''Antiplanes amphitrite'' 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 ...

,. These is one subspecies: ''Antiplanes amphitrite beroë'' Dall, 1919: it is larger (height 19 mm, diameter 9 mm.), with the suture appressed, the fasciole close to it, and bearing three or four spiral grooves

Description

The length of the shell attains 13.5 mm, its diameter 6 mm. (Original description) The white shell is covered with a pale olivaceous

periostracum The periostracum ( ) is a thin, organic coating (or "skin") that is the outermost layer of the shell of many shelled animals, including molluscs and brachiopods. Among molluscs, it is primarily seen in snails and clams, i.e. in gastropods a ...

. It contains five or more well-rounded whorls exclusive of the (lost)

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 ...

. These show a rounded shoulder and a distinct but not appressed suture. The 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 ...

consists of, on the

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 ...

, obscure nodulations at the shoulder (about 15 on the penultimate whorl) which do not form ribs and are absent from the body whorl. The incremental lines are fine but obscure. Beside these there are minute, anteriorly obliquely retractive lines somewhat microscopically reticulated by the lines of growth.tTere is no spiral sculpture except on some specimens a few obsolete lines on the base. The anal sulcus is shallow, slightly removed from the suture. The fasciole is lightly impressed on the body whorl. 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 outer lip is thin, sharp and arcuately produced. The inner lip is erased. 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 white, solid straight, anteriorly obliquely attenuated. 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 wide, straight and distinct Dall (1919) Descriptions of new species of Mollusca from the North Pacific Ocean; Proceedings of the U.S. National Museum, vol. 56 pp.1–86, 24 pls (1920)

Distribution

The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of seve ...

was found off

Santa Barbara Island Santa Barbara Island (Spanish: ''Isla de Santa Bárbara''; Tongva: ''Tchunashngna'') is a small island of the Channel Islands archipelago in Southern California. It is protected within Channel Islands National Park, and its marine ecosyste ...

, California, USA.

References

External links

* {{DEFAULTSORT:Antiplanes Amphitrite

amphitrite In ancient Greek mythology, Amphitrite (; grc-gre, Ἀμφιτρίτη, Amphitrítē) was the goddess of the sea, the queen of the sea, and the wife of Poseidon. She was a daughter of Nereus and Doris (or Oceanus and Tethys).Roman, L., & Rom ...

Gastropods described in 1919