''Marginella gemmula'' 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 ...

of very small

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 ...

Marginellidae, the margin snails.

Description

Shell

The shell of Marginella gemmula, while glossy and smooth to the touch, has spires that can be anywhere from flat to moderately elevated. Most shells have various colors, but a small number can be colorless. On the outside of the shell, the columella has four plaits. The outside lip is thicker than other such creatures, and the inside of the shell sports
denticulate
set of teeth and/or folds. Unlike other gastropods, Marginella gemmula's

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 ...

is not very deep, but is still present. There is no operculum present with Marginella gemmula.

Flesh

The head of Marginella gemmula i
bifurcated
with the siphon extending behind it. When moving, the foot of the animal extends past the shell.

Distribution

This species occurs in

Angola , national_anthem = " Angola Avante"() , image_map = , map_caption = , capital = Luanda , religion = , religion_year = 2020 , religion_ref = , coordina ...

at depths between 15 m and 35 m.

References

* Gofas, S.; Afonso, J.P.; Brandào, M. (Ed.). (S.a.). Conchas e Moluscos de Angola = Coquillages et Mollusques d'Angola. hells and molluscs of Angola Universidade Agostinho / Elf Aquitaine Angola: Angola. 140 pp. * Cossignani T. (2006). Marginellidae & Cystiscidae of the World. L'Informatore Piceno. 408pp * Gofas S. & Fernandes F. 1994. The Marginellidae of Angola. The genus Marginella. Journal of Conchology 35(2): 103-119

External links

*
Dautzenberg P. (1912) Mission Gruvel sur la côte occidentale d'Afrique (1909-1910): Mollusques marins. Annales de l'Institut Océanographique, Paris, (Nouvelle Série) 5(3): 1-111, pl. 1-3
{{Commons category Endemic fauna of Angola

gemmula ''Gemmula'', common name the gem turrids, is a genus of sea snails, marine gastropod mollusks in the family Turridae, the turrids. These snails have been recorded as fossils from the Paleocene to the Quaternary (from 66.043 to 0.012 Ma). Fossils ...

Gastropods described in 1913