''Indoplanorbis'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...
of air-breathing
freshwater snail
Freshwater snails are gastropod mollusks which live in fresh water. There are many different families. They are found throughout the world in various habitats, ranging from ephemeral pools to the largest lakes, and from small seeps and springs ...
. Its
only member species is ''Indoplanorbis exustus'', an
aquatic pulmonate
Pulmonata or pulmonates, is an informal group (previously an order, and before that a subclass) of snails and slugs characterized by the ability to breathe air, by virtue of having a pallial lung instead of a gill, or gills. The group includ ...
gastropod
The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda ().
This class comprises snails and slugs from saltwater, from freshwater, and from land. T ...
mollusk
Mollusca is the second-largest phylum of invertebrate animals after the Arthropoda, the members of which are known as molluscs or mollusks (). Around 85,000 extant species of molluscs are recognized. The number of fossil species is e ...
in the
family
Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...
Planorbidae
Planorbidae, common name the ramshorn snails or ram's horn snails, is a family of air-breathing freshwater snails, aquatic pulmonate gastropod molluscs. Unlike most molluscs, the blood of ram's horn snails contains iron-based hemoglobin instea ...
, the
ram
Ram, ram, or RAM may refer to:
Animals
* A male sheep
* Ram cichlid, a freshwater tropical fish
People
* Ram (given name)
* Ram (surname)
* Ram (director) (Ramsubramaniam), an Indian Tamil film director
* RAM (musician) (born 1974), Dutch
* ...
's horn snails. The species is widely distributed across the tropics. It serves as an important
intermediate host
In biology and medicine, a host is a larger organism that harbours a smaller organism; whether a parasitic, a mutualistic, or a commensalist ''guest'' (symbiont). The guest is typically provided with nourishment and shelter. Examples include a ...
for several
trematode
Trematoda is a class of flatworms known as flukes. They are obligate internal parasites with a complex life cycle requiring at least two hosts. The intermediate host, in which asexual reproduction occurs, is usually a snail. The definitive host ...
parasites.
The
invasive nature and ecological tolerance of ''Indoplanorbis exustus'' add to its importance in veterinary and medical science.
Taxonomy
''Indoplanorbis exustus'' is the only known species in the genus ''Indoplanorbis''. In spite of its long history and wide geographical range, it is thought that ''Indoplanorbis'' includes only a single species.
However
phylogeography
Phylogeography is the study of the historical processes that may be responsible for the past to present geographic distributions of genealogical lineages. This is accomplished by considering the geographic distribution of individuals in light of ge ...
research by Liu et al. (2010)
revealed the phylogenetic depth of divergences between the Indian clades and Southeast Asian clades, together with habitat and parasitological differences suggest that ''Indoplanorbis exustus'' may comprise more than one species.
The most phylogenetically related genus to ''Indoplanorbis'' is genus ''
Bulinus
''Bulinus'' is a genus of small tropical freshwater snails, aquatic gastropod mollusks in the family Bulinidae, the ramshorn snails and their allies. MolluscaBase eds. (2020). MolluscaBase. Bulinus O. F. Müller, 1781. Accessed through: World ...
''.
Distribution
The freshwater snail ''Indoplanorbis exustus'' is found across
Iran
Iran, officially the Islamic Republic of Iran, and also called Persia, is a country located in Western Asia. It is bordered by Iraq and Turkey to the west, by Azerbaijan and Armenia to the northwest, by the Caspian Sea and Turkmeni ...
,
Nepal,
India
India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...
,
Sri Lanka
Sri Lanka (, ; si, ශ්රී ලංකා, Śrī Laṅkā, translit-std=ISO (); ta, இலங்கை, Ilaṅkai, translit-std=ISO ()), formerly known as Ceylon and officially the Democratic Socialist Republic of Sri Lanka, is an ...
, Southeast Asia (for example
Thailand
Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...
),
central Asia (
Afghanistan
Afghanistan, officially the Islamic Emirate of Afghanistan,; prs, امارت اسلامی افغانستان is a landlocked country located at the crossroads of Central Asia and South Asia. Referred to as the Heart of Asia, it is bordere ...
), Arabia and Africa.
The type locality of ''Indoplanorbis exustus'' is marshes on the coast of
Malabar
Malabar may refer to the following:
People
* Malabars, people originating from the Malabar region of India
* Malbars or Malabars, people of Tamil origin in Réunion
Places
* Malabar Coast, or Malabar, a region of the southwestern shoreline o ...
in southwestern India.
''Indoplanorbis exustus'' is a common snail across Southeast Asia and the Indian sub-continent.
The snail is also found in the Middle East (
Oman
Oman ( ; ar, عُمَان ' ), officially the Sultanate of Oman ( ar, سلْطنةُ عُمان ), is an Arabian country located in southwestern Asia. It is situated on the southeastern coast of the Arabian Peninsula, and spans the mouth of t ...
and
Socotra
Socotra or Soqotra (; ar, سُقُطْرَىٰ ; so, Suqadara) is an island of the Republic of Yemen in the Indian Ocean, under the ''de facto'' control of the UAE-backed Southern Transitional Council, a secessionist participant in Yemen’s ...
) and
Nigeria
Nigeria ( ), , ig, Naìjíríyà, yo, Nàìjíríà, pcm, Naijá , ff, Naajeeriya, kcg, Naijeriya officially the Federal Republic of Nigeria, is a country in West Africa. It is situated between the Sahel to the north and the Gulf o ...
and the Ivory Coast;
these findings were attributed by Brandt (1974) to recent introductions by human activities (Brandt's view has been frequently cited in the literature on ''Indoplanorbis'').
[Brown D. S. (1994). ''Freshwater snails of Africa and their medical importance''. London: Taylor & Francis. 20]
208
[.] In contrast to Asia, the well documented appearance of the snail in Africa (e.g., Nigeria
abstract
and Ivory Coast) and more recently (2002) in the Lesser Antilles,
is almost certainly the result of introductions through human activities over the last 50–100 years.
This species is already established in the US, and is considered to represent a potentially serious threat as a
pest, an
invasive species
An invasive species otherwise known as an alien is an introduced organism that becomes overpopulated and harms its new environment. Although most introduced species are neutral or beneficial with respect to other species, invasive species ad ...
which could negatively affect agriculture, natural ecosystems, human health or commerce. Therefore, it has been suggested that this species be given top national
quarantine
A quarantine is a restriction on the movement of people, animals and goods which is intended to prevent the spread of disease or pests. It is often used in connection to disease and illness, preventing the movement of those who may have been ...
significance in the US.
Biogeography
Meier-Brook (1984) adopted an African (
Gondwana
Gondwana () was a large landmass, often referred to as a supercontinent, that formed during the late Neoproterozoic (about 550 million years ago) and began to break up during the Jurassic period (about 180 million years ago). The final stages ...
n) origin for ''Indoplanorbis'' with rafting to Asia since the
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of th ...
on the northward migrating
Indian craton
The geology of India is diverse. Different regions of India contain rocks belonging to different geologic periods, dating as far back as the Eoarchean Era. Some of the rocks are very deformed and altered. Other deposits include recently d ...
; this author also considered a Europe to Southwest Asia tract or an Africa to South India dispersal.
Morgan et al. (2002) attributed the occurrence of ''Indoplanorbis'' in India to colonization (from Africa) via the Middle East land connection.
Clearly the two different dispersal mechanisms imply very different chronologies; the Gondwanan vicariance hypothesis implies that proto-''Indoplanorbis'' has been present in India since the late Eocene (35 Ma; India: Asia collision), whereas dispersal via
the
Sinai-Levant suggests a Plio-
Pleistocene
The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...
arrival.
The results by Liu et al. (2010) indicated a radiation beginning in the late Miocene with a divergence of an ancestral bulinine lineage into
Assam
Assam (; ) is a state in northeastern India, south of the eastern Himalayas along the Brahmaputra and Barak River valleys. Assam covers an area of . The state is bordered by Bhutan and Arunachal Pradesh to the north; Nagaland and Manipur ...
and peninsular India clades.
A Southeast Asian clade diverged from the peninsular India clade late-Pliocene; this clade then radiated at a much more rapid pace to colonize all of the sampled range of ''Indoplanorbis'' in the mid-Pleistocene.
Description
The
shell
Shell may refer to:
Architecture and design
* Shell (structure), a thin structure
** Concrete shell, a thin shell of concrete, usually with no interior columns or exterior buttresses
** Thin-shell structure
Science Biology
* Seashell, a hard o ...
of this species, like all planorbids is sinistral in coiling, but is carried upside down and thus appears to be dextral. The shell of ''Indoplanorbis exustus'' is discoid with rapidly increasing
whorls
A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs).
Whorls in nature
File:Photograph and axial plane floral ...
.
Each whorl is higher than it is wide.
The width of the shell is 5
–25 mm.
The height of the shell is 4.5
–13 mm.
''
Planorbella duryi
''Planorbella duryi'', common name the Seminole rams-horn, is a species of air-breathing freshwater snail, a pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails. The species is endemic to Florida and is found frequently ...
'' and ''
Biomphalaria pfeifferi
''Biomphalaria pfeifferi'' is a species of air-breathing freshwater snail, an aquatic animal pulmonate gastropod mollusk in the family Planorbidae, the ram's horn snails.
This snail is a medically important pest, because of transferring the ...
'' have similar shells.
Because of its wide distribution, various aspects of ''Indoplanorbis exustus'' have been studied, such as its calcium regulation and its
hemocyte
A blood cell, also called a hematopoietic cell, hemocyte, or hematocyte, is a cell produced through hematopoiesis and found mainly in the blood. Major types of blood cells include red blood cells (erythrocytes), white blood cells (leukocytes), a ...
s.
Ecology
In captivity ''Indoplanorbis exustus'' can be reared on
lettuce
Lettuce (''Lactuca sativa'') is an annual plant of the family Asteraceae. It is most often grown as a leaf vegetable, but sometimes for its stem and seeds. Lettuce is most often used for salads, although it is also seen in other kinds of food, ...
and
spinach
Spinach (''Spinacia oleracea'') is a leafy green flowering plant native to central and western Asia. It is of the order Caryophyllales, family Amaranthaceae, subfamily Chenopodioideae. Its leaves are a common edible vegetable consumed either f ...
.
Its diet is sometimes supplemented with sheep's
liver
The liver is a major Organ (anatomy), organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of proteins and biochemicals necessary for ...
and it can be given rat food to prepare for breeding.
abstract
Habitat
The snail is found in small ponds, pools, and less commonly in
rice paddy fields.
The snail may also occur in semi-permanent pools formed in flooded areas of fields, where it can survive the dry season buried in mud.
The
desiccation tolerance Desiccation tolerance refers to the ability of an organism to withstand or endure extreme dryness, or drought-like conditions. Plants and animals living in arid or periodically arid environments such as temporary streams or ponds may face the challe ...
of adult snails is high, while the resistance of juvenile snails is very low. Consequently, dispersal may occur in clumps of mud adhered to the bodies of cattle or across water in vegetation mats. It is possible it could be transported by birds.
Life cycle
''Indoplanorbis exustus'' is a
hermaphroditic
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes.
Many taxonomic groups of animals (mostly invertebrates) do not have separ ...
invasive snail species with high
fecundity
Fecundity is defined in two ways; in human demography, it is the potential for reproduction of a recorded population as opposed to a sole organism, while in population biology, it is considered similar to fertility, the natural capability to pr ...
.
Within one year of introduction the snail is able to colonize habitats with well established populations of other pulmonate and prosobranch snails.
The snail requires a water temperature in excess of 15 °C for maturation.
At the optimum temperature of 30 °C each snail can lay up to 800 eggs.
There is from 2 to 43 eggs in one cluster with an average 20 eggs in one cluster.
The capacity for self-fertilization and high fecundity probably underlies the invasive potential of the species.
The average life span of ''Indoplanorbis exustus'' is 4 months
and during this time it lays about 60 egg clusters.
Predators
Eggs of ''Indoplanorbis exustus'' were experimentally predated and destroyed by ''
Pomacea bridgesii
''Pomacea bridgesii'', common names the spike-topped apple snail or mystery snail, is a South American species of freshwater snail with gills and an operculum, an aquatic gastropod mollusk in the family Ampullariidae. These snails were mos ...
''.
