Marisa cornuarietis (giant ramshorn)
- Summary of Invasiveness
- Taxonomic Tree
- Notes on Taxonomy and Nomenclature
- Distribution Table
- History of Introduction and Spread
- Risk of Introduction
- Habitat List
- Hosts/Species Affected
- List of Symptoms/Signs
- Biology and Ecology
- Natural enemies
- Notes on Natural Enemies
- Means of Movement and Dispersal
- Pathway Causes
- Pathway Vectors
- Plant Trade
- Impact Summary
- Economic Impact
- Environmental Impact
- Threatened Species
- Risk and Impact Factors
- Uses List
- Detection and Inspection
- Similarities to Other Species/Conditions
- Prevention and Control
- Principal Source
- Distribution Maps
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IdentityTop of page
Preferred Scientific Name
- Marisa cornuarietis Linnaeus, 1758
Preferred Common Name
- giant ramshorn
Other Scientific Names
- Ampullaria chiquitensis d'Orbigny, 1838
- Ampullaria knorrii Philippi, 1852
- Ampullaria rotula Mousson, 1869
- Ceratodes fasciatus Guilding, 1828
- Ceratodes rotula Mousson, 1869
- Helix cornu arietis Linnaeus, 1758
- Marisa chiquitensis d'Orbigny, 1838
- Marisa cornuarietis knorrii Philippi, 1852
- Marisa intermedia Gray, 1824
- Planorbis contrarius O.F. Müller, 1774
International Common Names
- English: Columbian ramshorn snail; golden horn marissa; striped ram's horn snail; stripehorn
- Spanish: caracol cuerno de carnero; caracol rosquilla
- French: escargot géant béliers corne; l'escargot géant de la traverse; marise; marise aplatie
Local Common Names
- Antigua and Barbuda: caracol cuerno de carnero
- Germany: Paradise-Schnecke
- Puerto Rico: hard disk snail
Summary of InvasivenessTop of page
M. cornuarietis is an ampullarid freshwater snail presumed native to northern South America and Central America. This species has established outside of its native range in several Caribbean nations, southern USA, Africa and Spain. It was intentionally introduced into new areas as a biocontrol agent for unwanted macrophyte growth and control of pulmonate snail hosts of trematode parasites afflicting humans and livestock. However, use of M. cornuarietis for such purposes is no longer promoted in recognition of the species’ adverse environmental impacts. Nevertheless, M. cornuarietis is still traded widely as an aquarium pet. M. cornuarietis is primarily a herbivore, feeding on macrophytes. This diet, coupled with their large body mass, high reproductive output and often high densities mean these snails can effect rapid changes in macrophyte community structure, with consequent perturbations of nutrient balance, turbidity and trophic structure of water bodies. M. cornuarietis also has omnivorous tendencies and has been shown to predate on snail eggs and neonates and other soft-bodied invertebrates. Among endemic threatened species in the invaded upper San Marcos and Comal rivers in central Texas, the fountain darter, Etheostoma fonticola, is considered at risk from M. cornuarietis predation on eggs and from herbivory of macrophytes in the critical habitat.
Taxonomic TreeTop of page
- Domain: Eukaryota
- Kingdom: Metazoa
- Phylum: Mollusca
- Class: Gastropoda
- Subclass: Caenogastropoda
- Order: Architaenioglossa
- Unknown: Ampullarioidea
- Family: Ampullariidae
- Genus: Marisa
- Species: Marisa cornuarietis
Notes on Taxonomy and NomenclatureTop of page
M. cornuarietis belongs to the family Ampullariidae, commonly known as the apple snails. The genus Marisa contains only one other species, M. planogyra Pilsbry, 1933 present in the Pantanal region of Brazil (Cowie and Thiengo, 2003).
DescriptionTop of page
Shell: dextrally coiled. Juveniles globose. During post-hatching ontogeny shell growth is of planispiral coiling, producing 3.5 to 4 flat whorls in which the juvenile spire is not elevated above the adult whorls and the umbilicus is very widely open. Shell in adults 18-22 mm in height, 48-56 mm in diameter, more-or-less glossy but with growth lines (transverse striate) that are most prominent near the aperture. Aperture plane makes a slight angle with the shell axis (10°); peristome (aperture margin) generally continuous, but interrupted by prominent callus on parietal wall in immature snails; peristome simple, sharp, but late in ontogeny becoming reflected and thickened. Yellow to brownish ground colour with 3-6 dark red-brown to black spiral bands over periphery and umbilicus; banding pattern can be absent. Adult mass about 500-650 mg. With a weak sexual dimorphism, shell of males tending smaller, thicker and with more rounded aperture. The planispiral shell is orientated vertically.
Operculum: yellowish to brownish corneous, concentric.
Adults: head region with prominent snout, dorsally bearing two long slender cephalic tentacles, each with a black-pigmented eye borne on short peduncles at their base and at its anterior fringe bearing two slender inferior (labial) tentacles and a small mouth ventrally. Tail region moderately long, dorsally carrying an operculum. Snout, tentacles and dorsal aspects of foot and tail mottled grey to black. Foot sole broadly-rounded anteriorly, bluntly-pointed posteriorly; uniformly pale.
Mantle cavity possessing a single unipectinate gill (ctenidium) as the principal site of respiratory oxygen uptake, but additionally the cavity itself modified as a lung for aerial respiration. A manoeuvrable, inwardly rolled extension of the mantle edge functioning as an inhalant siphon, drawing oxygenated water into mantle cavity and over the gill. Dioecious, with internal fertilization. Male reproductive tract consisting of a single testis in upper whorls connected via vas deferens to seminal vesicle and prostate gland and thence to male genital papilla opening through floor of the mantle cavity. Sperm groove traversing mantle cavity to reach the male genitalia on left comprising penial sac proximal to penis housed within the penial sheath, a muscle modification of the mantle edge. Penis muscular, penetrated by a coiled, slender tubular spermiduct, bearing externally glands that extrude mucous secretion through an anterior duct during copulation; penis distendible during copulation, extending beyond mantle cavity and from which terminal part of the spermiduct protrudes as an intromittent organ.
Female reproductive tract consisting of a single ovary in upper whorls connected via the renal gonoduct – elaborated as a the receptaculum seminis, the site for sperm storage and fertilization – to the saccular bursa copulatrix and the glandular chambers of the pallial gonoduct comprising albumen and capsule glands and thence opening to the female genitital papilla in the anterior left aspect of mantle cavity. Bursa copulatrix functions as site for receival of sperms of the male and from which any defect sperm cells that aren't able to migrate to the receptaculum seminis, are absorbed. Female glands function to provide nutriment and capsulation of the eggs and egg-mass, greatly increasing in volume during breeding season.
Radula: taenioglossate (formula 2.1.c.1.2), i.e. seven teeth in each transverse row are arranged such that the central tooth is flanked on each side by a lateral tooth and two marginal teeth.
DistributionTop of page
The native range of M. cornuarietis extends from Central America (Panama, Costa Rica) to southern Brazil. Nonetheless, within this range there has been some variance among authors as to what constitutes native and introduced. Nguma et al. (1982) considered M. cornuarietis as autochthonous to habitats in the Magdalena and Orinoco river systems in Colombia and Venezuela. Generally, Venezuela, Colombia, Trinidad and Tobago and the Amazon Basin regions of Brazil, Bolivia and Peru are considered to be the native range, but the species’ status in French Guyana, Guyana and Surinam and in countries of the southern Caribbean, is ambiguous. The lack of invasiveness in these latter countries may indicate its native status there.
Additionally, M. cornuarietis has been reported from southern regions of South America. Cowie and Thiengo (2003) argued that specimens from south of the Amazon Basin were wrongly identified as M. cornuarietis by Ihering (1919) and these records had been perpetuated in the subsequent literature. Therefore Cowie and Thiengo (2003) considered Paraguay, Uruguay and Argentina as being not part of this species' native distribution. Nonetheless, Quintana (1982) document specimen records from the Alto Paraguay region (as M. chiquitensis) and Simone (2006) records the species from Paraguay, Argentina and Uruguay.
M. cornuarietis has been introduced into Egypt, Puerto Rico, South Africa, Sudan, Tanzania and the USA (California, Florida, Idaho and Texas). This species was also introduced into New Zealand and evaluated as a potential biocontrol agent for aquatic weeds, however, it was not released (Chapman et al., 1974; NIWA, 2002; Horgan et al., 2014).
