The suture is closely appressed, obscure with a rounded thread in front of it. The anal fasciole is close to the suture slightly depressed, spirally threaded, arcuately striated. The spiral

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 ...

on the early whorls consists of a peripheral keel with one strong thread behind it. The rest of the surface is finely closely spirally threaded. The last three or four whorls are peripherally waved with narrower interspaces over which the keel and thread are a little swollen, the fine threading continuing. The space in front of the keel on the body whorl with about 25 strong cords shows wider interspaces. 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 ...

is narrow. 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 distinct, without a subsutural callus. The 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 produced, thin and smooth inside. The inner lip shows a thin wash of enamel. The

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 ...

is straight. The

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 long, narrow, with no siphonal fasciole or recurvation.W.H. Dall (1919) .Descriptions of new species of Mollusca from the North Pacific Ocean in the collection of the United States National Museum; Proceedings of the United States National Museum v. 56 (1920)
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Distribution

This species occurs in the

Bay of Panama The Panama Bay ( es, Bahia de Panamá) is a large body of water off the coast of southern Panama, at . It is a part of the greater Gulf of Panama. Pollution Problems The Panama Bay is considered to be in an eutrophic state by the World Resources ...

. As a fossil it was found in the

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recent" ...

strata of

Peru , image_flag = Flag of Peru.svg , image_coat = Escudo nacional del Perú.svg , other_symbol = Great Seal of the State , other_symbol_type = Seal (emblem), National seal , national_motto = "Fi ...

References

Olsson, Axel A. "Biological Results of the University of Miami Deep-Sea Expeditions. 77. Mollusks from the Gulf of Panama Collected by R/V John Elliott Pillsbury, 1967." Bulletin of Marine Science 21.1 (1971): 35–92

External links

* {{DEFAULTSORT:Cruziturricula Arcuata arcuata Gastropods described in 1843