Phorcus atratus is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.[1][2]
| Phorcus atratus | |
|---|---|
| |
| A shell of Phorcus atratus | |
Scientific classification 
| |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Mollusca |
| Class: | Gastropoda |
| Subclass: | Vetigastropoda |
| Order: | Trochida |
| Superfamily: | Trochoidea |
| Family: | Trochidae |
| Subfamily: | Cantharidinae |
| Genus: | Phorcus |
| Species: | P. atratus
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| Binomial name | |
| Phorcus atratus (Wood, 1828)
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| Synonyms[1] | |
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Description
editThe height of the shell varies between 17 mm and 24 mm, its diameter between 16 mm and 19 mm. The solid, imperforate shell has a conical shape. The spire is conical. The apical whorls are eroded, the following dull cinereous or purplish-black, marked with several spiral rows of white spots, or with longitudinal zigzag white stripes. The base of the shell is generally tessellated or striped with white. The shell contains 5 to 6 whorls. The upper ones are marked with spiral impressed lines in young specimens, and two carinae, the latter giving the body whorl a squarish form. The aperture is oblique. The lip is not much thickened within. The short columella is obsoletely subdentate at its base. Above at the insertion it shows a heavy white callous spread upon the base, invading the umbilicus, and wholly closing it, or leaving only a narrow pit.
This species is quite variable in coloration, the white appearing either in oblique zigzags or in spots. The young are perforate.[3]
Distribution
editThis marine species occurs in the following locations:[1]
- Cape Verdes
- Canary Islands
- European waters (ERMS scope)
- Senegal
References
edit- ^ a b c Phorcus atratus (Wood, 1828). Retrieved through: World Register of Marine Species on 18 December 2018.
- ^ Donald K.M., Preston J., Williams S.T., Reid D.R., Winter D., Alvarez R., Buge B., Hawkins S.J., Templado J. & Spencer H.G. 2012. Phylogenetic relationships elucidate colonization patterns in the intertidal grazers Osilinus Philippi, 1847 and Phorcus Risso, 1826 (Gastropoda: Trochidae) in the northeastern Atlantic Ocean and Mediterranean Sea. Molecular Phylogenetics and Evolution, 62(1): 35–45
- ^ Tryon (1889), Manual of Conchology XI, Academy of Natural Sciences, Philadelphia (described as Monodonta tamsi)
- Wood W., 1828: Supplement to the Index Testaceologicus or a catalogue of shells, British and foreign ; London, privately published; pp. VI + 59 + 8 pl
- Nordsieck F., 1974: Il genere Osilinus Philippi, 1847 nei mari europei ; La Conchiglia 9-10 (67-68): 21-23
- Talavera F.G., 1978: Moluscos marinos de las Islas Salvajes. In: Contribución al estudio de la historia natural de las Islas Salvajes; * Aula de Cultura de Tenerife p. 119-128, 1 pl.
External links
edit
- "Osilinus atratus atratus". Gastropods.com. Retrieved 16 January 2019.