Distribution TableTop of page
The distribution in this summary table is based on all the information available. When several references are cited, they may give conflicting information on the status. Further details may be available for individual references in the Distribution Table Details section which can be selected by going to Generate Report.Last updated: 10 Jan 2020
|Continent/Country/Region||Distribution||Last Reported||Origin||First Reported||Invasive||Reference||Notes|
|Egypt||Present||Introduced||Demian and Kamel (1973); Brown (1994); Damme et al. (2010); Cowie and Hayes (2012); Horgan et al. (2014)||Introduced for biological control of the intermediate hosts of schistosomes|
|South Africa||Present, Only in captivity/cultivation||Introduced||1986||Aardt and Kock (1991)||Introduced for schistosomiasis research purposes. No evidence of establishment in the field (Appleton and Miranda, 2015)|
|Sudan||Present, Localized||Introduced||1981||Haridi and Jobin (1985); Madsen et al. (1988); Madsen (1990); Brown (1994); Cowie and Hayes (2012); Horgan et al. (2014); CABI (Undated);||Introduced as biological control agent for Biomphalaria hosts of Schistosomes|
|Tanzania||Present, Localized||Introduced||1977||Msangi and Kihauli (1972); Nguma et al. (1982); Brown (1994); Cowie and Hayes (2012); Horgan et al. (2014)||Introduced as biological control agent for Biomphalaria hosts of Schistosomes|
|Israel||Present, Only in captivity/cultivation||Introduced||Roll et al. (2009); Milstein et al. (2012)||Has evidently become extinct in the field - now confined to aquaria|
|Spain||Present, Localized||Introduced||2012||Arias and Torralba-Burrial (2014)||Detected near Colloto, in Nora River, Oviedo, Asturias, Spain|
|Costa Rica||Present||Native||Taylor (1993); Simone (2006); Cowie and Hayes (2012); Horgan et al. (2014)|
|Cuba||Present, Widespread||Introduced||Invasive||Aguayo and Jaume (1954); Hunt (1958); Ferrer Lopez et al. (1991); Gutiérrez et al. (1997); Pointier et al. (2005); Fernndez et al. (2006); Simone (2006); Vázquez Perera and Perera Valderrama (2010); Cowie and Hayes (2012); Horgan et al. (2014)||First reported: 1940s|
|Dominican Republic||Present, Widespread||Introduced||Invasive||Vargas et al. (1991); Perera and Walls (1996); Cowie and Hayes (2012); Horgan et al. (2014)|
|Grenada||Present, Localized||Introduced||2009||Invasive||Charles (2009)||Detected at three locations in northern Grenada (Sulphur Springs, Salle River; river near Bathway Beach; Palmiste Lake)|
|Guadeloupe||Present, Widespread||Introduced||1987||Pointier et al. (1991); Pointier and Augustin (1999); Pointier and David (2004); Cowie and Hayes (2012); Horgan et al. (2014)||Introduced as biological control agent for planorbid vectors of Schistosoma|
|Martinique||Present, Widespread||Introduced||1987||Invasive||Pointier (1999); Pointier (2001); Kairo et al. (2003); Cowie and Hayes (2012); Horgan et al. (2014)||First detected at Anse Rivière and Quartier Boisneuf|
|Panama||Present||Native||Simone (2006); Cowie and Hayes (2012); Horgan et al. (2014)|
|Puerto Rico||Present, Widespread||Introduced||1952||Invasive||Oliver-Gonzales et al. (1956); Jobin et al. (1977); Cowie and Hayes (2012); Horgan et al. (2014); CABI (Undated)||Evidently established as a passively introduced adventive, but spread aids by use as a biological control agent of the intermediate host snails of Schistosoma|
|Saint Kitts and Nevis||Present, Localized||Introduced||Ferguson et al. (1960); Prentice (1983); Bass (2006); Cowie and Hayes (2012); Horgan et al. (2014)||Introduced to St Kitts as biological control agent of the intermediate host snails of Schistosoma; First reported: 1950s|
|Trinidad and Tobago||Present, Widespread||Native||Bass (2003); Cowie and Thiengo (2003); Simone (2006); Dipnarine (2015)|
|United States||Present||CABI (Undated a)||Present based on regional distribution.|
|-California||Present||Introduced||Howells et al. (2006); Rawlings et al. (2007)|
|-Florida||Present, Widespread||Introduced||1957||Invasive||Hunt (1958); Edmondson (1959); Hale (1964); Seaman and Porterfield (1964); Robins (1971); Dundee (1974); Thompson (1984); Howells et al. (2006); Rawlings et al. (2007); Cowie and Hayes (2012); Horgan et al. (2014); USGS NAS (2016)||First detected in Coral Gables in 1957. Has spread to many other counties in southern Florida|
|-Idaho||Present, Localized||Introduced||1992||Bowler and Frest (1992); Frest and Bowler (1992); Frest and Johannes (2000); Howells et al. (2006); Rawlings et al. (2007)||Reported from a tropical fish hatchery on Deep Creek in the central Snake River drainage, Twin Falls County in 1992|
|-Texas||Present||Introduced||1981||Neck (1984); Horne et al. (1992); Howells (2001); Howells et al. (2006); Rawlings et al. (2007); Karatayev et al. (2009); Cowie and Hayes (2012); Horgan et al. (2014)||First reported in headwaters of San Marcos River, San Marcos (city), Hays County in 1981. Has spread to other river systems. Evidently in decline (Howells et al., 2006)|
|Argentina||Present||CABI (Undated b)||Cowie and Thiengo (2003) conclude that records for south of the Amazon basin by Ihering (1919) to be incorrect. This argument is accepted by Pastorino and Darrigan (2011). However, Simone (2006) records the species from Paraguay, Argentina and Uruquary|
|Bolivia||Present, Widespread||Native||Cowie and Thiengo (2003); Simone (2006)|
|Brazil||Present, Widespread||Native||Cowie and Thiengo (2003); Simone (2006)|
|-Mato Grosso do Sul||Present||Simone (2006)|
|-Rio Grande do Sul||Present||Ihering (1919); Simone (2006); Agudo-Padrón (2009)||Cowie and Thiengo (2003) conclude that records for south of the Amazon basin by Ihering (1919) to be incorrect. However, the species continues to be recorded from the State (Agudo-Padrón, 2009)|
|Colombia||Present, Widespread||Native||Horne et al. (1992); Cowie and Thiengo (2003); Cowie and Hayes (2012)|
|French Guiana||Present, Widespread||Introduced||Cowie and Thiengo (2003); Simone (2006); Cowie and Hayes (2012); Horgan et al. (2014)||Presence considered not yet confirmed according to Massemin et al. (2009)|
|Guyana||Present, Widespread||Introduced||Cowie and Thiengo (2003); Cowie and Hayes (2012); Horgan et al. (2014)|
|Paraguay||Present||Native||Ihering (1919); Quintana (1982); Simone (2006)||Cowie and Thiengo (2003) conclude that records for south of the Amazon basin by Ihering (1919) to be incorrect. This argument is accepted by Pastorino and Darrigan (2011). However, Quintana (1982) document specimen records from Alto Paraguay region (as Marisa chiquitensis), and Simone (2006) records the species from Paraguay, Argentina and Uruquary|
|Peru||Present, Localized||Native||Ramírez et al. (2003)||Amazonia|
|Suriname||Present||Introduced||Simone (2006); Cowie and Hayes (2012); Horgan et al. (2014)||Presence considered not yet confirmed according to Geijskes and Pain (1957), but nonetheless recorded by Simone (2006)|
|Uruguay||Present||Simone (2006)||Cowie and Thiengo (2003) conclude that records for south of the Amazon basin by Ihering (1919) to be incorrect. This argument is accepted by Pastorino and Darrigan (2011). However, Simone (2006) records the species from Paraguay, Argentina and Uruquary|
|Venezuela||Present, Widespread||Native||Cowie and Thiengo (2003); Cowie and Hayes (2012); Horgan et al. (2014); Pointier (2015)|
History of Introduction and SpreadTop of page
M. cornuarietis established as an adventive in Puerto Rico, but subsequently became widely distributed in the Caribbean and thence in Africa (Egypt, Sudan, Tanzania) as a result of biological control programs directed at pulmonate snail intermediate hosts of Schistosoma parasites and/or aquatic weeds. M. cornuarietis also occurs widely in aquaria and is traded as an aquarium pet throughout the world (Ng et al., 2014; Ng et al., 2016). Establishment in the field in the Florida, Texas, Idaho and California, USA, Spain and possibly elsewhere has been attributed to deliberate dumping of unwanted aquarium contents into natural or artificial waterways and waterbodies.
Risk of IntroductionTop of page
The primary risk of spread for this species into new locations is through the pet/domestic aquarium trade and the aquatic plants trade for pond gardening and landscaping (Howells et al., 2006; Rawlings et al., 2007). There is some potential for natural spread of this species locally (Robins, 1971). M. cornuarietis poses the greatest potential for establishment in tropical regions due to its thermal requirements. In subtropical and temperature regions the extent of suitable warm-water habitat is restricted to tectonically-heated springs, streams and lakes and artificially thermal waters arising from industrial and thermal-electric facilities.
HabitatTop of page
M.cornuarietis occurs in freshwater aquatic ecosystems with macrophytic vegetation, including lakes, rivers, ponds, swamps and irrigation and drainage canals. It prefers still or slow-flowing systems, typically at depths less than one metre (Ferguson and Palmer, 1958).
Habitat ListTop of page
|Terrestrial ‑ Natural / Semi-natural||Wetlands||Principal habitat|
|Irrigation channels||Principal habitat|
|Rivers / streams||Principal habitat|
Hosts/Species AffectedTop of page
The principal agricultural crop that may be adversely impacted by M. cornuarietis is Oryza sativa (paddy rice) (Ortiz-Torres, 1962). Seedling rice plants may be killed by feeding, especially when there is no other source of food but the occurrence of this is low (Ortiz-Torres, 1962; Seaman and Porterfield, 1964).
SymptomsTop of page
M. cornuarietis feeds on subsurface vegetation, typically severing stems and consuming these cuttings.
List of Symptoms/SignsTop of page
|Growing point / external feeding|
|Leaves / external feeding|
|Roots / external feeding|
|Stems / external feeding|
|Vegetative organs / external feeding|
|Whole plant / external feeding|
|Whole plant / plant dead; dieback|
|Whole plant / uprooted or toppled|
Biology and EcologyTop of page
M. cornuarietis has 14 haploid chromosomes (Lutfy and Demian, 1965). There evidently no dimorphic sex chromosomes. The presence of bands on the shell is under the control of a single locus gene, with the band-less condition being recessive (Dillon, 2003).
M. cornuarietis is a dioecious (separate sexes), outcrossing species. Breeding tends to occur in spawning groups with a clutch size of 50-210 (Cowie, 2002). Keller et al. (2007) indicated the fecundity of M. cornuarietis to be in the order of 1700 eggs per female a year. Females are able to store sperm in the genital tract for months after copulation, enabling spawning to be delayed if necessary to coincide with return of favourable environmental conditions.
Physiology and Phenology
The productivity of M. cornuarietis populations is dependent on the availability of food and water temperature. At high temperatures and high abundance of food the lifecycle is short, such that only three months is required to reach sexual maturity and as many as three generations per year may be produced. Productivity is nonetheless curtailed by unfavourable conditions, such as drought and food shortages. There is some ambiguity as to the reproductive phenology of the species. Some authors have found that reproduction occurs throughout the year, while others have found marked seasonality in the reproductive cycle, with a two-month spawning season starting at the end of the calendar year. This variation has raised the possibility of cryptic species within what has been commonly considered M. cornuarietis (OECD 2010) or that the reproductive cycle is conditional on the environmental setting.
Estimates of the longevity of M. cornuarietis indicate three years (Cowie, 2002). Nonetheless, the proportion surviving after 1 year was 0.03 in Sudan (Haridi et al., 1985) and 0.10 in Puerto Rico (Jobin, 1970). It is unclear from the current literature if individuals contribute to more than one generation in the field.
M. cornuarietis is a diurnally active species. It exhibits a degree of amphibiousness and is able to aestivate in muddy residues during periods of low water levels provided temperatures do not reach lethal levels. After hatching, young M. cornuarietis feed on the remains of the egg-mass for the first few days. Later they disperse locally to forage.
Population Size and Density
Within its introduced range, M. cornuarietis can achieve densities in the order of 50-175 per m2 (Haridi et al., 1985; Vargas et al., 1991). In North America, population densities were found to fluctuate greatly between years (Howells et al., 2006).
M. cornuarietis is omnivorous, though predominantly a generalist herbivore. The species feeds primarily on living and decaying aquatic macrophytes (Ferguson and Palmer, 1958; Robins, 1971), but will also graze algae. Some differences in food choices have been observed between adults and juveniles (Cedeno-Leon and Thomas, 1982). Food preferences under conditions of high water temperatures have been found to correlate with a preference for high protein diets (Hofkin et al., 1991). M. cornuarietis has been reported to predate on conspecific eggs (Demian and Lufty, 1965a), but Michelson and Augustine (1957) and Seaman and Porterfield (1964) indicated that adult Marisa do not destroy their own eggs or young. Predation on eggs and snails of other gastropod species has been well documented (Demian and Luffy, 1965a; Demian and Luffy 1965b; Demian and Luffy, 1966; Chi et al., 1971; Ferguson, 1977; Godan, 1979; Cedeno-Leon and Thomas, 1983; Hofkin et al., 1991; Pointier and Jourdane 2000).M. cornuarietis also predates on some other aquatic invertebrates (worms, microcrustaceans) and readily consumes carrion such as dead fish (Demian and Lutfy, 1966; Demian and Kamel, 1973; Cazzaniga and Estebenet, 1984; Hofkin et al., 1991; Stryker et al., 1991). Although M. cornuarietis will prey on other gastropods, laboratory observations of M. cornuarietis collected in Texas waters indicated that they consume other snails only when macrophytes are absent and the ampullariids are especially hungry (Howells et al., 2006). M. cornuarietis has a broad host range. In laboratory experiments, M. cornuarietis fed on Nasturtium oflicinale (watercress), a species of Cabomba and Elodea and Eichhornia crassipes (water hyacinth) (Ferguson and Palmer, 1958). In the field Xanthosoma atrovirens is commonly fed upon (Ferguson and Palmer, 1958) and in Puerto Rico, the density of native waterlily, Nymphaea ampla were substantially reduced (Peebles et al., 1972). The 1987 deliberate introduction of M. cornuarietis to Grand Etang lake in Guadeloupe was associated with rapid decline of Pistia stratiotes (water lettuce) (Pointier et al., 1991; Pointier, 1999). In the San Marcos and Comal Rivers of Texas, M. cornuarietis has been observed to graze on native Ludwigia repens (water primrose) and Vallisneria americana (tape grass) (Neck, 1984). M. cornuarietis may also feed on Oryza sativa (paddy rice) (Ortiz-Torres, 1962). Shortly after M.cornuarietis established in Coral Gables and Tamiami Trail canals near Miami, Florida, Seaman and Porterfield (1964) observed M. cornuarietis feeding on Cabomba caroliniana. In subsequent experiments M.cornuarietis was recorded feeding on Ceratophyllumdemersum (macrophytes coontail), Najas guadalupensis (southern naiad), Potamogeton illinoensis (Illinois pondweed), Salvinia minima (salvinia) and the invasive species Hydrilla verticillata and Alternanthera philoxeroides (alligatorweed).
Being ectothermic, the biology of M. cornuarietis is critically dependent on ambient temperature, with influence on activity levels and rates of respiration, growth, reproduction and survival. In the field, M. cornuarietis has been observed to occur over the range 13-30°C, but temperatures in the range ~22-28°C are considered optimal. Within this range, M. cornuarietis eggs took 17 days at 22°C and 8 days at 28°C to hatch (Aufderheide et al., 2006) and growth rate of juveniles correspondingly increased (Aufderheide et al., 2006; Selck et al., 2006). Aufderheide et al. (2006) found rearing snails at temperatures between 22-28°C did not influence the rates of egg production or egg clutch size. M. cornuarietis is unable to tolerate low temperatures (Robins, 1971; Thomas, 1975; Cowie and Hayes, 2012). Egg development was found to cease at 11°C, although adults may survive for over 24 hours. Mortality was 100% after 8 h at 8°C. An intolerance of low temperatures has been considered a likely major factor in restricting establishment of M. cornuarietis in North America to thermally stable headwater springs, heated power plant reservoirs, or southern latitudes (Howells et al., 2006). Exposure to 40°C is lethal to M. cornuarietis within 1-4 hours. While foraging activity is normal at 33.5-35.5°C, eggs do not develop successfully at 35-37°C (Robins, 1971; Cowie and Hayes, 2012). M. cornuarietis has gills as well as a lung, to ensure efficient underwater respiration even in condition of low levels of dissolved oxygen. Nonetheless, M. cornuarietis is anoxia intolerant, surviving only brief periods without adequate oxygen supply (von Brand et al., 1950). M. cornuarietis exhibits some amphibiousity and is able to respirate exposed to air for a period, although oxygen uptake is slower than those during submerged aquatic respiration (Freiberg and Hazelwood, 1977). While freshwater habitat is required for breeding, M. cornuarietis is known to tolerate relatively high salt concentrations (Hunt, 1961; Robins, 1971; Santos et al., 1987) and they are occasionally found in brackish-waters. M. cornuarietis productivity is dependent on adequate calcium concentrations in the water (Dillon, 2000). An increase of calcium concentration from 25 to 100 mg/l has been shown to increase both survivorship and shell size (Meier-Brook, 1978).
Natural enemiesTop of page
Notes on Natural EnemiesTop of page
There have been very few studies of the natural enemies of M. cornuarietis. The great-tailed grackle, Quiscalus mexicanus, is a snail-eating bird common throughout the Americas. It was found to be a predator of M. cornuarietis in Florida (Seaman and Porterfield, 1964). The snail kite, Rostrhamus sociabilis, is widely distributed in the tropical Americas and feeds almost exclusively on ampullariids including M. cornuarietis (Snyder and Kale, 1983; Howells et al., 2006).
Means of Movement and DispersalTop of page
Natural spread of M. cornuarietis in lotic systems has been reported by rafting downstream on floating macrophytes (Robins, 1971). In addition, M. cornuarietis can migrate upstream against a moderate current (Ferguson and Palmer, 1958).
M. cornuarietis is popular in aquariums and sold internationally in aquarium shops servicing the pet/domestic aquarium trade and scientific laboratories. M. cornuarietis has been intentionally introduced to several countries as a competitor and facultative predator of pest aquatic snails, especially those involved in transmission of schistosome trematodes. It was also introduced to several countries as a biological control agent for aquatic macrophyte weeds. However, the use of M. cornuarietis in biological control programmes is no longer considered an environmentally acceptable approach to management of parasite vectors and invasive aquatic weeds.
The high risk pathway for introduction of M. cornuarietis into freshwater ecosystems is primarily associated with pet/ domestic aquarium trade and subsequent wild release/escape of specimens (Howells et al., 2006; Rawlings et al., 2007). A further pathway for spread is the aquatic plants trade to pond gardening, with snails and their eggs accidentally distributed along with their host plants.
