Hydrobiidae

Hydrobiidae, commonly known as mud snails, is a large cosmopolitan family of very small freshwater and brackish water snails with an operculum; they are in the order Littorinimorpha.
Distribution
Hydrobiidae are found in much of the world, inhabiting all continents except Antarctica. In Australia alone there are over 260 species in the family.
Description
These are very small or minute snails, with a shell height of less than 8 mm. The dextrally-coiled shells are smooth (except for growth lines conforming to the shape of the outer lip) and are usually rather nondescript. The shell offers very few robust characteristics to the systematist who is attempting to classify the species within this family. This difficulty is compounded by a high degree of intraspecific variation. Descriptions often have to be based on the characteristics of the operculum, radula and penis.
The shell of species within this family varies from planispiral to needle-shaped. The shell may have an open umbilicus or a plugged umbilicus. The thickness of the shell can vary from thin to fairly solid. The shell may be transparent and horn-colored, or colorless.
The number of whorls in the shell varies between two and eight. The shell can sometimes even assume a corkscrew or hornlike shape by loosening of the attachment of body whorl. The periostracum (outer layer of the shell) is usually thin, and is often colored. It can sometimes show hair-like projections.
The sinuous aperture is entire, not interrupted by a siphonal canal or other extensions. It is sometimes thickened. The protoconch is usually shaped like a dome, and usually shows a few spirals.
The corneous operculum is usually well-formed and shows only a few spirals.
The head, foot, mantle and visceral coil are colored pale gray to dark purple-black with melanin pigments. Subterranean species are often unpigmented.
The strong foot can be retracted into the shell. The mucous glands are situated at the anterior edge of the foot. There are no posterior mucous glands. The symmetrical cephalic tentacles are threadlike, with blunt or rounded tips. The eyes are located at the base of the tentacles.
The ctenidium (a comblike respiratory apparatus) goes along most of the length of the pallial cavity. This respiratory gill consists of 10 to 200 triangular filaments. The osphradium, the olfactory organ linked with the respiration organ, is usually relatively small.
The taenioglossate radula consists of more than fifty rows of teeth. The central tooth is trapezoidal. The lateral teeth have few to numerous cusps. The marginal teeth are usually with numerous cusps.
The species usually have both male and female individuals, but very rarely reproduction may be parthenogenic, caused by internal fertilization. The females lay eggs in single capsules on the leaves or stems of water plants. But sometimes they produce eggs that are hatched within the pallial gonoduct of the body, and in these cases the young are born alive. Species that inhabit estuaries sometimes produce veliger larvae.
The fossil record of this family extends back to the Early Carboniferous.
Ecology
Habitat
Most species of this family live in freshwater (lakes, ponds, rivers, streams), but some are found in brackish water or at the borders between freshwater and brackish water. A few occur in marine environments on sandy or muddy bottoms between algae and sea grass.
Feeding habits
These small snails feed on algae, diatoms and detritus.
Taxonomy
This is the largest family within the superfamily Truncatelloidea. At one time or another some 400 genera have been assigned to this family, and probably more than 1,000 species. The Hydrobiidae family is the most widespread and diverse family of freshwater molluscs in the world, occupying a range of habitats from streams and estuarine creeks to alpine bogs.
This family was originally named by Troschel in 1857, as the group Hydrobiae. Troschel was not certain of their rank, and he placed them in the Taenioglossata: Ctenobranchiata between the Lithoglyphi and Ancyloti. Over the years there have been numerous attempts to give an adequate and more finely divided classification. Thiele (1925, 1929 and 1931) set up the most comprehensive classification, with a review of the family at generic level.
Notable works about taxonomy of Hydrobiidae includes works by Radoman, for example Radoman (1983).
The classification, as specified by Kabat and Hershler (1993), does not form a monophyletic group, and was in need of revision.
A study by Wilke et al. (2001) using molecular data from COI (Cytochrome c oxidase subunit I) and 18S genes has resulted in a new tentative set of subfamilies: Hydrobiinae, Pseudamnicolinae, Nymphophilinae, Islamiinae and Horatiinae.
