The Nonindigenous Occurrences section of the NAS species profiles has a new structure. The section is now dynamically updated from the NAS database to ensure that it contains the most current and accurate information. Occurrences are summarized in Table 1, alphabetically by state, with years of earliest and most recent observations, and the tally and names of drainages where the species was observed. The table contains hyperlinks to collections tables of specimens based on the states, years, and drainages selected. References to specimens that were not obtained through sighting reports and personal communications are found through the hyperlink in the Table 1 caption or through the individual specimens linked in the collections tables.

Tarebia granifera
Tarebia granifera
(quilted melania)

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Tarebia granifera (Lamarck, 1822)

Common name: quilted melania

Synonyms and Other Names: Thiara granifera

Taxonomy: available through www.itis.govITIS logo

Identification: Generally brown in color, 7 to 11 whorls, elongately conic shell shape with several rows of small tubercles (Abbott 1952).

Size: 6 to 40 mm; average 25 mm shell length (Abbott 1952)

Native Range: Native to India west to Japan, south through southeast Asia (Madhyastha and Dutta 2012).

Hydrologic Unit Codes (HUCs) Explained
Interactive maps: Point Distribution Maps

Nonindigenous Occurrences: Florida, Hawaii, Idaho, Texas, Puerto Rico and US Virgin Islands.

Table 1. States with nonindigenous occurrences, the earliest and latest observations in each state, and the tally and names of HUCs with observations†. Names and dates are hyperlinked to their relevant specimen records. The list of references for all nonindigenous occurrences of Tarebia granifera are found here.

StateFirst ObservedLast ObservedTotal HUCs with observations†HUCs with observations†
CO198920152Arkansas Headwaters; San Luis
FL1948202011Alafia; Big Cypress Swamp; Caloosahatchee; Crystal-Pithlachascotee; Everglades; Florida Southeast Coast; Lake Okeechobee; Lower Suwannee; Santa Fe; South Atlantic-Gulf Region; Upper St. Johns
HI190020224Hawaii; Kauai; Maui; Oahu
ID199119911Upper Snake-Rock
PR196220094Cibuco-Guajataca; Culebrinas-Guanajibo; Eastern Puerto Rico; Southern Puerto Rico
TX196320205Lower Devils; Middle Guadalupe; San Marcos; Toyah; Upper San Antonio
VI198719931St. John-St. Thomas

Table last updated 7/25/2024

† Populations may not be currently present.

Ecology: This species is found from a range of environments; large rivers to small springs, in mountains and valleys, and silty or sand bottoms, riffles as well as pools (Abbott 1952; Prentice 1983). It is also found to do well in springs, where the temperature remans warm enough for the snail year-round (Abbott 1952).This species is capable of active upstream migration and is shown to disperse up to 100 m/month upstream (Appleton et al, 2009; Prentice 1983). Densities have been found to be sparse with large animals, or up to 400 specimens per square foot with smaller sized animals and obvious over-crowding (Abbott 1952). It is noted by Appleton et al. (2009) that the species often keeps most of body and shell buried in substrate in both field and in aquarium; this could lead to an underestimation of population proliferation, or an overlook of established populations altogether.

Sexual maturity is reached around 8-12mm in shell height, or typically 6-12 months (Abbott (1952). This species is parthenogenic (capable of self-feritlizaiton), and it is likely that most individuals of introduced populations are female clones, as many researchers have failed to find fertile males; the species is also ovoviviparous, meaning their eggs hatch within the body and live young are birthed (Abbott 1952; Appleton et al. 2009). It has been documented that females can birth one offspring every twelve hours (Abbott (1952).

Means of Introduction: This species is spread through the aquarium trade (Abbott 1952). The first specimens known in the United States were found in San Francisco in 1935, when an aquarium dealer had discovered them and sent the specimens to the National Museum (Murray, 1971). It is possible that the species is moved between close waterbodies via waterfowl, as reported by Appleton et al. (2009).