Pathway CausesTop of page
|Aquaculture||Associated with aquatic plants||Yes||Yes|
|Biological control||Introduced to various countries for control of snail intermediate hosts of Schistoma parasites, and||Yes||Yes|
|Escape from confinement or garden escape||Potential for escape from garden ponds, for example in cases of flood transporting snails into water||Yes|
|Flooding and other natural disasters||Potential for dispersal in the advent of a flood, transporting snails throughout waterways||Yes|
|Garden waste disposal||Yes|
|Horticulture||Associated with aquatic plants||Yes||Yes|
|Interconnected waterways||Associated with flood debris, especially that of dislodged aquatic plants||Yes|
|Landscape improvement||Associated with aquatic plants||Yes||Yes|
|Nursery trade||Associated with aquatic plants||Yes||Yes|
|Research||Widely utilized internationally as laboratory experiment animals||Yes||Yes|
Pathway VectorsTop of page
|Clothing, footwear and possessions||Eggs and snails potentially transported on clothing and equipment used in aquatic sports||Yes|
|Floating vegetation and debris||Eggs and snails associated with water transported vegetation debris||Yes|
|Host and vector organisms||Eggs and snails associated with traded aquatic plants||Yes|
|Pets and aquarium species||Yes||Yes|
|Plants or parts of plants||Associated with aquatic plants||Yes||Yes|
|Ship hull fouling||Eggs and/or snails attached to hull in vessels operating in reshwater systems||Yes|
Plant TradeTop of page
|Plant parts not known to carry the pest in trade/transport|
|Growing medium accompanying plants|
|Stems (above ground)/Shoots/Trunks/Branches|
Impact SummaryTop of page
|Cultural/amenity||Positive and negative|
|Economic/livelihood||Positive and negative|
Economic ImpactTop of page
M. cornuarietis is sold in the aquarium trade and therefore has an economic impact but the value of this is unknown. Until recently M. cornuarietis was released as a biocontrol agent for aquatic weeds and pulmonate snails (hosts of Schistosoma) (Radke et al., 1961; Schuytema, 1977; Pointier, 1999; Pointier, 2001). As a biological control agent of aquatic macrophytes, M. cornuarietis offered economic benefits in irrigation canals, drainage canals and in inland waterways important for freight movement and a reduction in the need for active weed management (Horne et al., 1992). However, the use of M. cornuarietis in biological control programmes is no longer considered an environmentally acceptable.
The principal agricultural crop that may be adversely impacted by M. cornuarietis is Oryza sativa (paddy rice) (Ortiz-Torres, 1962). Seedling rice plants may be killed by feeding, especially when there is no other source of food but the occurrence of this is low (Ortiz-Torres, 1962; Seaman and Porterfield, 1964).
Environmental ImpactTop of page
Herbivory by M. cornuarietis in recreational and amenity waterbodies may reduce the need for active aquatic weed control. Such an effect of M. cornuarietis has been observed in Lake Landa in Texas, USA (Horne et al., 1992) and is consistent with observations of dramatic declines in aquatic macrophyte biomass following deliberate introductions of M. cornuarietis into waterbodies in various Caribbean and African countries (Jobin, 1970; Jobin et al., 1973; Nguma et al., 1982; Frandsen, 1987; Pointier et al., 1991; Pointier, 1999; Pointier and David, 2004).
However, M. cornuarietis feeds predominantly on living macrophytes. This diet, coupled with their large body mass, high reproductive output and often high densities mean these snails can effect rapid changes in macrophyte community structure, with consequent perturbations of nutrient balance, turbidity and trophic structure of water bodies (Horgan et al., 2014). These effects are likely most adverse in freshwater ecosystems where the native invertebrate food webs were primarily dominated by detritivores and thus where herbivorous macro-invertebrates were naturally uncommon. The effects on macrophyte community structure can, however, be expected to be density dependent (Jobin, 1970; Jobin et al., 1973; Nguma et al., 1982; Frandsen 1987; Pointier et al., 1991; Pointier, 1999; Pointier and David, 2004). For example, adventive M. cornuarietis populations in the southern USA exhibit high annual variations in density (Howells et al., 2006), with adverse effects on macrophytes when the population density becomes high (Horne et al., 1992; Howells et al., 2006). M. cornuarietis exhibits a broad macrophyte host range. Nonetheless, impacts are likely also to vary with macrophyte identity as M. cornuarietis can exhibit strong feeding preferences (Cedeno-Leon and Thomas, 1982; Grantham et al., 1993; Morrison and Hay, 2011) such that some macrophyte species will be strongly defoliated while others will suffer few effects.
Changes in aquatic macrophyte communities can have a significant effect on native aquatic species which utilise macrophytes as a habitat, food or oviposition sites. This potential has been adequately demonstrated for pulmonate species in biological control programmes utilizing M. cornuarietis as the control agent. Nonetheless, there have been few studies that examine the impact of habitat perturbations by M. cornuarietis on native species.
In Texas, M. cornuarietis is having a negative impact by reducing cover and spawning habitat of the endangered fountain darter, Etheostoma fonticola (Horne et al., 1992; Bonner and McDonald, 2005). A study by Phillips et al. (2010) provided evidence that M. cornuarietis predates on the eggs of E. fonticola. In addition to this, Zizania texana (Texas wild rice), confined to the upper San Marcos River, is threatened by the loss and degradation of its habitat (NatureServe, 2015). Herbivory by M. cornuarietis has not specifically been listed as a threatening process, although Neck (1984) suggested that it could adversely the species.
There is clear evidence that apple snails, including M. cornuarietis, are involved as intermediate hosts of trematode parasites and may therefore spread the parasite onto native species (Nasir et al., 1968; Nasir et al., 1969; Mattos et al., 2013; Pinto et al., 2015).
Threatened SpeciesTop of page
|Threatened Species||Conservation Status||Where Threatened||Mechanism||References||Notes|
|Etheostoma fonticola (fountain darter)||No Details||Texas||Competition||Bonner and McDonald, 2005; Horne et al., 1992|
|Zizania texana (Texas wild-rice)||USA ESA listing as endangered species||Texas||Herbivory/grazing/browsing||NatureServe, 2015|
Risk and Impact FactorsTop of page Invasiveness
- Proved invasive outside its native range
- Has a broad native range
- Highly adaptable to different environments
- Is a habitat generalist
- Tolerant of shade
- Capable of securing and ingesting a wide range of food
- Highly mobile locally
- Has propagules that can remain viable for more than one year
- Altered trophic level
- Damaged ecosystem services
- Ecosystem change/ habitat alteration
- Host damage
- Modification of natural benthic communities
- Modification of nutrient regime
- Modification of successional patterns
- Negatively impacts agriculture
- Reduced native biodiversity
- Threat to/ loss of endangered species
- Threat to/ loss of native species
- Negatively impacts trade/international relations
- Competition - monopolizing resources
- Rapid growth
- Highly likely to be transported internationally accidentally
- Highly likely to be transported internationally deliberately
- Difficult/costly to control
UsesTop of page
M. cornuarietis occurs widely in aquaria but the economic value of this is unknown.
The species is also widely used as model organism in scientific laboratories and in education due to its wide availability through the aquaria trade and ease of culture. The species has been utilised in a range of studies that include anatomy, ontogeny and development, physiology, reproductive biology and environmental toxicology.
M. cornuarietis was introduced into some areas for control of pulmonate snails (principally in families Planorbidae, Physidae and Lymnaeidae) that function as intermediate hosts of trematode parasites affecting humans and/or their livestock (Demian and Luffy, 1964; Msangi and Kihauli, 1972; Jobin et al., 1973; Nguma et al., 1982; Pointier et al., 1991; Pointier, 1999; Pointier and David, 2004; Pointier and Jourdane, 2000). The primary interest has been on control of pulmonate snails involved in transmission of Schistosoma trematodes that cause schistomiasis in humans, but several studies have examined control of Lymnaeidae as intermediate hosts of Fasciola hepatica, the liver fluke parasite of ungulates. The reduction in submerged aquatic macrophytes was considered a factor in reducing population densities of pulmonate snails that are depend on macrophytes for food, cover and oviposition sites. Although resistant to infection with Schistosoma species, M. cornuarietis may serve as a decoy for schistosome miracidia which are attached but fail to penetrate (Combes and Moné, 1987). Madsen (1990) concluded that “although there is evidence that some snail species may effectively compete with schistosome vector species under certain circumstances, there are limitations to their use, since their habitat preferences may only partially overlap with those of the intermediate hosts.” The use of M. cornuarietis for biocontrol has not been fully established and is no longer encouraged.
M. cornuarietis has been evaluated experimentally and advocated as a biological control agent for macrophyte weeds in aquatic ecosystems and pulmonate snails. However, use of M. cornuarietis for such purposes is no longer promoted in recognition of the species’ adverse environmental impacts (Secor, 2014).
Uses ListTop of page
- Biological control
- Laboratory use
- Pet/aquarium trade
- Research model
Detection and InspectionTop of page
Detection of M. cornuarietis involves physical searching for egg masses or snails, amongst submerged aquatic macrophytes to about 1m depth in still to slow-flowing freshwater systems. Due to their large size adult M. cornuarietis snails do not present difficulties for detection, although they may be confused with the great ramshorn snail (Planorbarius corneus). M. cornuarietis egg masses and juvenile snails by way of their much smaller size are more difficult to detect, particularly when associated with large quantities of aquatic plant material. The eggs of M. cornuarietis differ from the brightly coloured, hard-shell eggs of most apple snails (Ampullariidae) in that they are translucent and suspended in numbers within a clear jelloid mass. The may however be confused with the eggs of pulmonate snails of families Physidae, Planorbidae and Lymnaeidae.
Similarities to Other Species/ConditionsTop of page
M. cornuarietis is similar in appearance to the closely related M. planogyra. However, M. planogyra is smaller at about 30 mm shell size, is more strongly planispiral, with both dorsal and ventral (umbilical) aspects strongly concave and openly perspective.
M.cornuarietis superficially resembles Planorbarius corneus because of the planispiral coiling of the shell. P. corneus is readily distinguished from M.cornuarietis in growing only to 35-40 mm shell size, the shell sinistral (left-coiling), shell lacking spiral colour bands, having the mantle cavity sealed but for a small contractile opening (pnuemostome), in being hermaphroditic with male and female reproductive organs within each individual, the male genitalia contained within the body cavity and only apparent externally when everted during copulation, lacking labial tentacles on the snout and lacking an operculum. The spawn of both species are similar, but embryos of P. corneus are reddish. Furthermore, while the hatchlings of both species are globose in shape, those of P. corneus lack an elevated spire.
Prevention and ControlTop of page
Due to the variable regulations around (de)registration of pesticides, your national list of registered pesticides or relevant authority should be consulted to determine which products are legally allowed for use in your country when considering chemical control. Pesticides should always be used in a lawful manner, consistent with the product's label.
