Pachychilidae , common name pachychilids , is a taxonomic family of freshwater snails , gastropod molluscs in the clade Sorbeoconcha.
Pachychilids are freshwater snails with a worldwide distribution in the tropics. Representatives are found in South and Central America , Africa, Madagascar , South and South-east Asia and tropical Australia (Queensland : Torres Strait Islands ).
Pachychilids have an operculum , which is concentric and multispiral.
All species in the family inhabit freshwater except Faunus ater brackish water snail found in estuaries and other coastal habitats. Pachychilids are either oviparous (lay eggs), ovoviviparous or viviparous (retain developing eggs and youngs in special incubatory structures).
Genera within the family Pachychilidae include:
† Bellatara Strand, 1928 - with only one species Bellatara janus (Mayer, 1870) Brotia Doryssa † Eginea Pacaud & Harzhauser, 2012 Faunus de Montfort, 1810 with the only species Faunus ater Linnaeus , 1758)Jagora † Jponsia Pacaud & Harzhauser, 2012 Madagasikara Melanatria Bowdich , 1822 auctt.† Nodifaunus Olsson, 1944 Pachychilus Paracrostoma Cossmann, 1900Potadoma Swainson, 1840† Pseudobellardia Cox, 1931 Pseudopotamis Sulcospira Adamietta Brandt, 1974† Tinnyea Hantken, 1887 Tylomelania † Wingeastonia K. Martin, 1906 Genera brought into synonymy Acrostoma Brot, 1871: synonym of Paracrostoma Cossmann, 1900Antimelania P. Fischer & Crosse , 1892: synonym of Brotia H. Adams, 1866Brotella Rovereto, 1899: synonym of Paracrostoma Cossmann, 1900Fauninae Cossmann, 1909 (subfamily) : synonym of Pachychilidae P. Fischer & Crosse, 1892 Melanatria Bowdich, 1822: synonym of Faunus Montfort, 1810Oxymelania Crosse & P. Fischer, 1892: synonym of Pachychilus Pirena Lamarck, 1822: synonym of Faunus Montfort, 1810Sphaeromelania Rovereto, 1899: synonym of Pachychilus I. Lea & H. C. Lea, 1851Wanga Chen, 1943: synonym of Brotia H. Adams, 1866A cladogram based on sequences of mitochondrial 16S ribosomal RNA sequences showing phylogenic relations of Pachychilidae:
