''Gymnobela bairdii'', common name Baird's turrid, is a species 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 e ...
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 ...
Raphitomidae
Raphitomidae is a family of small to medium-sized sea snails, marine gastropod mollusks in the superfamily Conoidea.Bouchet P. & Rocroi J.-P. (Ed.) (2005). "Classification and nomenclator of gastropod families". ''Malacologia'' 47(1-2). . 39 ...
.
Description
The length of the shell varies between 10 mm and 55 mm.
(Original description) The large, rather stout shell has a fusiform shape. It shows an elevated, acute, turreted
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 a ...
and eight or nine obtusely shouldered, angular
whorls. The
body whorl is large and somewhat inflated, with a broad, flattened or a slightly concave, sloping subsutural band, which is covered with distinct, strongly receding lines of growth and with more or less evident, raised, spiral cinguli and grooves. Below the subsutural band the whorls are obtusely angulated, but without a distinct carina. Commencing at the shoulder and extending a short distance below it are numerous oblique, not very elevated, longitudinal ribs, which fade
out before reaching the middle of the whorls. The whole surface of the whorls, including the ribs, is covered with conspicuous, raised, spiral cinguli, between which there are two or three smaller ones, separated by deep concave grooves of about the same breadth. The whole surface is covered by distinct, raised lines of growth. 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 oblong-ovate and is rather large. 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 wo ...
is nearly straight, somewhat prolonged, its inner edge forming a slight sigmoid curve. The
siphonal canal is short, broad, narrowed at the tip and not recurved. 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 sharp and thin. The posterior sinus is broad and rather deep, with regularly rounded margins, corresponding to the lines on the subsutural band. Below the shoulder the lip projects considerably forward and then is somewhat flattened and recedes gradually to the base of the short and broad siphonal canal. The whorls of the
protoconch are very small and generally eroded so far as to appear smooth. The shell is white or grayish white, without any distinct epidermis. The aperture is clear white. The animal is destitute of
operculum and eyes.
Distribution
''G. bairdii'' can be found off the North American coast, ranging from
New Jersey
New Jersey is a state in the Mid-Atlantic and Northeastern regions of the United States. It is bordered on the north and east by the state of New York; on the east, southeast, and south by the Atlantic Ocean; on the west by the Delaware ...
south to
Florida
Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...
, between depths of 1061 m and 4062 m.
[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. 668.]
References
* Figueira R.M. Andrade & Absalão R.S. (2012) ''Deep-water Raphitomidae (Mollusca, Gastropoda, Conoidea) from the Campos Basin, southeast Brazil.'' Zootaxa 3527: 1–27
External links
*
Verrill A. E. (1884). ''Second catalogue of mollusca recently added to the fauna of the New England Coast and the adjacent parts of the Atlantic, consisting mostly of deep sea species, with notes on others previously recorded.'' Transactions of the Connecticut Academy of Arts and Sciences, 6(1): 139-294, pl. 28-32Rosenberg, G.; Moretzsohn, F.; García, E. F. (2009). Gastropoda (Mollusca) of the Gulf of Mexico, Pp. 579–699 in: Felder, D.L. and D.K. Camp (eds.), Gulf of Mexico–Origins, Waters, and Biota. Texas A&M Press, College Station, Texas
{{DEFAULTSORT:Gymnobela Bairdii
bairdii
Gastropods described in 1884