In recognition of the potential adverse effects on commercial crops, native vegetation and natural ecosystems of high conservation and ecosystem service values, a number of countries and states have imposed restrictions of importation, possession and movement of some or all species of the family Ampullariidae. The United States Department of Agriculture, Animal and Plant Health Inspection Service (USDA-APHIS), implemented regulations in 2006 to require importers and inter-state sellers of marine and freshwater aquatic snails to obtain a three-year permit; prohibit the importation or interstate movement of all members of the Family Ampullariidae (excluding Pomacea bridgesi, P. diffusa and Asolene spixi) and require routine inspection of shipments of aquatic plants and aquarium supplies that may contain aquatic snails. Additional regulations apply in some US states. For example, in Texas, M. cornuarietis was added to the Texas Parks and Wildlife Department (TPWD) list of harmful or potentially harmful aquatic species in 1990. This legally prohibits possession, culture, sale and transport of this species. Ampullariidae are not prohibited or restricted in the State of Florida. Commercial aquaculturists culturing aquatic snails must annually acquire an Aquaculture Certificate of Registration from the Florida Department of Agriculture and Consumer Services, report the species they are culturing, include their certificate number on invoices and packaging and implement Aquaculture Best Management Practices. From August 2013, all species of Ampullariidae have been included in the Spanish legislation (Royal Decree 630/2013) as invasive species and listed in the Catálogo Español de Especies Exóticas Invasoras. Listing demands that procedures are in place to prevent introduction and establishment in Spain and its European territories. In the Australian state of New South Wales, Condition 47 of the Plant Quarantine Manual (NSW Department of Primary Industries, 2016) states “Any snail of the family Ampullariidae (Pilidae), including the golden apple snail (Pomacea canaliculata) are prohibited entry into the Rice Pest and Disease Exclusion Zone (RPDEZ).”
It may be possible to physically remove larger individuals from incipient populations but once reproduction has occurred (indicated by presence of eggs and/or juveniles) then eradication is unlikely.
Eradication of M. cornuarietis is theoretically possible by application of molluscicides over several years. Given that it is nonetheless very difficult to achieve 100% mortality due to differential susceptibility of individuals in populations and that likely rapid population resurgence from survivors and hatch from eggs may occur, repeat applications are required.
ReferencesTop of page
Aardt WJvan; Kock KNDe, 1991. Oxygen consumption and haemocyanin function in the freshwater snail Marisa cornuarietis (L). Comparative Biochemistry and Physiology, 10A:413-418.
Aguayo CG; Jaume ML, 1954. Mimeographed Edition. Habana, Cuba 725 pp.
Agudo-Padrón AI, 2009. Recent terrestrial and freshwater molluscs of Rio Grande do Sul State, RS, southern Brazil region: a comprehensive synthesis and check list. Visaya, April:1-13.
Appleton CC; Miranda NAF, 2015. Two Asian freshwater snails newly introduced into South Africa and an analysis of alien species reported to date. African Invertebrates, 56(1):1-17. http://www.bioone.org/loi/afin
Arias A; Torralba-Burrial A, 2014. First European record of the giant ramshorn snail Marisa cornuarietis (Linnaeus, 1758) (Gastropoda: Ampullariidae) from northern Spain. Limnetica, 33(1):65-72.
Aufderheide J; Warbritton R; Pounds N; File-Emperador S; Staples C; Caspers N; Forbes V, 2006. Effects of husbandry parameters on the life-history traits of the apple snail, Marisa cornuarietis: effects of temperature, photoperiod, and population density. Invertebrate Biology, 125(1):9-20. http://www.blackwell-synergy.com/servlet/useragent?func=showIssues&code=ivb
Bass D, 2003. A survey of freshwater macroinvertebrates in Tobago. Living World Journal of the Trinidad and Tobago Field Naturalists' Club:64-68.
Bass D, 2006. A comparison of the freshwater macroinvertebrate assemblages of St. Kitts and Nevis, West Indies. Living World Journal of Trinidad and Tobago Field Naturalists' Club:30-37.
Bio-West Inc, 2005. Comprehensive and critical period monitoring program to evaluate the effects of variable flow on biological resources in the San Marcos Springs/River aquatic ecosystem. Final 2004 report. Prepared for the Edwards Aquifer Authority. Bio-West, Inc. Pflugerville, Texas, USA: Bio-West Inc.
Bonner TH; McDonald DL, 2005. Threatened fishes of the world: Etheostoma fonticola (Jordan & Gilbert 1886) (Percidae). Environmental Biology of Fishes, 73:333-334.
Bowler PA; Frest TJ, 1992. The non-native snail fauna of the Middle Snake River, Southern Idaho. Proceedings of the Desert Fishes Council, 23:28-44.
Cazzaniga NJ; Estebenet AL, 1984. [English title not available]. (Revisión y notas sobre los hábitos alimentarios de los Ampullariidae (Gastropoda).) Historia Natural, 22:213-224.
Cedeno-Leon A; Thomas JD, 1982. Competition between Biomaphalaria glabrata (Say) and Marisa cornuarietis (L.): feeding niches. Journal of Applied Ecology, 19:707-721.
Chapman VJ; Brown JMA; Hill CF; Carr JL, 1974. Biology of excessive weed growth in the hydro-electric lakes of the Waikato River, New Zealand. Hydrobiologia, 44:349-363.
Charles L, 2009. A contribution to the knowledge of land and freshwater Mollusca of Grenada (Lesser Antilles). Survey report May 1-14 2009., Grenada: inistry of Agriculture, Lands, Forestry, Fisheries, public Utilities and Energy, and Société d'Histoire Naturelle l'Herminier.
Chi L; Winkler LR; Colvin R, 1971. Predation of Marisa cornuarietis on Oncomelania formosana eggs under laboratory conditions. The Veliger, 14:184-186.
Cowie RH; Hayes KA, 2012. Apple snails. In: A handbook of global freshwater invasive species [ed. by Francis, R. A.]. London, UK: Earthscan, 207-217.
Cowie RH; Thiengo SC, 2003. The apple snails of the Americas (Mollusca: Gastropoda: Ampullariidae: Asolene, Felipponea, Marisa, Pomacea, Pomella): a nomenclatural and type catalog. Malacologia, 45(1):41-100.
Damme Dvan; Ghamizi M; Soliman G; McIvor A; Seddon MB, 2010. The status and distribution of freshwater molluscs. In: The status and distribution of freshwater biodiversity in northern Africa [ed. by Garcia, N. \Cuttelod, A. \Malak, A. D.]. 29-114.
Demian ES; Kamel EG, 1972. Growth and population dynamics of Bulinus truncatus under semi-field conditions in Egypt. Proceedings of the Egytian Academy of Science, 25:37-60.
Demian ES; Kamel EG, 1973. Biological control of Bulinus truncatus under semifield conditions using the snail Marisa cornuarietis. In: International Congress on Tropical Medicine and Malaria (9th), Athens, 14-21 October, 1973. Volume II. Abstracts of communications. Athens., Greece 77-78.
Demian ES; Luffy RG, 1964. Prospects of the use of Marisa cornuarietis in the biological control of Lymnaea caillaudi in the UAR. Proceedings of the Egypt Academy of Science, 18:46-50.
Demian ES; Luffy RG, 1966. Factors affecting the predation of Marisa cornuarietis on Bulinus truncatus, Biomphalaria alexandrina and Lymnaea caillaudi. Oikos, 17:212-230.
Demian ES; Lutfy RG, 1965. Predatory activity of Marisa cornuaríetis against Bulinus (Bultnus) truncatus, the transmitter of urinary schistosomiasis. Annals of Tropical Medicine and Parasitology, 59(3):331-336.
Department of Primary Industries NSW, 2016. Plant quarantine manual for New South Wales. New South Wales, Australia: Plant Product Integrity & Standards Unit, NSW Department of Primary Industries Orange, 112 pp.
Dillon RT, 2000. The ecology of freshwater molluscs. Cambridge, UK: Cambridge University Press.
Dillon RT, 2003. The inheritance of golden, a shell color variant of Marisa cornuarietis. Malacological Review, 31/32:155-157.
Dipnarine T, 2015. Marisa cornuartietis (Giant Ramshorn Snail). The Online Guide to the Animals of Trinidad and Tobago. St Augustine, Trinidad and Tobago: University of West Indies. https://sta.uwi.edu/fst/lifesciences/documents/Marisa_cornuarietis.pdf
Dundee D, 1974. Catalog of introduced molluscs of eastern North America (North of Mexico). Sterkiana, 55:1-37.
Edmondson WT, 1959. Fresh-water biology, 2nd Edition. New York, USA: John Wiley and Sons.
El-Gaddal AA, 1988. Control of the Schistosoma mansoni and S. haematobium intermediate hosts in ricefields. In: Vector-borne disease control in humans through rice agroecosystem management. Proceedings of the Workshop on Research and Training Needs in the Field of Integrated Vector-borne Disease Control in Riceland Agroecosystems of Developing Countries, 9-14 March 1987 [ed. by Smith, W. H.]. Manila, Philippines: International Rice Research Institute, 211-215.
Ferguson FF, 1977. The role of biological agents in the control of schistosome-bearing snails. Atlanta, Geogria, USA: U.S. Department of Health, Education and Welfare, Public Health Service, Center for Disease Control,, 107 pp.
Ferguson FF; Butler JM, 1966. Proceeding of the Southern Weed Conference, 19. 468-476.
Ferguson FF; Palmer JR, 1958. Biological notes on Marisa corniuarietis, a predator of Australorbis glabratus, the snail intermediate host of schistosomiasis in Puerto Rico. American Journal of TropicalMedicine and Hygiene, 7:640-642.