Impact of Introduction:
Summary of species impacts derived from literature review. Click on an icon to find out more...

EcologicalEconomicHuman Health



This species is known to outcompete, extirpate and replace native snail species, making the species an effective biological molluscicide used to remove native snails that carry parasites (Prentice 1983).


This species is a host to the parasite Centrocestus formosanus, which parasitizes fish gills (Appleton et al. 2009).

In the Caribbean, T. granifera is used as a biological molluscicide to replace native Biomphalaria snails that are vectors for schistosomasis in humans (Appleton et al 2009; van Oosterhout et al. 2013).


The introduction of this species in the Caribbean has affected the native hermit crab shell-use and behavior (van Oosterhout et al. 2013).


In Texas, T. granifera feeds on the eggs of the endangered fountain darter Etheostoma fonticola (Phillips et al. 2010).


Species has blocked pipes in large industrial plants and ponds in a fish hatchery in introduced areas in Africa, due to its tendency to become very dense (Appleton et al., 2009).

Human Health

Tarebia granfiera was thought to be an intermediate host for the Asian lungfluke Paragonimus westermani,  but this is not actually the case; however, this species still hosts other trematode parasites of the family Heterophyidae (Appleton et al., 2009).

References: (click for full references)

Abbott, R.T. 1952. A study of an intermediate snail host (Thiara granifera) of the oriental lung fluke (Paragonimus). Proceedings of the United States National Museum 102(3292):71-116.

Appleton, C.C., A.T. Forbes, and N.T. Demetriades. 2009. The occurrence, bionomics and potential impacts of the invasive freshwater snail Tarebia granifera (Lamarck, 1822) (Gastropoda: Thiaridae) in South Africa. Zoologische Mededelingen 83:525-536.

Madhyastha, A. and J. Dutta. 2012. Tarebia granifera. The IUCN Red List of Threatened Species 2012: e.T165813A1102513. Downloaded on 11 September 2015

Murray, H.D. 1971. The introduction and spread of Thiarids in the United States. The Biologist 53(3):133-135.

Phillips, C.T., M.L. Alexander, and R. Howard. 2010. Consumption of eggs of the endangered fountain darter (Etheostoma fonticola) by native and nonnative snails. Southwestern Naturalist 55(1):115-117. http://www.bioone.org/doi/abs/10.1894/JS-26.1.

Prentice, M.A. 1983. Displacement of Biomphalaria glabrata by the snail Thiara granifera in the field in habitats in St. Lucia, West Indies. Annals of Tropical Medicine and Parasitology 77(1):51-59.

van Oosterhout, C., R.S. Mohammed, R. Xavier, J.F. Stephenson, G.A. Archard, F.A. Hockley, S.E. Perkins, and J. Cable. 2013. Invasive freshwater snails provide resource for native marine hermit crabs. Aquatic Invasions 8(2):185-191.

Author: Morningstar, C.R. and A. J. Benson

Revision Date: 5/26/2020

Citation Information:
Morningstar, C.R. and A. J. Benson, 2024, Tarebia granifera (Lamarck, 1822): U.S. Geological Survey, Nonindigenous Aquatic Species Database, Gainesville, FL, https://nas.er.usgs.gov/queries/FactSheet.aspx?SpeciesID=1039, Revision Date: 5/26/2020, Access Date: 7/25/2024

This information is preliminary or provisional and is subject to revision. It is being provided to meet the need for timely best science. The information has not received final approval by the U.S. Geological Survey (USGS) and is provided on the condition that neither the USGS nor the U.S. Government shall be held liable for any damages resulting from the authorized or unauthorized use of the information.


The data represented on this site vary in accuracy, scale, completeness, extent of coverage and origin. It is the user's responsibility to use these data consistent with their intended purpose and within stated limitations. We highly recommend reviewing metadata files prior to interpreting these data.

Citation information: U.S. Geological Survey. [2024]. Nonindigenous Aquatic Species Database. Gainesville, Florida. Accessed [7/25/2024].

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