2005 taxonomy
The following subfamilies are recognized in the gastropod taxonomy of Bouchet & Rocroi from 2005:
Hydrobiinae Stimpson, 1865 – synonyms: Paludestrinidae Newton, 1891; Pyrgorientaliinae Radoman, 1977; Pseudocaspiidae Sitnikova & Starobogatov, 1983
Belgrandiinae de Stefani, 1877 – synonyms: Horatiini D. W. Taylor, 1966; Sadlerianinae Radoman, 1973; Pseudohoratiinae Radoman, 1973; Orientaliidae Radoman, 1973 (inv.); Lithoglyphulidae Radoman, 1973; Orientalinidae Radoman, 1978 (inv.); Belgrandiellinae Radoman, 1983; Dabrianidae Starobogatov, 1983; Istrianidae Starobogatov, 1983; Kireliinae Starobogatov, 1983; lanzaiidae Starobogatov, 1983; Tanousiidae Starobogatov, 1983; Bucharamnicolinae Izzatulaev, Sitnikova & Starobogatov, 1985; Martensamnicolinae Izzatulaev, Sitnikova & Starobogatov, 1985; Turkmenamnicolinae Izzatulaev, Sitnikova & Starobogatov, 1985
Clenchiellinae D. W. Taylor, 1966
Islamiinae Radoman, 1973
Nymphophilinae D. W. Taylor, 1966
Pseudamnicolinae Radoman, 1977
Pyrgulinae Brusina, 1882 (1869) – synonyms: Caspiidae B. Dybowski, 1913; Microliopalaeinae B. Dybowski & Grochmalicki, 1914; Micromelaniidae B. Dybowski & Grochmalicki, 1914; Turricaspiinae B. Dybowski & Grochmalicki, 1915; Liosarmatinae B. Dybowski & Grochmalicki, 1920; Chilopyrgulinae Radoman, 1973; Micropyrgulidae Radoman, 1973; Falsipyrgulinae Radoman, 1983; Ohridopyrgulinae Radoman, 1983; Prosostheniinae Pana, 1989
Tateinae Thiele, 1925 – synonyms: Potamopyrgidae F. C. Baker, 1928; Hemistomiinae Thiele, 1929
The Amnicolidae and Cochliopidae are considered as distinct families according to the taxonomy of Bouchet & Rocroi (2005).
Genera
Belgrandiellinae Radoman, 1983
Arganiella Giusti & Pezzoli, 1980
Balkanica Georgiev, 2011
Balkanospeum Georgiev, 2012
Belgrandiella A. J. Wagner, 1928
Boleana Radoman, 1975
Bythiospeum Bourguignat, 1882
Cavernisa Radoman, 1978
Cilgia Schütt, 1968
Costellina Kuščer, 1933
Devetakia Georgiev & Glöer, 2011
Devetakiola Georgiev, 2017
Graziana Radoman, 1975
Heraultiella Bodon, Manganelli & Giusti, 2002
Insignia Angelov, 1972
Istriana Velkovrh, 1971
Iverakia Glöer & Pešić, 2014
Kerkia Radoman, 1978
Kolevia Georgiev & Glöer, 2015
Lanzaia Brusina, 1906
Lanzaiopsis Bole, 1989
Meyrargueria Girardi, 2009
Microstygia Georgiev & Glöer, 2015
Palacanthilhiopsis Bernasconi, 1988
Phreatica Velkovrh, 1970
Plagigeyeria Tomlin, 1930
Pontobelgrandiella Radoman, 1978
Sarajana Radoman, 1975
Saxurinator Schütt, 1960
Stoyanovia Georgiev, 2017
Zeteana Glöer & Pešić, 2014
Belgrandiinae de Stefani, 1877
Agrafia Szarowska & Falniowski, 2011
Antibaria Radoman, 1983