Fernndez A; Franke S; Sigarreta S; Salazar R, 2006. New records of freshwater mollusks in the Oriental North Region of Holgun and Las Tunas Provinces, Cuba. Of Sea and Shore, 27(2):153-155.
Ferrer Lopez JR; Moné H; Perera de Puga G; Cong MY, 1991. Role of Marisa cornuarietis as a biological control agent and its economic and epidemiological implications. (Rol de Marisa cornuarietis como agente de control biológico y sus implicaciones económicas y epidemiológicas.) Revista Cubana de Medicina Tropical, 43(1):31-35.
Fimia Duarte R; Vázquez Perera AA; Rodríguez YL; Cepero Rodríguez O; Pereira Marin CA, 2010. Freshwater malacofauna of medical importance located in Yaguajay municipality, Sancti Spíritus province. (Malacofauna fluviátil con importancia médica en el municipio Yaguajay, Sancti Spíritus.) Revista Cubana de Medicina Tropical, 62(1):11-17. http://scielo.sld.cu/scielo.php?script=sci_arttext&pid=S0375-07602010000100002&lng=en&nrm=iso&tlng=es
Frandsen F; 1987, publ. 1988. Control of schistosomiasis by use of biological control of snail hosts with special reference to competition. In: Memórias do Instituto Oswaldo Cruz, 82(Suppl. 4). 129-133.
Freiburg MW; Hazelwood DH, 1977. Oxygen consumption of two amphibious snails: Pomacea paludosa and Marisa cornuarietus (Prosobranchia: Ampullariidae). Malacologia, 16(2):541-548.
Frest TJ; Bowler PA, 1992. A preliminary checklist of the aquatic and terrestrial mollusks of the Middle Snake River Sub-Basin. Proceedings of the Desert Fishes Council, 24:52-58.
Frest TJ; Johannes EJ, 2000. An annotated checklist of the Idaho land and freshwater mollusks. Journal of the Idaho Academy of Science, 36(2):1-51.
Geijskes DC; Pain T, 1957. Suriname freshwater snails of the genus Pomacea. Studies on the fauna of Suriname and other Guyanas, 1(3):41-48.
Grantham Ö; Moorhead DL; Willig MR, 1993. Feeding preference of an aquatic gastropod, Marisa cornuarietis: effects of pre-exposure. Journal of the North American Benthological Society, 12:431-437.
Gutiérrez A; Perera G; Yong M; Fernandez JA, 1997. Relationships of the prosobranch snails Pomacea paludosa, Tarebia granifera and Melanoides tuberculata with the abiotic environment and freshwater snail diversity in the central region of Cuba. Malacological Review, 30:39-44.
Hale MC, 1964. Thesis. Coral Gables, Florida, USA: University of Miami.
Haridi AAM; Jobin WR, 1985. Estimated risks and benefits from introducing Marisa cornuarietis into the Sudan. Journal of Tropical Medicine and Hygiene [[The Blue Nile Health Project. A comprehensive approach to the prevention and control of water-associated diseases in irrigated schemes of the Sudan.].], 88(2):145-151.
Haridi AAM; Safi El; Jobin WR, 1985. Survival, growth and reproduction of the imported ampularid snail Marisa cornuarietis in central Sudan. Journal of Tropical Medicine and Hygiene, 88:135-144.
Hofkin BV; Stryker GA; Koech DK; Loker ES, 1991. Consumption of Biomphalaria glabrata egg masses and juveniles by the ampullariid snails Pila ovata, Lanistes carinatus and Marisa cornuarietis.. Acta Tropica, 49(1):37-44.
Horgan FG; Stuart AM; Kudavidanage EP, 2014. Impact of invasive apple snails on the functioning and services of natural and managed wetlands. Acta Oecologica [Ecosystem impacts of invasive species. BIOLIEF 2011 - 2nd World Conference on Biological Invasion and Ecosystem Functioning, Mar del Plata, Argentina, 21-24 November 2011.], 54:90-100. http://www.sciencedirect.com/science/journal/1146609X
Horne FR; Arsuffi TL; Neck RW, 1992. Recent introduction and potential botanical impact of the giant rams-horn snail, Marisa cornuarietis (Pilidae), in the Comal Springs ecosystem of central Texas. The Southwestern Naturalist, 37(2):194-214.
Howells R, 2001. Introduced non-native fishes and shellfishes in Texas waters: an updated list and discussion. Introduced non-native fishes and shellfishes in Texas waters: an updated list and discussion. unpaginated. [Texas Parks and Wildlife Department, Management Data Series No. 188.]
Howells RG; Burlakova LE; Karatayev AY; Marfurt RK; Burks RL, 2006. Native and introduced ampullariidae in North America: history, status, and ecology. In: Global advances in ecology and management of golden apple snails [ed. by Joshi, R. C.\Sebastian, L. S.]. Los Baños, Philippines: Philippine Rice Research Institute (PhilRice), 73-112.
Hunt BP, 1958. Introduction of Marisa into Florida. The Nautilus, 72:53-55.
Hunt BP, 1961. Tolerance of a fresh-water snail, Marisa cornuarietis L. to sea water. Quarterly Journal of the Florida Academy of Science, 23:278-284.
Ihering Hvon, 1919. [English title not available]. (Las especies de Ampullaria en la República Argentina y la historia del Río de la Plata.) Sociedad Argentina de Ciencias Naturales:329-350.
Jobin WR; Ferguson FF; Berrios-Duran LA, 1973. Effects of Marisa cornuarietis on populations of B. glabrata in farm ponds in Puerto Rico. American Journal of Tropical Medicine and Hygiene, 22:278-284.
Kairo M; Ali B; Cheesman O; Haysom K; Murphy S, 2003. Invasive species threats in the Caribbean region. Report to the Nature Conservancy. Curepe, Trinidad and Tobago: CAB International, 132 pp. http://www.issg.org/database/species/reference_files/Kairo%20et%20al,%202003.pdf
Karatayev AY; Burlakova LE; Karatayev VA; Padilla DK, 2009. Introduction, distribution, spread, and impacts of exotic freshwater gastropods in Texas. Hydrobiologia, 619:181-194. http://springerlink.metapress.com/content/1573-5117/
Keller RP; Drake JM; Lodge DM, 2007. Fecundity as a basis for risk assessment of nonindigenous freshwater molluscs. Conservation Biology, 21(1):191-200. http://www.blackwell-synergy.com/doi/pdf/10.1111/j.1523-1739.2006.00563.x
Lutfy RG; Demian ES, 1965. Studies on the chromosome numbers in the Ampullariidae (Gastropoda, Prosobranchiata). Proceedings of the Egyptian Academy of Sciences, 18:34-49.
Massemin D; Lamy D; Pointier J-P; Gargominy O, 2009. [English title not available]. (Coquillages et escargots de Guyane.) Collection Parthénope. Paris, France: Muséum national d'Histoire naturelle, 456 pp.
Mattos ACde; Boaventura MFF; Fernandez MA; Thiengo SC, 2013. Larval trematodes in freshwater gastropods from Mato Grosso, Brazil: diversity and host-parasites relationships. Biota Neotropica, 13(4):34-38. http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1676-06032013000400034&lng=en&nrm=iso&tlng=en
Meier-Brook C, 1978. Calcium uptake by Marisa cornuarietis (Gastropoda: Ampullariidae), a predator of schistosome-bearing snails. Archiv für Hydrobiologie, 82:449-64.
Michelson EH; Augustine DL; 1957, Apr. Studies on the Biological Control of Schistosome-Bearing Snails. Y. The Control of Biomphalaria pfeifferi Populations by the Snail, Marisa cornuarietis, under Laboratory Conditions. Journal of Parasitology, 43(2):135.
Milstein D; Mienis HK; Rittner O, 2012. A field guide to the molluscs of inland waters of the Land of Israel. Jerusalem, Israel: Israel Nature and National Parks Protection Authority, 54 pp.
Morrison WE; Hay ME, 2011. Feeding and growth of native, invasive and non-invasive alien apple snails (Ampullariidae) in the United States: invasives eat more and grow more. Biological Invasions, 13(4):945-955. http://www.springerlink.com/content/511320h258vj3h25/
Msangi AS; Kihauli PM, 1972. Prospects of biological control of schistosomes in East Africa. In: Parasitoses of Man and Animals in Africa [ed. by Anderson, C. \Kilama, W. L.]. 439-446.
Nasir P; Hamana SLJ; Dfaz MT, 1969. Studies on freshwater larval trematodes. XXIII. Additional five new species of Venezuelan cercariae. Proceedings of the Helminthological Society of Washington, 36(2):231-239.
National Institute of Water and Atmospheric Research (NIWA), 2002. Weed management., New Zealand: National Institute of Water and Atmospheric Research. https://www.niwa.co.nz/our-science/aquatic-biodiversity-and-biosecurity/our-services/aquaticplants/outreach/weedman/control
NatureServe, 2015. NatureServe Explorer: An online encyclopedia of life (Version 7.1). Arlington, Virginia, USA: NatureServe. http://explorer.natureserve.org
Neck RW, 1984. Occurrence of the striped ram's horn snail, Marisa cornuarietis, in central Texas (Ampullariidae). The Nautilus, 98:119-120.
Ng TH; Tan SK; Low MEY, 2014. Singapore Mollusca: 7. The family Ampullariidae (Gastropoda: Caenogastropoda: Ampullarioidea). Nature in Singapore, 7:31-47.
Ng TingHui; Tan SiongKat; Wong WingHing; Meier R; Chan SowYan; Tan HeokHui; Yeo DCJ, 2016. Molluscs for sale: Assessment of freshwater gastropods and bivalves in the ornamental pet trade. PLoS ONE, 11(8):e0161130. http://dx.doi.org/10.1371/journal.pone.0161130
Nguma JFM; McCullough FS; Masha E, 1982. Elimination of Biomphalaria pfeifferi, Bulinus tropicus and Lymnaea natalensis by the ampullarid snail, Marisa cornuarietis, in a man-made dam in northern Tanzania. Acta Tropica, 39(1):85-90.
OECD, 2010. Detailed review paper (DRP) on mollusc life-cycle toxicity testing. OECD Environment, Health and Safety Publications Series on Testing and Assessment No. 121. ENV/JM/MONO(2010) 9. Paris, France: Organisation for Economic Co-operation and Development.
Oliver-Gonzales J; Bauman PM; Benenson AS, 1956. Effect of the snail Marisa cornuarietus on Australorbis glabratus in natural bodies of water in Puerto Rico. American Journal of Tropical Medicine and Hygiene, 5:290-296.
Ortiz-Torres E, 1962. Damage caused by the snail, Marisa cornuarietis, to young rice seedlings in Puerto Rico. Journal of Agriculture, University of Puerto Rico, 46:241.
Peebles CR; Oliver-Gonzalez J; Ferguson FF, 1972. Apparent adverse effect of Marisa cornuarietis upon Lymnaea columella and Biomphalaria glabrata in an ornamental pond in Puerto Rico. Proceedings of the Hawaiian Entomological Society, 21:247-256.
Perera G; Walls JG, 1996. Apple Snails in the Aquarium. Neptune City, New Jersey, USA: T.F.H. Publications, Inc, 121 pp.
Phillips T; Alexander ML; Howard R, 2010. Consumption of eggs of the endangered fountain darter (Etheostoma fonticola) by native and nonnative snails. The Southwestern Naturalist, 55(1):115-117.
Pinto HA; Cantanhede SPD; Thiengo SC; Melo ALde; Fernandez MA, 2015. The apple snail Pomacea maculata (Caenogastropoda: Ampullariidae) as the intermediate host of Stomylotrema gratiosus (Trematoda: Stomylotrematidae) in Brazil: the first report of a mollusc host of a stomylotrematid trematode. Journal of Parasitology, 101(2):134-139. http://www.bioone.org/loi/para
Pointier JP, 2001. Invading freshwater snails and biological control in Martinique Island, French West Indies. Memórias do Instituto Oswaldo Cruz [7th International symposium on schistosomiasis, Rio de Janeiro, Brazil, 5-9 December 1999.], 96(Supplement):67-74.
Pointier J-P, 2015. Freshwater molluscs of Venezuela and their medical and veterinary importance. Harxheim, Germany: ConchBooks, 228 pp.
Pointier JP; David P, 2004. Biological control of Biomphalaria glabrata, the intermediate host of schistosomes, by Marisa cornuarietis in ponds of Guadeloupe: long-term impact on the local snail fauna and aquatic flora. Biological Control, 29(1):81-89.
Pointier J-P; Yong M; Gutirrez A, 2005. Guide to the freshwater Molluscs of Cuba. Hackenheim, Germany: ConchBooks, 120 pp.
Quintana MG, 1982. [English title not available]. (Catalogo preliminar de la malacofauna del Paraguay.) Revista del Museo Argentino de Ciencias Natureles "Bernardino Rivadivia" e Instituto Nacion de Investigacion de las Ciencias Natureles, Zoologia, 11(3):61-158.
Radke MG; Ritchie LS; ; Ferguson FF, 1961. Demonstrated control of Australorbis glabatus by Marisa cornuarietis under field conditions in Puerto Rico. American Journal of Tropical Medicine and Hygiene, 10:370-373.
Ramírez R; Paredes C; Arenas J, 2003. [English title not available]. (Moluscos del Perú.) Revista de Biología Tropical (Suppl 3):225-284.
Rawlings TA; Hayes KA; Cowie RH; Collins TM, 2007. The identity, distribution, and impacts of non-native apple snails in the continental United States. BMC Evolutionary Biology, 7(97):(26 June 2007). http://www.biomedcentral.com/content/pdf/1471-2148-7-97.pdf
Robins CH, 1971. Ecology of the introduced appel snail, Marisa cornuarietis (Ampullariidae) in Dade County, Florida. The Biologist, 53:136-152.
Roll U; Dayan T; Simberloff D; Mienis HK, 2009. Non-indigenous land and freshwater gastropods in Israel. Biological Invasions, 11(8):1963-1972. http://www.springerlink.com/content/77868kh054164441/fulltext.html
Santos CAZ; Penteado CHS; Mendes EG, 1987. The respiratory responses of an amphibious snail Pomacea lineata (Spix, 1827), to temperature and oxygen tension variations. Comparative Biochemistry and Physiology, 86A:409-415.
Selck H; Aufderheide J; Pounds N; Staples C; Caspers N; Forbes V, 2006. Effects of food type, feeding frequency, and temperature on juvenile survival and growth of Marisa cornuarietis (Mollusca: Gastropoda). Invertebrate Biology, 125(2):106-116.
Simone LRL, 2006. Land and freshwater molluscs of Brazil: an illustrated inventory on the Brazilian Malacolofauna, including neighbour regions of the South America, respect to the terrestrial and freshwater ecosystems., Brazil: Fundação de Amparo à Pesquisa do Estado de São Paulo, 390 pp.
Snyder NFR; Kale HW, 1983. Mollusk predation by snail kites in Colombia. The Auk, 100:93-97.
Stryker GA; Koech DK; Loker ES, 1991. Growth of Biomphalaria glabrata populations in the presence of the ampullariid snails Pila ovata, Lanistes carinatus and Marisa cornuarietis.. Acta Tropica, 49(2):137-147.
Taylor DW, 1993. [English title not available]. (Moluscos dulceacuícolas de Costa Rica: introducción y lista preliminar.) Revista de Biología Tropical, 41(3):653-655.
USGS NAS, 2016. USGS Nonindigenous Aquatic Species Database. Gainesville, Florida, USA: USGS. http://nas.er.usgs.gov/
Vázquez Perera AA; Perera Valderrama S, 2010. Endemic Freshwater molluscs of Cuba and their conservation status. Tropical Conservation Science, 3(2):190-199. http://tropicalconservationscience.mongabay.com/content/v3/10-06-28_190-199_Perera&Valderrama.pdf
Aardt WJvan, Kock KNDe, 1991. Oxygen consumption and haemocyanin function in the freshwater snail Marisa cornuarietis (L). In: Comparative Biochemistry and Physiology, 10A 413-418.
Aguayo CG, Jaume ML, 1954. Mimeographed Edition., Habana, Cuba: 725 pp.
Agudo-Padrón AI, 2009. Recent terrestrial and freshwater molluscs of Rio Grande do Sul State, RS, southern Brazil region: a comprehensive synthesis and check list. In: Visaya, 1-13.
Arias A, Torralba-Burrial A, 2014. First European record of the giant ramshorn snail Marisa cornuarietis (Linnaeus, 1758) (Gastropoda: Ampullariidae) from northern Spain. In: Limnetica, 33 (1) 65-72.
Bass D, 2003. A survey of freshwater macroinvertebrates in Tobago. In: Living World Journal of the Trinidad and Tobago Field Naturalists' Club, 64-68.
Bass D, 2006. A comparison of the freshwater macroinvertebrate assemblages of St. Kitts and Nevis, West Indies. In: Living World Journal of Trinidad and Tobago Field Naturalists' Club, 30-37.
Bowler PA, Frest TJ, 1992. The non-native snail fauna of the Middle Snake River, Southern Idaho. [Proceedings of the Desert Fishes Council], 23 28-44.
CABI, Undated. Compendium record. Wallingford, UK: CABI
CABI, Undated a. CABI Compendium: Status inferred from regional distribution. Wallingford, UK: CABI
CABI, Undated b. CABI Compendium: Status as determined by CABI editor. Wallingford, UK: CABI
Charles L, 2009. A contribution to the knowledge of land and freshwater Mollusca of Grenada (Lesser Antilles). In: Survey report May 1-14 2009, Grenada, Ministry of Agriculture, Lands, Forestry, Fisheries, public Utilities and Energy, and Société d'Histoire Naturelle l'Herminier.
Cowie RH, Hayes KA, 2012. Apple snails. In: A handbook of global freshwater invasive species, [ed. by Francis R A]. London, UK: Earthscan. 207-217.
Cowie RH, Thiengo SC, 2003. The apple snails of the Americas (Mollusca: Gastropoda: Ampullariidae: Asolene, Felipponea, Marisa, Pomacea, Pomella): a nomenclatural and type catalog. In: Malacologia, 45 (1) 41-100.
Damme Dvan, Ghamizi M, Soliman G, McIvor A, Seddon MB, 2010. The status and distribution of freshwater molluscs. In: The status and distribution of freshwater biodiversity in northern Africa, [ed. by Garcia N, Cuttelod A, Malak AD]. 29-114.
Demian E S, Kamel E G, 1973. Biological control of Bulinus truncatus under semifield conditions using the snail Marisa cornuarietis. In: International Congress on Tropical Medicine and Malaria (9th), Athens, 14-21 October, 1973. Volume II. Abstracts of communications. [International Congress on Tropical Medicine and Malaria (9th), Athens, 14-21 October, 1973. Volume II. Abstracts of communications.], Athens. Greece: 77-78.
