Bulinus

{{Short description|Genus of gastropods}} {{Use dmy dates|date=June 2020}} {{Automatic taxobox | image = Bulinus wrighti.png | image_caption = ''Bulinus wrighti'' | taxon = Bulinus | authority = O. F. Müller, 1781<ref>Müller O. F. 1781. ''Geschichte der Perlen-Blasen''. Der Naturforscher 15: 1-20, Tab. I [= 1]. Halle.</ref> | display_parents = 2 | diversity_ref = <ref name="memorias.ioc.fiocruz.br">[http://memorias.ioc.fiocruz.br/93sup1/15cob.html ''Characterisation of Bulinus''] {{Webarchive|url=https://web.archive.org/web/20070328120717/http://memorias.ioc.fiocruz.br/93sup1/15cob.html# |date=28 March 2007 }}. Accessed 31 December 2008.</ref> | diversity_link = #Species | diversity = 37 extant species, at least 7 fossil species | synonyms_ref = <ref name="Neubauer 2017">{{Cite journal| doi = 10.1093/mollus/eyx015| pages = 1–9| last1 = Neubauer| first1 = Thomas A.| last2 = Mandic| first2 = Oleg| last3 = Harzhauser| first3 = Mathias| last4 = Jovanović| first4 = Gordana| title = The discovery of Bulinus (Pulmonata: Planorbidae) in a Miocene palaeolake in the Balkan Peninsula| journal = Journal of Molluscan Studies| volume=83| year=2017| issue = 3| doi-access = free}}</ref> | synonyms = {{hidden begin|title = List}} * ''Bulinus'' (''Bulinus'') O. F. Müller, 1781 * ''Bulinus'' (''Isidora'') Ehrenberg, 1831 * ''Bulinus'' (''Physopsis'') F. Krauss, 1848 * ''Bulinus'' (''Pyrgophysa'') Crosse, 1879 * ''Bullinus'' Oken, 1815 [lapsus] * ''Bulinus'' (''Isidora'') Ehrenberg, 1831 * ''Isidora'' Ehrenberg, 1831 * ''Isidora'' (''Physopsis'') F. Krauss, 1848 * †''Kosovia'' Atanacković, 1959 * †''Kosovia'' (''Kosovia'') Atanacković, 1959 * ''Limnaea'' (''Bulinus'') O.F. Müller, 1781 * ''Physa'' (''Bulinus'') O.F. Müller, 1781 * ''Physa'' (''Isidora'') Ehrenberg, 1831 * ''Physa'' (''Pyrgophysa'') Crosse, 1879 * ''Physopsis'' F. Krauss, 1848 * ''Pulmobranchia'' Pelseneer, 1894 * ''Pyrgophysa'' Crosse, 1879 {{hidden end}} }}

'''''Bulinus''''' is a genus of small tropical freshwater snails, aquatic gastropod mollusks in the family Bulinidae, the ramshorn snails and their allies.<ref name="WoRMS">MolluscaBase eds. (2020). MolluscaBase. Bulinus O. F. Müller, 1781. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=224352 on 2020-06-27</ref>

This genus is medically important because several species of ''Bulinus'' function as intermediate hosts for the schistosomiasis blood fluke.<ref name="Kane 2008">{{Cite journal | last1 = Kane | first1 = R. A. | last2 = Stothard | first2 = J. R. | last3 = Emery | first3 = A. M. | last4 = Rollinson | first4 = D. | title = Molecular characterization of freshwater snails in the genus Bulinus: A role for barcodes? | doi = 10.1186/1756-3305-1-15 | journal = Parasites & Vectors | volume = 1 | page = 15 | year = 2008 | issue = 1 | pmid = 18544153| pmc =2441610 | doi-access = free }}</ref>

== Description == The shell of species in the genus ''Bulinus'' is sinistral. It has a very large body whorl and a small spire.