Belchatovia Kadolsky & Piechocki, 2000
Belgrandia Bourguignat, 1870
Bracenica Radoman, 1973
Cyclothyrella Neubauer, Mandic, Harzhauser & Hrvatović, 2013
Dalmatella Velkovrh, 1970
Dalmatinella Radoman, 1973
Daphniola Radoman, 1973
Gloeria Georgiev, Dedov & Cheshmedjiev, 2012
Gocea Hadžišče, 1956
Graecoanatolica Radoman, 1973
Graecorientalia Radoman, 1983
Grossuana Radoman, 1983
Guadiella Boeters, 2003
Hadziella Kuščer, 1932
Hauffenia Pollonera, 1898
Isimerope Radea & Parmakelis, 2013
Karucia Glöer & Pešić, 2013
Litthabitella Boeters, 1970
Lyhnidia Radoman, 1962
Malaprespia Radoman, 1973
Martinietta Schlickum, 1974
Microprososthenia Kadolsky & Piechocki, 2000
Montenegrospeum Pešić & Glöer, 2013
Myrtoessa Radea, 2016
Narentiana Radoman, 1973
Ohridohauffenia Hadžišče, 1959
Ohridohoratia Hadžišče, 1959
Ohrigocea Hadžišče, 1959
Plesiella Boeters, 2003
Prespiana Radoman, 1973
Prespolitorea Radoman, 1983
Pseudavenionia Bodon & Giusti, 1982
Pseudohoratia Radoman, 1967
Pseudoislamia Radoman, 1979
Strugia Radoman, 1973
Sumia Glöer & Mrkvicka, 2015
Tarraconia Ramos & Arconada, 2000
Terranigra Radoman, 1978
Trichonia Schütt, 1980
Turcorientalia Radoman, 1973
Zaumia Radoman, 1983
Caspiinae B. Dybowski, 1913
Caspia Clessin & W. Dybowski, 1887
Horatiinae D.W. Taylor, 1966
Anagastina Radoman, 1978
Graecoarganiella Falniowski & Szarowska, 2011
Horatia Bourguignat, 1887
Pezzolia Bodon & Giusti, 1986
Radomaniola Szarowska, 2007
Sadleriana Clessin, 1890
Sardohoratia Manganelli, Bodon, Cianfanelli, Talenti & Giusti, 1998
Tanousia Servain, 1881
Vinodolia Radoman, 1973
Hydrobiinae Stimpson, 1865
Adriohydrobia Radoman, 1977
Ecrobia Stimpson, 1865
Hydrobia W. Hartmann, 1821
Peringia Paladilhe, 1874
Romania Cossmann, 1913
Salenthydrobia Wilke, 2003
Nymphophilinae
Birgella Baker, 1926
Incertae sedis
Anatolidamnicola Şahin, Koca & Yildirim, 2012
Andrusovia Brusina in Westerlund, 1902
Antillobia Altaba, 1993
Arabiella Kadolsky, Harzhauser & Neubauer in Harzhauser et al., 2016
Austropyrgus Cotton, 1942
Baglivia Brusina, 1892
Bania Brusina, 1896
Beogradica Pavlović, 1927
Brasovia Neubauer, Kroh, Harzhauser, Georgopoulou & Mandic, 2015
Bullaregia Khalloufi, Béjaoui & Delicado, 2017
Caspiohydrobia Starobogatov, 1970
Chirgisia Glöer, Boeters & Pešić, 2014
Coelacanthia Andrusov, 1890
Ctyrokya Schlickum, 1965
Fonscochlea Ponder, Hershler & Jenkins, 1989
Goniochilus Sandberger, 1875
Gyromelania Wenz, 1939
Heterocyclus Crosse, 1872
Rifia Ghamizi, 2020
Illyricella Neubauer, Mandic & Harzhauser, 2016
Intermaria Delicado, Pešić & Glöer, 2016
Iraklimelania Willmann, 1981
Jekeliella Bandel, 2010
Kadolskya Neubauer & Harzhauser, 2016