Dipnarine T, 2015. Marisa cornuartietis (Giant Ramshorn Snail). In: The Online Guide to the Animals of Trinidad and Tobago, St Augustine, Trinidad and Tobago: University of West Indies. https://sta.uwi.edu/fst/lifesciences/documents/Marisa_cornuarietis.pdf
Dundee DS, 1974. Catalog of introduced molluscs of eastern North America (North of Mexico). In: Sterkiana, 55 1-37.
Edmondson WT, 1959. Fresh-water biology., New York, USA: John Wiley and Sons.
Ferguson F F, Richards C S, Sebastian S T, Buchanan I C, 1960. Natural abatement of schistosomiasis mansoni in St. Kitts, British West Indies. Public Health. 74 (7), 261-265. DOI:10.1016/S0033-3506(60)80083-2
Fernndez A, Franke S, Sigarreta S, Salazar R, 2006. New records of freshwater mollusks in the Oriental North Region of Holgun and Las Tunas Provinces, Cuba. In: Of Sea and Shore, 27 (2) 153-155.
Ferrer Lopez J R, Moné H, Perera de Puga G, Cong M Y, 1991. Role of Marisa cornuarietis as a biological control agent and its economic and epidemiological implications. (Rol de Marisa cornuarietis como agente de control biológico y sus implicaciones económicas y epidemiológicas.). Revista Cubana de Medicina Tropical. 43 (1), 31-35.
Frest TJ, Bowler PA, 1992. A preliminary checklist of the aquatic and terrestrial mollusks of the Middle Snake River Sub-Basin. [Proceedings of the Desert Fishes Council], 24 52-58.
Frest TJ, Johannes EJ, 2000. An annotated checklist of the Idaho land and freshwater mollusks. In: Journal of the Idaho Academy of Science, 36 (2) 1-51.
Gutiérrez A, Perera G, Yong M, Fernandez JA, 1997. Relationships of the prosobranch snails Pomacea paludosa, Tarebia granifera and Melanoides tuberculata with the abiotic environment and freshwater snail diversity in the central region of Cuba. In: Malacological Review, 30 39-44.
Hale MC, 1964. Thesis., Coral Gables, Florida, USA: University of Miami.
Horgan F G, Stuart A M, Kudavidanage E P, 2014. Impact of invasive apple snails on the functioning and services of natural and managed wetlands. Acta Oecologica. 90-100. http://www.sciencedirect.com/science/journal/1146609X DOI:10.1016/j.actao.2012.10.002
Horne FR, Arsuffi TL, Neck RW, 1992. Recent introduction and potential botanical impact of the giant rams-horn snail, Marisa cornuarietis (Pilidae), in the Comal Springs ecosystem of central Texas. In: The Southwestern Naturalist, 37 (2) 194-214.
Howells R G, Burlakova L E, Karatayev A Y, Marfurt R K, Burks R L, 2006. Native and introduced ampullariidae in North America: history, status, and ecology. In: Global advances in ecology and management of golden apple snails. [ed. by Joshi R C, Sebastian L S]. Los Baños, Philippines: Philippine Rice Research Institute (PhilRice). 73-112.
Howells R, 2001. Introduced non-native fishes and shellfishes in Texas waters: an updated list and discussion. In: Introduced non-native fishes and shellfishes in Texas waters: an updated list and discussion, unpaginated.
Hunt BP, 1958. Introduction of Marisa into Florida. In: The Nautilus, 72 53-55.
Ihering Hvon, 1919. [English title not available]. (Las especies de Ampullaria en la República Argentina y la historia del Río de la Plata). In: Sociedad Argentina de Ciencias Naturales, 329-350.
Jobin W R, Brown R A, Velez S P, Ferguson F F, 1977. Biological control of Biomphalaria glabrata in major reservoirs of Puerto Rico. American Journal of Tropical Medicine and Hygiene. 26 (5), 1018-1024.
Kairo M, Ali B, Cheesman O, Haysom K, Murphy S, 2003. Invasive species threats in the Caribbean region. Report to the Nature Conservancy. In: Invasive species threats in the Caribbean region. Report to the Nature Conservancy. Curepe, Trinidad and Tobago: CAB International. 132 pp. http://www.issg.org/database/species/reference_files/Kairo%20et%20al,%202003.pdf
Karatayev A Y, Burlakova L E, Karatayev V A, Padilla D K, 2009. Introduction, distribution, spread, and impacts of exotic freshwater gastropods in Texas. Hydrobiologia. 181-194. http://springerlink.metapress.com/content/1573-5117/ DOI:10.1007/s10750-008-9639-y
Milstein D, Mienis HK, Rittner O, 2012. A field guide to the molluscs of inland waters of the Land of Israel., Jerusalem, Israel: Israel Nature and National Parks Protection Authority. 54 pp.
Msangi AS, Kihauli PM, 1972. Prospects of biological control of schistosomes in East Africa. In: Parasitoses of Man and Animals in Africa, [ed. by Anderson C, Kilama WL]. 439-446.
Neck RW, 1984. Occurrence of the striped ram's horn snail, Marisa cornuarietis, in central Texas (Ampullariidae). In: The Nautilus, 98 119-120.
Nguma J F M, McCullough F S, Masha E, 1982. Elimination of Biomphalaria pfeifferi, Bulinus tropicus and Lymnaea natalensis by the ampullarid snail, Marisa cornuarietis, in a man-made dam in northern Tanzania. Acta Tropica. 39 (1), 85-90.
Oliver-Gonzales J, Bauman PM, Benenson AS, 1956. Effect of the snail Marisa cornuarietus on Australorbis glabratus in natural bodies of water in Puerto Rico. In: American Journal of Tropical Medicine and Hygiene, 5 290-296.
Perera G, Walls JG, 1996. Apple Snails in the Aquarium., Neptune City, New Jersey, USA: T.F.H. Publications, Inc. 121 pp.
Pointier J P, 1999. Invading freshwater gastropods: some conflicting aspects for public health. In: Malacologia [Proceedings of Unitas Malacologica-American Malacological Society symposium: Interactions between man and molluscs, 26-30 July 1998, Washington, D.C., USA.], 41 (2) [ed. by Davis G M]. 403-411.
Pointier J P, 2001. Invading freshwater snails and biological control in Martinique Island, French West Indies. Memórias do Instituto Oswaldo Cruz. 96 (Supplement), 67-74. DOI:10.1590/S0074-02762001000900009
Pointier J P, Augustin D, 1999. Biological control and invading freshwater snails. A case study. Comptes Rendus de l'Académie des Sciences. Série III, Sciences de la Vie. 322 (12), 1093-1098. DOI:10.1016/S0764-4469(99)00108-0
Pointier J P, David P, 2004. Biological control of Biomphalaria glabrata, the intermediate host of schistosomes, by Marisa cornuarietis in ponds of Guadeloupe: long-term impact on the local snail fauna and aquatic flora. Biological Control. 29 (1), 81-89. DOI:10.1016/S1049-9644(03)00137-3
Pointier J P, Théron A, Imbert-Establet D, Borel G, 1991. Eradication of a sylvatic focus of Schistosoma mansoni using biological control by competitor snails. Biological Control. 1 (3), 244-247. DOI:10.1016/1049-9644(91)90073-9
Pointier JP, 2015. Freshwater molluscs of Venezuela and their medical and veterinary importance., Harxheim, Germany: ConchBooks. 228 pp.
Pointier J-P, Yong M, Gutirrez A, 2005. Guide to the freshwater Molluscs of Cuba., Hackenheim, Germany: ConchBooks. 120 pp.
Quintana MG, 1982. [English title not available]. ((Catalogo preliminar de la malacofauna del Paraguay.) Revista del Museo Argentino de Ciencias Natureles "Bernardino Rivadivia" e Instituto Nacion de Investigacion de las Ciencias Natureles). In: Zoologia, 11 (3) 61-158.
Ramírez R, Paredes C, Arenas J, 2003. [English title not available]. (Moluscos del Perú). In: Revista de Biología Tropical, 225-284.
Rawlings T A, Hayes K A, Cowie R H, Collins T M, 2007. The identity, distribution, and impacts of non-native apple snails in the continental United States. BMC Evolutionary Biology. 7 (97), (26 June 2007). http://www.biomedcentral.com/content/pdf/1471-2148-7-97.pdf
Robins CH, 1971. Ecology of the introduced appel snail, Marisa cornuarietis (Ampullariidae) in Dade County, Florida. In: The Biologist, 53 136-152.
Roll U, Dayan T, Simberloff D, Mienis H K, 2009. Non-indigenous land and freshwater gastropods in Israel. Biological Invasions. 11 (8), 1963-1972. http://www.springerlink.com/content/77868kh054164441/fulltext.html DOI:10.1007/s10530-008-9373-4
Simone LRL, 2006. Land and freshwater molluscs of Brazil: an illustrated inventory on the Brazilian Malacolofauna, including neighbour regions of the South America, respect to the terrestrial and freshwater ecosystems., Brazil: Fundação de Amparo à Pesquisa do Estado de São Paulo. 390 pp.
Taylor DW, 1993. [English title not available]. (Moluscos dulceacuícolas de Costa Rica: introducción y lista preliminar). In: Revista de Biología Tropical, 41 (3) 653-655.
USGS NAS, 2016. USGS Nonindigenous Aquatic Species Database., Gainesville, Florida, USA: USGS. http://nas.er.usgs.gov/
Vázquez Perera A A, Perera Valderrama S, 2010. Endemic Freshwater molluscs of Cuba and their conservation status. Tropical Conservation Science. 3 (2), 190-199. http://tropicalconservationscience.mongabay.com/content/v3/10-06-28_190-199_Perera&Valderrama.pdf
Principal SourceTop of page
Draft datasheet under review
ContributorsTop of page
03/11/2016 Original text by:
Gary M. Barker, Consultant, Australia.
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