==Distribution and habitat== Species of the genus are widespread in Africa including Madagascar<ref>{{Cite journal | last1 = Stothard | first1 = J. R. | last2 = Brémond | first2 = P. | last3 = Andriamaro | first3 = L. | last4 = Sellin | first4 = B. | last5 = Sellin | first5 = E. | last6 = Rollinson | first6 = D. | title = Bulinus species on Madagascar: Molecular evolution, genetic markers and compatibility with Schistosoma haematobium | journal = Parasitology | volume = 123 Suppl | issue = 7 | pages = S261–S275 | year = 2001 | pmid = 11769288 | doi=10.1017/s003118200100806x | s2cid = 21584714 }}</ref> and the Middle East.<ref>{{Cite journal | last1 = Jørgensen | first1 = A. | last2 = Jørgensen | first2 = L. V. G. | last3 = Kristensen | first3 = T. K. | last4 = Madsen | first4 = H. | last5 = Stothard | first5 = J. R. | title = Molecular phylogenetic investigations of Bulinus (Gastropoda: Planorbidae) in Lake Malawi with comments on the topological incongruence between DNA loci | doi = 10.1111/j.1463-6409.2007.00298.x | journal = Zoologica Scripta | volume = 36 | issue = 6 | page = 577 | year = 2007 | s2cid = 85182925 }}</ref>

This genus has not yet become established in the USA, but it is considered to represent a potentially serious threat as a pest, an invasive species which could negatively affect agriculture, natural ecosystems, human health or commerce. Therefore it has been suggested that this species be given top national quarantine significance in the USA.<ref>Cowie R. H., Dillon R. T., Robinson D. G. & Smith J. W. (2009). "Alien non-marine snails and slugs of priority quarantine importance in the United States: A preliminary risk assessment". ''American Malacological Bulletin'' '''27''': 113-132. [http://dillonr.people.cofc.edu/Cowie-et-al-2009.pdf PDF] {{webarchive|url=https://web.archive.org/web/20160616175729/http://dillonr.people.cofc.edu/Cowie-et-al-2009.pdf |date=16 June 2016 }}.</ref>

The genus ''Bulinus'' has arguably the greatest and widespread distribution of all pulmonate snail species in the Afromontane regions. This can be attributed to its great ability to adapt and increase its range from freshwater ponds at sea-level to extreme altitudes as experienced on the "sky islands". A recent study has recently extended the range of ''Bulinus'' by 900 m to around 4,000 m on top of Mt. Elgon. Specifically, some of the places they can be found in include pools and wetlands marshes. They also can be found in standing or slow-moving (lentic) and running (lotic) waterbodies.<ref name=":3">{{Cite journal |last1=Tumwebaze |first1=I. |last2=Clewing |first2=C. |last3=Chibwana |first3=F. D. |last4=Kipyegon |first4=J. K. |last5=Albrecht |first5=C. |date=2022-05-17 |title=Evolution and Biogeography of Freshwater Snails of the Genus Bulinus (Gastropoda) in Afromontane Extreme Environments |journal=Frontiers in Environmental Science |language=English |volume=10 |doi=10.3389/fenvs.2022.902900 |doi-access=free |bibcode=2022FrEnS..1002900T |issn=2296-665X}}</ref>

It has been predicted that climate change has been the cause to changes in ''Bulinus'' species distribution. This has led to changes in endemism and evolutionary dynamics such as speciation and extinction.<ref name=":3" />

== Feeding strategies == ''Bulinus'' species are herbivorous freshwater snails that primarily graze on algae and detritus. They are classified as grazers, and their feeding habits play an important role in nutrient cycling and the overall ecosystem of freshwater habitats.<ref>{{Cite journal |last1=Mutsaka-Makuvaza |first1=Masceline Jenipher |last2=Zhou |first2=Xiao-Nong |last3=Tshuma |first3=Cremance |last4=Abe |first4=Eniola |last5=Manasa |first5=Justen |last6=Manyangadze |first6=Tawanda |last7=Allan |first7=Fiona |last8=Chinómbe |first8=Nyasha |last9=Webster |first9=Bonnie |last10=Midzi |first10=Nicholas |date=2020-01-10 |title=Molecular diversity of Bulinus species in Madziwa area, Shamva district in Zimbabwe: implications for urogenital schistosomiasis transmission |journal=Parasites & Vectors |volume=13 |issue=1 |page=14 |doi=10.1186/s13071-020-3881-1 |doi-access=free |issn=1756-3305 |pmc=6954605 |pmid=31924254}}</ref> They graze on biofilms that are composed of bacteria, fungi, and protozoans. They have a similar feeding mechanism to other freshwater gastropods, using their radula to scrape surfaces and ingest food. The radula is lined with rows of microscopic teeth.<ref>{{Cite web |title=Fulltext PDF: academicjournals/ijzr/2022/1-7.pdf |url=https://scialert.net/fulltext/fulltextpdf.php?pdf=academicjournals/ijzr/2022/1-7.pdf |access-date=2025-03-26 |website=scialert.net}}</ref>