Kaskakia Glöer & Pešić, 2012
Kerchia Bandel, 2010
Lisinskia Brusina, 1897
Littoridinops Pilsbry, 1952
Lutetiella Kadolsky, 2015
Microbeliscus Sandberger, 1875
Micromelania Brusina, 1874
Mikrogoniochilus Willmann, 1981
Motsametia Vinarski, Palatov & Glöer, 2014
Muellerpalia Bandel, 2010
Navalis Quiñonero-Salgado & Rolán, 2017
Nematurella Sandberger, 1875
Neohoratia Schütt, 1961
Nicolaia Glöer, Bößneck, Walther & Neiber, 2016
Odontohydrobia Pavlović, 1927
Parhydrobia Cossmann & Dollfus, 1913
Persipyrgula Delicado, Pešić & Glöer, 2016
Pontohoratia Vinarski, Palatov & Glöer, 2014
Pontohydrobia Badzoshvili, 1979
Probythinella Thiele, 1928
Prososthenia Neumayr, 1869
Pseudamnicola Paulucci, 1878
Pseudocaspia Starobogatov, 1972
Pseudopaludinella Mabille, 1877
Pyrgulella Harzhauser, Neubauer & Kadolsky in Harzhauser et al., 2016
Rhodopyrgula Willmann, 1981
Robicia Brusina, 1897
Saccoia Brusina, 1893
Salakosia Willmann, 1981
Salalahia Kadolsky, Harzhauser & Neubauer in Harzhauser et al., 2016
Sarkhia Glöer & Pešić, 2012
Scalimelania Wenz, 1939
Sellia Raincourt, 1884
Shadinia Akramowski, 1976
Sivasi Şahin, Koca & Yildirim, 2012
Socenia Jekelius, 1944
Staja Brusina, 1897
Stalioa Brusina, 1870
Staliopsis Rzehak, 1893
Tefennia Schütt & Yildirim, 2003
Torosia Glöer & Georgiev, 2012
Tournouerina Schlickum, 1971
Vrazia Brusina, 1897
Wuconcha Kang, 1983
Xestopyrguloides Willmann, 1981
Islamiinae Radoman, 1973
Alzoniella Giusti & Bodon, 1984
Avenionia Nicolas, 1882
Boetersiella Arconada & Ramos, 2001
Chondrobasis Arconada & Ramos, 2001
Corbellaria Callot-Girardi & Boeters, 2012
Fissuria Boeters, 1981
Iberhoratia Arconada & Ramos, 2007
Islamia Radoman, 1973
Josefus Arconada & Ramos, 2006
Milesiana Arconada & Ramos, 2006
Pauluccinella Giusti & Pezzoli, 1990
Spathogyna Arconada & Ramos, 2002
Mercuriinae Boeters & Falkner, 2017
Mercuria Boeters, 1971
Pseudamnicolinae Radoman, 1977
Corrosella Boeters, 1970
Diegus Delicado, Machordom & Ramos, 2016
Falniowskia Bernasconi, 1991
Graecamnicola Willmann, 1981
Pyrgulinae E. von Martens, 1858
Chilopyrgula Brusina, 1896
Dianella Gude, 1913
Ginaia Brusina, 1896
Laevicaspia Dybowski & Grochmalicki, 1917
Maeotidia Andrusov, 1890
Marticia Brusina, 1897
Micropyrgula Polinski, 1929
Neofossarulus Poliński, 1929
Ohridopyrgula Radoman, 1983
Pseudodianella Neubauer, Mandic, Harzhauser & Hrvatović, 2013
Pyrgohydrobia Radoman, 1955
Pyrgula de Cristofori & Jan, 1832
Stankovicia Poliński, 1929
Trachyochridia Poliński, 1929
Turricaspia B. Dybowski & Grochmalicki, 1915
Xestopyrgula Poliński, 1929
Notes
References
External links
Taxa named by William Stimpson