''Compsodrillia alcestis'' 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 ...

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 Pseudomelatominae ...

, the turrids and allies.

Description

The length of the shell attains 43.5 mm, its diameter 15.3 mm. (Original description) The slender shell is acute and pale yellowish brown. It contains (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), about ten

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 strongly appressed with a prominent cord (afterwards broadening into a band) in front of it. The siphonal fasciole is constricted; with only arcuate striation. The

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 two or three strong cords, swollen where they override the ribs, these are prominent on the periphery. On the later whorls the peripheral cord becomes an undulated keel and the interspaces are closely spirally striate. On the body whorl in front of the keel are about a dozen major threads with wide spirally striate interspaces. The axial sculpture of (on the body whorl seven) peripheral waves, rather than ribs, overridden by the spirals, the incremental lines inconspicuous. 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 slightly removed from the suture, distinct, with a small subsutural

callus A callus is an area of thickened and sometimes hardened skin that forms as a response to repeated friction, pressure, or other irritation. Since repeated contact is required, calluses are most often found on the feet and hands, but they may o ...

. 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 moderately produced, sharp edged, slightly crenulate by the spiral sculpture, smooth within. The inner lip shows a moderate layer of callus, with slightly raised outer edge which is continued over 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 ...

and on 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 separated from the feeble siphonal fasciole by a narrow chin. The siphonal canal is short, wide and slightly recurved.Dall (1919) Descriptions of new species of Mollusca from the North Pacific Ocean; Proceedings of the U.S. National Museum, vol. 56 (1920)

Distribution

This marine species occurs from the

Gulf of California The Gulf of California ( es, Golfo de California), also known as the Sea of Cortés (''Mar de Cortés'') or Sea of Cortez, or less commonly as the Vermilion Sea (''Mar Bermejo''), is a marginal sea of the Pacific Ocean that separates the Baja C ...

to Colombia

References

External links

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
* * {{DEFAULTSORT:Compsodrillia Alcestis

alcestis Alcestis (; Ancient Greek: Ἄλκηστις, ') or Alceste, was a princess in Greek mythology, known for her love of her husband. Her life story was told by pseudo-Apollodorus in his '' Bibliotheca'', and a version of her death and return fr ...

Gastropods described in 1919