== Dormancy == Seasonal droughts are common in the habitats of the ''Bulinus'' snails and it has long been a topic of discussion to scientists of how the snails are capable of enduring and aestivate through the long-lasting and harsh climates and weather cycles. Aestivation is common in snails, which is when the snail undergoes periodic dormancy due to decreased moisture in the environment. Studies towards snail dormancy have been halted due to the mystery of where ''Bulinus'' snails aestivate, which therefore complicate efforts into schistosomiasis disease prevention.<ref name=":1">{{Cite journal |last1=Starkloff |first1=Naima C. |last2=Mahalila |first2=Moses P. |last3=Kinung'hi |first3=Safari |last4=Civitello |first4=David J. |date=2024 |title=Resting in plain sight: Dormancy ecology of the intermediate snail host of Schistosoma haematobium |journal=Ecology |language=en |volume=105 |issue=12 |article-number=e4472 |doi=10.1002/ecy.4472 |issn=1939-9170 |pmc=11610713 |pmid=39561783|bibcode=2024Ecol..105E4472S }}</ref>

After up to seven months of dry season yearly, wet season brings the rapid reemergence of whole ''Bulinus'' snail populations who have been aestivating with decreased metabolism and many various physiological adaptations. It was also discovered that ''Bulinus'' snails delay egg-laying for about 2 weeks following aestivation.<ref name=":1" /> [[File:Bulinus tropicus shell 4.png|thumb|Sinistral shell of ''Bulinus tropicus'']]

== Invasive effects == ''Bulinus'' snails have become established as both an invasive species and an intermediate host of smaller invasive parasites that severely impact human health. Blood flukes are the parasite that latches on to these snails, causing them to indirectly transmit urinary schistosomiasis. An example can be seen in Zimbabwe, where ''Bulinus globosus'' is the primary vector for urinary schistosomiasis. Large outbreaks of blood flukes can occur in rural communities with untreated water.<ref>{{Cite journal |last1=Chandiwana |first1=S. K. |last2=Christensen |first2=N. O. |last3=Frandsen |first3=F. |date=December 1987 |title=Seasonal patterns in the transmission of Schistosoma haematobium, S. mattheei and S. mansoni in the highveld region of Zimbabwe |journal=Acta Tropica |volume=44 |issue=4 |pages=433–444 |issn=0001-706X |pmid=2894133}}</ref> Climate change has expanded the snails range, which has worsened the outbreaks.<ref>{{Cite journal |last1=Kalinda |first1=Chester |last2=Chimbari |first2=Moses J. |last3=Mukaratirwa |first3=Samson |date=2017-05-01 |title=Effect of temperature on the Bulinus globosus - Schistosoma haematobium system |journal=Infectious Diseases of Poverty |volume=6 |issue=1 |page=57 |doi=10.1186/s40249-017-0260-z |doi-access=free |issn=2049-9957 |pmc=5410706 |pmid=28457230}}</ref>

