||Neritina virginea Linnaeus, 1758
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
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).
HABITAT AND DISTRIBUTION
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).
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
LIFE HISTORY AND POPULATION BIOLOGY
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
Little information is available concerning
the thermal tolerance for N. virginea, but the tropical
to subtropical range of the species suggests it prefers warmer
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
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.
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).
No known obligate associations exist for
N. virginea. However, virgin nerites are associated
with several organisms common to muddy and sandy intertidal
areas. For extensive lists of species found in these habitats
and others throughout the IRL, please refer to the links at
the left of this page.
No information is available at this time
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.
Report by: LH Sweat, Smithsonian Marine Station
at Fort Pierce
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Page last updated: 20 August 2009