Raut & Aditya (2002) hypothetized that ''Pomacea bridgesii'' could be a potential
biocontrol
Biological control or biocontrol is a method of controlling pests, such as insects, mites, weeds, and plant diseases, using other organisms. It relies on predation, parasitism, herbivory, or other natural mechanisms, but typically also invo ...
agent for ''Indoplanorbis exustus''.
Parasites
''Indoplanorbis'' is of economic importance in that it is responsible for the transmission of several species of the genus ''
Schistosoma
''Schistosoma'' is a genus of trematodes, commonly known as blood flukes. They are parasitic flatworms responsible for a highly significant group of infections in humans termed '' schistosomiasis'', which is considered by the World Health Organ ...
'' which infect cattle and cause reduced
livestock
Livestock are the domesticated animals raised in an agricultural setting to provide labor and produce diversified products for consumption such as meat, eggs, milk, fur, leather, and wool. The term is sometimes used to refer solely to animals ...
productivity.
The snail is also of medical importance as a source of
cercarial dermatitis
Swimmer's itch, cercarial dermatitis or schistosome dermatitis is a short-term allergic contact dermatitis occurring in the skin of humans that have been infected by water-borne schistosomes, a type of flatworm. It is common in freshwater, bracki ...
among rural workers, particularly in India.
''Indoplanorbis exustus'' is best known as the intermediate host responsible for the
transmission
Transmission may refer to:
Medicine, science and technology
* Power transmission
** Electric power transmission
** Propulsion transmission, technology allowing controlled application of power
*** Automatic transmission
*** Manual transmission
*** ...
of ''
Schistosoma nasale
''Schistosoma nasale'' is a species of digenetic trematode in the family Schistosomatidae. ''S. nasale'' inhabits blood vessels of the nasal mucosa and causes " snoring disease" in cattle, but remains symptomless in buffaloes though extruding it ...
'' and ''
S. spindale'', as well as other trematodes such as ''
Echinostoma
''Echinostoma'' is a genus of trematodes (flukes), which can infect both humans and other animals. These intestinal flukes have a three-host life cycle with snails or other aquatic organisms as intermediate hosts, and a variety of animals, inc ...
'' spp. and some
spirorchids.
A third species of ''Schistosoma'', ''
S. indicum'' (Montgomery, 1906), is also transmitted by ''I. exustus''.
Other snails have been implicated in transmission of these three ''Schistosoma'' species (such as ''
Lymnaea luteola
''Radix luteola'' is a species of freshwater snail, an aquatic gastropod mollusc in the family Lymnaeidae.
Placement of this species within the genus ''Radix'' was confirmed by Correa et al. (2010).Correa C. A., Escobar J. S., Durand P., Ren ...
'', a host for ''S. indicum'' and ''S. nasale'', and ''
L. acuminata'', a host for ''S. nasale'' and ''S. spindale''), ''I. exustus'' is the most important host for ''S. nasale'' and ''S. spindale'', as well as for ''S. indicum'' in certain regions. ''I. exustus'' may be the sole natural intermediate host for these three ''Schistosoma'' species on the Indian sub-continent.
''Indoplanorbis exustus'' is also an intermediate host for:
* ''
Artyfechinostomum malayanum'' – as the first intermediate host
* ''
Hypoderaeum conoideum'' – as the first intermediate host
* ''
Fasciola gigantica
''Fasciola gigantica'' is a parasitic flatworm of the class Trematoda, which causes tropical fascioliasis. It is regarded as one of the most important single platyhelminth infections of ruminants in Asia and Africa. Estimates of infection rates ...
''
[
* '' Paramphistomum mehrai''][
* '' Paramphistomum explanatum''][
* '' Gastrodiscus secundus''][
* '' Petagifer srivastavi''][
* '' Plasmiorchis orientalis''][
* '' Pseudodiscus collinsi''][
* '' Gastrothylax crumenifer''][
* '' Enterohaemotrema paleorticum''][
* '' Cotylophoron cotylophorum''][
* '' Cotylophoron indica''][
* '' Cotylophoron bhaleraoi''][
* '' Cotylophoron mathurapurensis''][
''Indoplanorbis exustus'' has been implicated in outbreaks of ]cercarial dermatitis
Swimmer's itch, cercarial dermatitis or schistosome dermatitis is a short-term allergic contact dermatitis occurring in the skin of humans that have been infected by water-borne schistosomes, a type of flatworm. It is common in freshwater, bracki ...