== Schistosomiasis transmission == [[File:Schistosomiasis_Lifecycle.png|thumb|Role of ''Bulinus'' in the life cycle of ''Schistosoma'' spp.]] Much of the importance of the ''Bulinus'' genus of snails comes from its role as an intermediate host for the disease schistosomiasis. It is vital to understand the epidemiology of the organisms that cause this disease (''Schistosoma'' species) in these snails to create effective plans and measures to control the transmission of schistosomiasis.<ref name=":2">{{Cite journal |last1=Justine |first1=Nyanda C. |last2=Mazigo |first2=Humphrey D. |last3=Fuss |first3=Antje |last4=Webster |first4=Bonnie L. |last5=Konje |first5=Eveline T. |last6=Brehm |first6=Klaus |last7=Mueller |first7=Andreas |date=2025-01-01 |title=Seasonal distribution and cercarial shedding of Bulinus spp. snails: Implications for urogenital schistosomiasis control in the Simiyu Region, northwestern Tanzania |journal=Current Research in Parasitology & Vector-Borne Diseases |volume=7 |article-number=100248 |doi=10.1016/j.crpvbd.2025.100248 |pmid=39989476 |pmc=11847301 |issn=2667-114X}}</ref> In Africa alone, at least 130 million people are affected by human urogenital schistosomiasis.<ref name=":32">{{Cite journal |last1=Tumwebaze |first1=I. |last2=Clewing |first2=C. |last3=Chibwana |first3=F. D. |last4=Kipyegon |first4=J. K. |last5=Albrecht |first5=C. |date=2022-05-17 |title=Evolution and Biogeography of Freshwater Snails of the Genus Bulinus (Gastropoda) in Afromontane Extreme Environments |journal=Frontiers in Environmental Science |language=English |volume=10 |doi=10.3389/fenvs.2022.902900 |doi-access=free |bibcode=2022FrEnS..1002900T |issn=2296-665X}}</ref>

In the transmission of ''S. haematobium'', ''Bulinus'' snails are infected through free-swimming miracidia stage of the parasite where the ''Bulinus'' snails facilitate the asexual reproduction of the flatworm. Cercariae are produced whom then seek out humans who are in water in which they infect and produce eggs which will be urinated and hatch into miracidia to continue the cycle of schistosomiasis infection.<ref name=":2" /> Learning the life cycle of both ''Bulinus'' and ''Schistosoma'' species is important because, in rural areas where agriculture is common industry, land is altered to increase agricultural water where ponds and networks of rain catchment become snail hotspots that have great potential to transmit schistosomiasis. There may also be an increase of susceptibility to schistosome transmission in snails following aestivation.<ref name=":12">{{Cite journal |last1=Starkloff |first1=Naima C. |last2=Mahalila |first2=Moses P. |last3=Kinung'hi |first3=Safari |last4=Civitello |first4=David J. |date=2024 |title=Resting in plain sight: Dormancy ecology of the intermediate snail host of Schistosoma haematobium |journal=Ecology |language=en |volume=105 |issue=12 |article-number=e4472 |doi=10.1002/ecy.4472 |issn=1939-9170 |pmc=11610713 |pmid=39561783|bibcode=2024Ecol..105E4472S }}</ref>

==Species== [[File:Bulinus truncatus.jpg|thumb|Lateral view of a shell of ''Bulinus truncatus''.]] Species within the genus ''Bulinus'' have been placed into four species groups: the ''Bulinus africanus'' group, ''Bulinus forskalii'' group, ''Bulinus reticulatus'' group and the ''Bulinus truncatus/tropicus'' complex.<ref name="Kane 2008"/> For the most part, species have been classified on the basis of their morphology although, in recent decades, the study of ploidy, allozymes and DNA methods have all played an increasing role in species discrimination.<ref name="Kane 2008"/> Morphological characters, whilst adequate to allocate a specimen to a species group are sometimes unreliable when used to classify at higher resolution especially within the ''Bulinus africanus'' group.<ref name="Kane 2008"/>

The following species are recognised in the genus ''Bulinus'':<ref>{{Cite web |title=WoRMS - World Register of Marine Species - Out of scope |url=https://www.marinespecies.org/aphia.php?p=taxdetails&id=224352 |access-date=2025-03-29 |website=www.marinespecies.org}}</ref>

;''Bulinus africanus'' group * ''Bulinus abyssinicus'' (Martens, 1866) * ''Bulinus africanus'' (Krauss, 1848) * ''Bulinus globosus'' (Morelet, 1866) * ''Bulinus hightoni'' Brown & Wright, 1978 * ''Bulinus jousseaumei'' (Dautzenberg, 1890) * ''Bulinus nasutus'' (Martens, 1879) * ''Bulinus obtusispira'' (Smith, 1882) * ''Bulinus obtusus'' Mandahl-Barth, 1973 * ''Bulinus ugandae'' Mandahl-Barth, 1954 * ''Bulinus umbilicatus'' Mandahl-Barth, 1973

