Lanistes

Lanistes
Drawing of an apertural view of the shell of Lanistes ovum
Scientific classification
Kingdom:	Animalia
Phylum:	Mollusca
Class:	Gastropoda
(unranked):	clade Caenogastropoda informal group Architaenioglossa
Superfamily:	Ampullarioidea
Family:	Ampullariidae
Subfamily:	Ampullariinae
Tribe:	Ampullariini
Genus:	Lanistes Montfort, 1810
Type species
Lanistes carinatus (Olivier, 1804).
Diversity
21 extant species and at least 10 fossil species
Synonyms
Ampullaria (Lanistes) Lanistes (Meladomus) Swainson, 1840 Lanistes (Plesiolanistes) Berthold, 1991 Lanistes (Prolanistes) Schütt in Schütt & Besenecker, 1973 · accepted, alternate representation Leroya Grandidier, 1887 Meladomus Swainson, 1840 Meladomus (Bolteniana) Bourguignat, 1889 Meladomus (Lanistes) Meladomus (Libyciana) Bourguignat, 1889 Meladomus (Meladomus) Swainson, 1840 (formerly used as subgenus of Lanistes) Meladomus (Nyassana) Bourguignat, 1889 Meladomus (Olivaceana) Bourguignat, 1889 Meladomus (Purpuriana) Bourguignat, 1889

informal group Architaenioglossa

and at least 10 fossil species

Lanistes is a genus of freshwater snails which have a gill and an operculum, aquatic gastropod mollusks in the family Ampullariidae, the apple snails.

The distribution of the genus Lanistes includes Africa and Madagascar.

Lanistes has a unique anatomy among the Ampullariidae: it has a "hyperstrophic" sinistral shell. This means that the body of the snail is dextral (as in all other ampullariids), but the shell appears to be sinistral. However the sinistral appearance stems from the fact that the rotation of the shell as it grows is in an upward direction rather than the usual downward direction.

Three subgenera have been recognized, based on shell differences: Lanistes sensu stricto, Meladomus and Leroya. These subgenera are not used in recent works.

Extant species within the genus Lanistes include:

Fossil species within the genus Lanistes include:

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Wikipedia