Neritina virginea (Linnaeus, 1758)
Family: Neritidae
Common names: Virgin Nerite
Neritina virginea image
Neritina virginea  

Species Description: The virgin nerite, Neritina virginea, is a common intertidal gastropod in Florida belonging to the family Neritidae. Members of this family are characterized by a small, globular shell, and a calcareous operculum bearing one small, pointed hook at the end (Abbott & Morris 1995). The extremely polished shell of the virgin nerite has a semiglobular shape, with 3-4 whorls. Shell color is variable, and may be red, black, grayish green, tan or yellow, usually marked with lines and dots of black or purple (Abbott & Morris 1995, Andrews 1935). The operculum is smooth and generally black, closing on an oval aperture with a thin outer tip (Martins et al. 2002).

Potentially Misidentified Species: Several other species of small gastropods occur in the intertidal areas of the IRL where N. virginea is abundant. Of these, the two species that are most closely related to the virgin nerite are the olive nerite, Neritina reclivata and the Clench's nerite, N. clenchi.

The shell of the olive nerite measures about 1.3 cm, is semiglobular with 3-4 whorls, smooth, solid green or greenish with tiny black lines (Abbott & Morris 1995). The operculum is dark brown to black. This species is reported to prefer brackish waters and tidal areas of streams (Abbott & Morris 1995).

At a maximum of about 2 cm, the shell of the Clench's nerite is slightly larger than N. reclivata or N. virginea (Andrews 1994). The shell shape is less globular than many other Neritina species, with 3-4 four whorls and a moderately pointed apex (Abbott & Morris 1995). Shell color is variable, with an area on the interior of the shell stained orange-yellow. The operculum is black to pink in color. This species can be found in fresh to brackish waters (Abbott & Morris 1995).

Regional Occurrence & Habitat Preference: The virgin nerite has been reported from Florida to Brazil, the Gulf of Mexico and Bermuda (Abbott & Morris 1995, Andrews 1994, Blanco et al. 2005, Boehs et al. 2004, Martins et al. 2002). Populations are found in intertidal areas, including mud bottoms and the roots of associated vegetation (Abbott & Morris 1995, Martins et al. 2002).

IRL Distribution: The virgin nerite can be found throughout the IRL, usually in association with muddy or sandy areas near submerged or intertidal vegetation such as grass flats.

Age, Size, Lifespan: The maximum age of the virgin nerite is unknown, and lifespan varies with food availability and environmental conditions. The maximum shell length of N. virginea is about 1.3 cm (Abbott & Morris 1995).

Reproduction & Embryology: Reproductive behaviors and embryology of N. virginea are poorly documented. After fertilization, the yellow, clustered eggs are laid in gelatinous capsules on nearby mollusk shells (Andrews 1994). Like many other mollusks, the virgin nerite reproduces via a planktonic larva called a veliger. These larvae remain in the water column until they reach the final stage, or pediveliger, at which time they search for a suitable location to settle and metamorphose into juvenile snails.

Temperature: Little information is available concerning the thermal tolerance for N. virginea, but the tropical to subtropical range of the species suggests it prefers warmer waters.

Salinity: The virgin nerite inhabits brackish waters, but often travels far up rivers and streams (Abbott & Morris 1995, Blanco & Scatena 2005). Salinity may play a role in the shell color of N. virginea. Andrews (1935) found that individuals in freshwater displayed duller, darker shells than their brightly-colored counterparts inhabiting more saline areas.

Trophic Mode: Little information is available concerning the dietary preferences of N. virginea. However, most neritids feed on organisms comprising the biofilm (slime layer) on intertidal surfaces, including: algae, detritus, flagellates, diatoms and nematodes.

Predators: Virgin nerites are likely preyed upon by a variety of birds, fishes and invertebrates. This species has the ability to mend its shell after failed attempts by crushing predators (Andrews 1935).

Associated Species: No known obligate associations exist for N. virginea. However, virgin nerites are associated with several organisms common to muddy and sandy intertidal areas. 

Abbott, RT & PA Morris. 1995. A field guide to shells: Atlantic and Gulf coasts and the West Indies, 4th edition. Houghton Mifflin Co. Boston, MA. USA.

Andrews, EA. 1935. Shell repair by the snail, Neritina. J. Exp. Zool. 70: 75-107.

Andrews, J. 1994. A field guide to shells of the Florida coast. Gulf Publishing Co. Houston, Texas. USA. 182 pp.

Blanco, JF & FN Scatena. 2005. Floods, habitat hydraulics and upstream migration of Neritina virginea (Gastropoda: Neritidae) in northeastern Puerto Rico. Carib. J. Sci. 41: 55-74.

Boehs, G, Absher, TM & A da Cruz-Kaled. 2004. Composition and distribution of benthic mollusks on intertidal flats of Paranaguá Bay (Paraná, Brazil).

Kaplan, EH. 1988. A field guide to southeastern and Caribbean seashores: Cape Hatteras to the Gulf coast, Florida, and the Caribbean. Houghton Mifflin Co. Boston, MA. USA. 425 pp.

Martins, IX, Matthews-Cascon, H & C de Almeida Rocha-Barreira. 2002. On the morphology of Neritina virginea (Linnaeus, 1758) (Gastropoda, Neritidae). Thalassas. 18: 9-16.

Neritina virginea image
Neritina virginea  
Neritina virginea image
Neritina virginea