''Agathistoma viridulum'' is a

species In biology, a species is the basic unit of 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 the appropriate s ...

sea snail Sea snail is a common name for slow-moving marine gastropod molluscs, usually with visible external shells, such as whelk or abalone. They share the taxonomic class Gastropoda with slugs, which are distinguished from snails primarily by the ...

, a marine

gastropod The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...

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 Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

Tegulidae Tegulidae is a family of small to large sea snails, marine gastropod mollusks in the superfamily Trochoidea (according to the taxonomy of the Gastropoda by Bouchet & Rocroi, 2005).Bouchet, P. (2013). Tegulidae Kuroda, Habe & Oyama, 1971. Access ...

.MolluscaBase eds. (2022). MolluscaBase. Agathistoma viridulum (Gmelin, 1791). Accessed through: World Register of Marine Species at: https://www.marinespecies.org/aphia.php?p=taxdetails&id=1548543 on 2022-04-24

Description

The size of the shell varies between 13 mm and 30 mm. The solid, umbilicate shell has a conoida shape. Its color is whitish-grayish or greenish, radiately striped above with crimson or rich brown, beneath spotted or radiately striped with the same color. The short

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 ...

is rather obtuse. The six

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 floral ...

s are convex, encircled by spiral lirae which are more or less beaded upon the upper surface, the interstices between them minutely spirally striated. On the penultimate whorl they number about six. Below the periphery the lirae are finer, closer, and nearly smooth. The

body whorl The body whorl is part of the morphology of the 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. In gastropods In gastropods, the b ...

is obtusely angulate or rounded at the periphery. The base of the shell is rather flattened, somewhat concave around the umbilicus, and generally eroded in front of 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 opt ...

. The aperture is oblique. 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 ...

beveled to an acute edge, which is usually margined with green and is sulcated or crenulated, the furrows corresponding to the lirae of the outer surface. The pearly throat is also more or less sulcate. The arcuate

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 expanded above in a bright green callus which partly surrounds the umbilicus, at its base green, bearing a tubercular tooth, followed by several smaller ones. The basal margin is smooth or denticulate within. The umbilicus is wide and deep, white or greenish within.Tryon (1889), Manual of Conchology XI, Academy of Natural Sciences, Philadelphia
(described as ''Chlorostoma viridulum'')

Distribution

This species occurs in the Caribbean Sea off

Colombia Colombia (, ; ), officially the Republic of Colombia, is a country in South America with insular regions in North America—near Nicaragua's Caribbean coast—as well as in the Pacific Ocean. The Colombian mainland is bordered by the Car ...

Costa Rica Costa Rica (, ; ; literally "Rich Coast"), officially the Republic of Costa Rica ( es, República de Costa Rica), is a country in the Central American region of North America, bordered by Nicaragua to the north, the Caribbean Sea to the no ...

Panama Panama ( , ; es, link=no, Panamá ), officially the Republic of Panama ( es, República de Panamá), is a transcontinental country spanning the southern part of North America and the northern part of South America. It is bordered by Cos ...

and

Venezuela Venezuela (; ), officially the Bolivarian Republic of Venezuela ( es, link=no, República Bolivariana de Venezuela), is a country on the northern coast of South America, consisting of a continental landmass and many islands and islets in th ...

; in the Atlantic of

Brazil Brazil ( pt, Brasil; ), officially the Federative Republic of Brazil (Portuguese: ), is the largest country in both South America and Latin America. At and with over 217 million people, Brazil is the world's fifth-largest country by area ...

References

;Notes ;Bibliography * Williams S.T., Karube S. & Ozawa T. (2008) ''Molecular systematics of Vetigastropoda: Trochidae, Turbinidae and Trochoidea redefined.'' Zoologica Scripta 37: 483–506.

External links

*
Gmelin J.F. (1791). Vermes. In: Gmelin J.F. (Ed.) Caroli a Linnaei Systema Naturae per Regna Tria Naturae, Ed. 13. Tome 1(6). G.E. Beer, Lipsiae

Wood,_W._(1828)._Supplement_to_the_Index_Testaceologicus;_or_A_catalogue_of_Shells,_British_and_Foreign._Richard_Taylor,_London._Iv_ Wood,_W._(1828)._Supplement_to_the_Index_Testaceologicus;_or_A_catalogue_of_Shells,_British_and_Foreign._Richard_Taylor,_London._Iv_[+1
+_59_pp.,_plates_1-8">1">Wood,_W._(1828)._Supplement_to_the_Index_Testaceologicus;_or_A_catalogue_of_Shells,_British_and_Foreign._Richard_Taylor,_London._Iv_[+1
+_59_pp.,_plates_1-8
_Dornellas,_A._P.;_Graboski,_R._M.;_Hellberg,_M._E.;_Lotufo,_T._M._C._(2021)._Phylogeography_of_Agathistoma_(Turbinidae,_Tegulinae)_snails_in_tropical_and_southwestern_Atlantic._Zoologica_Scripta._DOI:_10.1111/zsc.12517
{{DEFAULTSORT:Agathistoma_Viridulum Agathistoma.html" ;"title="1
+_59_pp.,_plates_1-8.html" ;"title="1">Wood, W. (1828). Supplement to the Index Testaceologicus; or A catalogue of Shells, British and Foreign. Richard Taylor, London. Iv [+1
+ 59 pp., plates 1-8">1">Wood, W. (1828). Supplement to the Index Testaceologicus; or A catalogue of Shells, British and Foreign. Richard Taylor, London. Iv [+1
+ 59 pp., plates 1-8
Dornellas, A. P.; Graboski, R. M.; Hellberg, M. E.; Lotufo, T. M. C. (2021). Phylogeography of Agathistoma (Turbinidae, Tegulinae) snails in tropical and southwestern Atlantic. Zoologica Scripta. DOI: 10.1111/zsc.12517
{{DEFAULTSORT:Agathistoma Viridulum Agathistoma">viridulum Gastropods described in 1791