in human populations in India, Laos, Malaysia and Thailand. Cercarial dermatitis results from the cutaneous allergic reaction
Allergies, also known as allergic diseases, refer a number of conditions caused by the hypersensitivity of the immune system to typically harmless substances in the environment. These diseases include hay fever, food allergies, atopic derma ...
in people exposed to larval schistosomes (cercariae
Trematodes are parasitic flatworms of the class ''Trematoda'', specifically parasitic flukes with two suckers: one ventral and the other oral. Trematodes are covered by a tegument, that protects the organism from the environment by providing secr ...
) shed by infected snails into freshwater bodies such as lakes, ponds, and paddy fields. The cercariae cause pruritus
Itch (also known as pruritus) is a sensation that causes the desire or reflex to scratch. Itch has resisted many attempts to be classified as any one type of sensory experience. Itch has many similarities to pain, and while both are unpleasant ...
(itching) and papular eruptions, with often severe secondary infections, as they attempt to infect a non-permissive definitive host and die in the skin.
Toxicology
Aqueous extract of a common medicinal plant of India ''Euphorbia tithymaloides
''Euphorbia tithymaloides'' is a perennial succulent spurge. An erect shrub,Vardhana, ''Direct Uses of Medicinal Plants and Their Identification'', 2008, p. 261. the plant is also known by the scientific name ''Pedilanthus tithymaloides''. Howev ...
'' (Euphorbiaceae
Euphorbiaceae, the spurge family, is a large family of flowering plants. In English, they are also commonly called euphorbias, which is also the name of a genus in the family. Most spurges, such as ''Euphorbia paralias'', are herbs, but some, e ...
) has molluscicidal
Molluscicides () – also known as snail baits, snail pellets, or slug pellets – are pesticides against molluscs, which are usually used in agriculture
Agriculture or farming is the practice of cultivating plants and livestock. Agricul ...
activity against ''Indoplanorbis exustus''.
Ethanol extract of '' Solanum xanthocarpum'' has molluscicidal activity against ''Indoplanorbis exustus'' LC50 = 198.00 mg/L and LC90 = 236.80 mg/L.
The latex of ''Euphorbia milii
''Euphorbia milii'', the crown of thorns, Christ plant, or Christ thorn, is a species of flowering plant in the spurge family Euphorbiaceae, native to Madagascar. The species name commemorates Baron Milius, once Governor of Réunion, who introdu ...
'' has molluscicidal activity against ''Indoplanorbis exustus'' that depends on its hybrid of the plant.
The molluscicidal activity of latex of '' Cascabela thevetia'', ''Alstonia scholaris
''Alstonia scholaris'', commonly called blackboard tree, Scholar Tree, Milkwood or devil's tree in English, is an evergreen tropical tree in the Dogbane Family (Apocynaceae). It is native to southern China, tropical Asia (mainly the Indian subcon ...
'' and ''Euphorbia pulcherrima
The poinsettia ( or ) (''Euphorbia pulcherrima'') is a commercially important flowering plant species of the diverse spurge family Euphorbiaceae. Indigenous to Mexico and Central America, the poinsettia was first described by Europeans in 1834 ...
'' against ''Indoplanorbis exustus'' was examined by Singh & Sunil (2005).[.]
Human use
It is a part of ornamental pet trade
Wildlife trade refers to the of products that are derived from non-domesticated animals or plants usually extracted from their natural environment or raised under controlled conditions. It can involve the trade of living or dead individuals, ti ...
for freshwater aquaria.
References
This article incorporates CC-BY-2.0 text from the reference.[.]
External links
* Baker F. C. (1945). ''The molluscan family Planorbidae''. The University of Illinois Press, Urbana
196
201.
* Raut S. K. (1986). "Disease transmitting snails. II. Population studies of ''Indoplanorbis exustus'' Deshayes." First year PRS Thesis in Science, University of Calcutta.
*
* .
*
{{Taxonbar, from1=Q18585564, from2=Q3791090
Monotypic mollusc genera
Bulinidae