''Cryptogemma periscelida'', common name the Atlantic gem turrid, 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 ...

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

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 ...

Turridae Turridae is a Taxonomy (biology), taxonomic family (biology), family name for a number of predatory sea snails, Marine (ocean), marine gastropod mollusks in the superfamily Conoidea.MolluscaBase (2018). Turridae H. Adams & A. Adams, 1853 (1838). ...

, the turrids.MolluscaBase eds. (2020). MolluscaBase. Cryptogemma periscelida (Dall, 1889). Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=1425549 on 2020-10-16

Description

The length of the shell varies between 25 mm and 50 mm. (Original description by W.H. Dall) The stout shell has a fusiform shape. It is covered with a straw-colored epidermis. It is elaborately sculptured and contains 10

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, exclusive 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 " ...

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 ...

consists of: * (1) a cord at first rounded and irregularly constricted at short intervals, later flattened with numerous transverse waves and indentations. This band becomes gradually wider, has two small grooves along its center, and at the sides, especially the sutural side, it overhangs the channels on each side of it. From the first this band conceals the suture, toward the end of 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 ...

it becomes less prominent and descends slightly. *(2) a broad elevated band grooved centrally and covered with twin nodules in pairs one above the other, which on the later whorls are somewhat reniform. This band represents the fasciole or pathway of the square-cut anal notch. *(3) in the channel between the two last are two small, elevated, rounded nodulous cords. *(4) in front of the fasciole and on the base of the body whorl are four or five strong spirals, and between these and in front of them 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 i ...

are numerous smaller ones, all crossed and roughened by the transverse ridges of growth. One or two of these spirals are visible on the whorl before the last, the earlier ones not showing any of the basal spirals. Transverse sculpture consists of coarse elevated incremental lines more or less visible over the whole shell. 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 rather wide The siphonal canal is narrow and slightly curved. 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 ...

shows a deep notch squared at the bottom, then strongly arched forward, later contracted for the siphonal canal. The columellar margin is simple and sharp. The inner lip is white, smooth, simple and slightly excavated . Inside the outer lip are six or eight strong lirae falling short of the margin. 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 ...

is nearly straight, attenuated and twisted in front, making the end of the siphonal canal flare a little. There is no umbilical trace. This species is one of the most remarkable and elegant of any from the deeper waters. It belongs to the group of which ''Pleurotoma speciosa'' Reeve forms a member, by its sculpture, though whether the nucleus would agree with that species is uncertain. At present our judgment on such subdivisions as ''Gemmula'' Weinkauff, founded on nuclear characters, must be held suspended. So far as our knowledge goes, nuclear characters have little absolute systematic value in this group, and their relative value remains to be determined.

Distribution

''C. periscelida'' can be found in Atlantic waters, ranging from the coast of

North Carolina North Carolina ( ) is a U.S. state, state in the Southeastern United States, Southeastern region of the United States. It is bordered by Virginia to the north, the Atlantic Ocean to the east, South Carolina to the south, Georgia (U.S. stat ...

south to

Colombia Colombia, officially the Republic of Colombia, is a country primarily located in South America with Insular region of Colombia, insular regions in North America. The Colombian mainland is bordered by the Caribbean Sea to the north, Venezuel ...

.Tunnell, John W., Jr., Felder, Darryl L., & Earle, Sylvia A., eds. ''Gulf of Mexico Origin, Waters, and Biota, Volume 1: Biodiversity.'' Texas A&M University Press, 2009. 669.

References

External links

Dall W.H. 1889. Reports on the results of dredging, under the supervision of Alexander Agassiz, in the Gulf of Mexico (1877-78) and in the Caribbean Sea (1879-80), by the U.S. Coast Survey Steamer "Blake", Lieut.-Commander C.D. Sigsbee, U.S.N., and Commander J.R. Bartlett, U.S.N., commanding. XXIX. Report on the Mollusca. Part 2, Gastropoda and Scaphopoda. Bulletin of the Museum of Comparative Zoölogy at Harvard College, 18: 1-492, pls. 10-40.

Zaharias P., Kantor Y.I., Fedosov A.E., Criscione F., Hallan A., Kano Y., Bardin J. & Puillandre N. (2020). Just the once will not hurt: DNA suggests species lumping over two oceans in deep-sea snails (Cryptogemma). Zoological Journal of the Linnean Society. DOI: 10.1093/zoolinnean/zlaa010/5802562
* {{DEFAULTSORT:Cryptogemma Periscelida periscelida Gastropods described in 1889