;''Bulinus forskalii'' group * ''Bulinus barthi'' Jelnes, 1979 * ''Bulinus bavayi'' (Dautzenberg, 1894) * ''Bulinus beccarii'' (Paladilhe, 1872) * ''Bulinus browni'' Jelnes, 1979 * ''Bulinus camerunensis'' Mandahl-Barth, 1957 * ''Bulinus canescens'' (Morelet, 1868) * ''Bulinus crystallinus'' (Morelet, 1868) * ''Bulinus forskalii'' (Ehrenberg, 1831) * ''Bulinus scalaris'' (Dunker, 1845) * ''Bulinus senegalensis'' Müller, 1781 - the type species of the genus

;''Bulinus reticulatus'' group * ''Bulinus reticulatus'' Mandahl-Barth, 1954 * ''Bulinus wrighti'' Mandahl-Barth, 1965

;''Bulinus truncatus/tropicus'' complex * ''Bulinus angolensis'' (Morelet, 1866) * ''Bulinus depressus'' Haas, 1936 * ''Bulinus hexaploidus'' Burch, 1972 * ''Bulinus liratus'' (Tristram, 1863) * ''Bulinus mutandensis'' Preston, 1913<ref>{{cite iucn |author=Kyambadde, R. |year=2010 |title=''Bulinus mutandensis'' |volume=2010 |article-number=e.T44267A10884886 |doi=10.2305/IUCN.UK.2010-3.RLTS.T44267A10884886.en |access-date=28 September 2024}}</ref> * ''Bulinus natalensis'' (Küster, 1841) * ''Bulinus nyassanus'' (E. A. Smith, 1877) * ''Bulinus octoploidus'' Burch, 1972 * ''Bulinus permembranaceus'' (Preston, 1912) * ''Bulinus succinoides'' (E. A. Smith, 1877) * ''Bulinus transversalis'' (Martens, 1897) * ''Bulinus trigonus'' (Martens, 1892) *†''Bulinus trojanus'' {{small|(Neumayr, 1883)}} * ''Bulinus tropicus'' (Krauss, 1848) * ''Bulinus truncatus'' (Audouin, 1827) * ''Bulinus yemenensis'' Paggi et al., 1978

;Other * †''Bulinus arinus'' {{small|G.-X. Zhu, 1980}} * †''Bulinus banlashanensis'' {{small|X.-H. Yu, 1987}} * †''Bulinus bouei'' (Pavlović, 1931) - from late Miocene * †''Bulinus corici'' Harzhauser & Neubauer, 2012 - from middle Miocene * ''Bulinus dautzenbergi'' {{small|(Germain, 1905)}} * †''Bulinus dilatatus'' {{small|G.-X. Zhu, 1980}} * †''Bulinus fuxinensis'' {{small|X.-H. Yu, 1987}} * ''Bulinus indicus'' {{small|A. N. Subba Rao, Mitra, Parashar, G. P. Gupta & K. M. Rao, 1994}} * †''Bulinus kormosi'' {{small|Soós, 1934}} * † ''Bulinus matejici'' (Pavlović, 1931) - from middle Miocene * †''Bulinus ovaformis'' {{small|X.-H. Yu, 1987}} * † ''Bulinus pavlovici'' (Atanacković, 1959) - from late Miocene * †''Bulinus pijiagouensis'' {{small|X.-H. Yu, 1987}} * †''Bulinus stevanovici'' (Atanacković, 1959) - late Miocene * †''Bulinus striatus'' (Milošević, 1978) - late Miocene * †''Bulinus yushugouensis'' {{small|(G.-X. Zhu, 1976)}}

== References == {{Commons category|Bulinus}} This article incorporates CC-BY-2.5 text from the reference<ref name="Kane 2008"/> {{Reflist}}

Category:Bulinus Category:Taxa named by Otto Friedrich Müller