''Calliclava aegina'' is a

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

sea snail Sea snails are slow-moving marine (ocean), marine gastropod Mollusca, molluscs, usually with visible external shells, such as whelk or abalone. They share the Taxonomic classification, taxonomic class Gastropoda with slugs, which are distinguishe ...

, a marine

gastropod Gastropods (), commonly known as slugs and snails, belong to a large Taxonomy (biology), taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, freshwater, and fro ...

mollusk Mollusca is a phylum of protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant species of molluscs are recognized, making it the second-largest animal phylum after Arthropoda. The ...

in the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

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 approx ...

Description

The length of the shell attains 13 mm, its diameter 4.8 mm. (Original description) The brownish shell is pale on the early whorls, with a whitish glaze and polished. The shell is acute, except for the apex of 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 " ...

, which is flattened. The protoconch is smooth and polished. It contains two

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). In nature File:Photograph and axial plane floral diagra ...

s, the second sharply keeled and passing gradually into 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 ...

of the subsequent 8½ whorls. The suture is strongly appressed behind the concave arcuately striated anal fasciole. The axial sculpture shows (on the

body whorl The body whorl is part of the morphology (biology), morphology of the gastropod shell, 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 ...

10) prominent protractive ribs extending from the fasciole to the succeeding suture 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. Spire ...

and somewhat over the periphery on the body whorl. These ribs are knob-like and prominent on the periphery and rapidly diminish forward. The incremental sculpture is faint. The spiral sculpture begins on the early whorls with about four faint striae which grow sharper on the later whorls which carry four or five grooves with wider flattish interspaces between the periphery and the succeeding suture, with on the later whorls sometimes one or two on the anal fasciole. On the body whorl there are 16 or more in all. The last rib on the body whorl is more swollen than the others and usually darker in color. The

aperture In optics, the aperture of an optical system (including a system consisting of a single lens) is the hole or opening that primarily limits light propagated through the system. More specifically, the entrance pupil as the front side image o ...

is narrow. The outer

lip The lips are a horizontal pair of soft appendages attached to the jaws and are the most visible part of the mouth of many animals, including humans. Mammal lips are soft, movable and serve to facilitate the ingestion of food (e.g. sucklin ...

is thin, sharp, produced, smooth internally with a deep rounded anal sulcus close to the suture with a heavy lump of callus on the side of the body. The inner lip has a rather thick callus with a raised edge extending to the end of the

columella Lucius Junius Moderatus Columella (, Arabic: ) was a prominent Roman writer on agriculture in the Roman Empire. His in twelve volumes has been completely preserved and forms an important source on Roman agriculture and ancient Roman cuisin ...

. 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 i ...

is short, wide, deeply cut, with a small keel bordering the posterior edge of the siphonal fasciole. The operculum is dark brown.Dall (1919) Descriptions of new species of Mollusca from the North Pacific Ocean; Proceedings of the U.S. National Museum, vol. 56 (1920)
(described as ''Elaeocyma aegina'')

Distribution

This marine species was found off Agua Verde Bay,

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

, Western

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

References

External links

* {{DEFAULTSORT:Calliclava Aegina

aegina Aegina (; ; ) is one of the Saronic Islands of Greece in the Saronic Gulf, from Athens. Tradition derives the name from Aegina (mythology), Aegina, the mother of the mythological hero Aeacus, who was born on the island and became its king. ...

Gastropods described in 1919