Invasion History

First Non-native North American Tidal Record: 2017
First Non-native West Coast Tidal Record:
First Non-native East/Gulf Coast Tidal Record: 2017

General Invasion History:

Fissurella nimbosa is found on rocky intertidal shores from Veracruz State, Mexico and Puerto Rico to northern Brazil (Abbott 1974; Museum of Comparative Zoology 2017; Rosenberg 2017). In the winter of 2016-2017, two shells of this limpet were found in Coral Cove Park, Palm Beach County, Florida (Jacksonville Shell Club 2017).

North American Invasion History:

Invasion History on the East Coast:

In the winter of 2016-2017, a shell collector (Don Swenson) found two shells of Fissurella nimbosa in Coral Cove Park, Palm Beach County, Florida, near Jupiter Inlet (Jacksonville Shell Club 2017). This is the first record for this limpet in Florida and represents a range extension of ~2000 km. Since only two shells were found, establishment of this mollusk is unknown. The larval period is probably brief (Ward 1966), so hull fouling seems a more likely mode of transport than ballast water.


Fissurella nimbosa has an oblong-oval, flattened conical shell, with an oblong-oval 'keyhole' opening at the summit. The shell has numerous, radiating low ribs, separated by irregular grooves and crossed by fine concentric growth lines. The shell is 25-50 mm in length, and is buff-colored with many radiating stripes formed by reddish or purplish-brown rays (Abbott 1974).


Taxonomic Tree

Kingdom:   Animalia
Phylum:   Mollusca
Class:   Gastropoda
Subclass:   Prosobranchia
Order:   Archaeogastropoda
Family:   Fisurellidae
Genus:   Fisurella
Species:   nimbosa


Patella nimbosa (Linnaeus, 1758)
Fissurella balanoides (Reeve, 1850)
Patella mitella (Roding 1978, None)

Potentially Misidentified Species

Diodora viridula
Green Keyhole Limpet, ranging from Florida to the southern Caribbean. The rays are green and the keyhole is stained black (Abbott 1974).



Details of Fissurella nimbosa’s reproduction are unknown. In the similar species, F. barbadensis, sexes are separate. Eggs hatch out as free-swimming trochophores, metamorphosing into veliger larvae which are pelagic for about 2-3 days (Ward 1966). Adults of F. nimbosa graze on algae growing on intertidal rocks. Typically, the limpet spend the night in a rock scar in which the shell fits tightly, serving as a shelter, home base, and the center of the grazing area. About 60% of the grazing of F. nimbosa occurs at night, and often when the shells were awash in rising and falling tides (Franz 1990).



Trophic Status:




General HabitatRockyNone
Salinity RangePolyhaline18-30 PSU
Salinity RangeEuhaline30-40 PSU
Tidal RangeLow IntertidalNone
Vertical HabitatEpibenthicNone

Tolerances and Life History Parameters

General Impacts

No impacts have been reported for Fissurella nimbosa in Florida.

Regional Distribution Map

Bioregion Region Name Year Invasion Status Population Status
CAR-III None 0 Native Estab
CAR-IV None 0 Native Estab
CAR-VI None 0 Native Estab
SA-III None 0 Native Estab
CAR-I Northern Yucatan, Gulf of Mexico, Florida Straits, to Middle Eastern Florida 2017 Def Unk
S190 Indian River 2017 Def Unk

Occurrence Map

OCC_ID Author Year Date Locality Status Latitude Longitude


Abbott, R. Tucker (1974) Amarican Seashells, Van Nostrand Reinhold, New York. Pp. <missing location>

Academy of Natural Sciences of Philadelphia 2002-2016a Malacology Collection Search.

Fortic, Ana ; Mavric; Borut; Pitacco; Valentina; Lipej, Lovrenc (2021) Temporal changes of a fouling community: Colonization patterns of the benthic epifauna in the shallow northern Adriatic Sea, Regional Studies in Marine Science 45(101818): Published online

Harvard Museum of Comparative Zoology 2008-2021 Museum of Comparative Zoology Collections database- Malacology Collection.

Jarvis, Stephen; Clark, Paul F. (2021) Reappearance of Rhithropanopeus harrisii (Gould, 1841) (Crustacea, Decapoda, Brachyura) in U.K. waters: a new record from the River Thames, London, BioInvasions Records 10(3): 644\-653

Ramos-Espla, Alfonso A.; Izquierdo, Andres; Cinar, Melih Ertan (2013) Microcosmus exasperatus (Ascidiacea: Pyuridae), current distribution in the Mediterranean Sea, Marine Biodiversity Records 6: e89

Rosenberg, Gary 1995-2015 Malacolog.

U.S. National Museum of Natural History 2002-2021 Invertebrate Zoology Collections Database. <missing description>