Tylomelania
Tylomelania is a genus of freshwater snails which have an operculum, aquatic gastropod mollusks in the family Pachychilidae. In the aquarium hobby, snails from this genus are commonly known as "rabbit snails".
A sister group of Tylomelania is genus Pseudopotamis. Tylomelania and Pseudopotamis split in the Middle Miocene.
Distribution
Tylomelania are endemic to Sulawesi in Indonesia, with the vast majority restricted to Lake Poso and the Malili Lake system.They most likely cannot inhabit altitudes above roughly.
Species
There were known 34 described species in 2005. Thomas von Rintelen with colleagues described 15 new species of Tylomelania in 2003–2008.Tylomelania species diversification started in and was probably caused by the late Miocene and Pliocene orogeny.
Species within the genus Tylomelania include:Tylomelania abendanoni Tylomelania amphiderita Tylomelania bakara Tylomelania baskasti Tylomelania carbo Tylomelania carota Tylomelania celebicola Tylomelania centaurus Tylomelania confusa Tylomelania connectens Tylomelania gemmifera Tylomelania hannelorae Tylomelania helmuti Tylomelania inconspicua Tylomelania insulaesacrae Tylomelania kristinae Tylomelania kruimeli Tylomelania kuli Tylomelania lalemae Tylomelania mahalonensis – synonym: Tylomelania mahalonica Tylomelania marwotoae Tylomelania masapensis Tylomelania matannensis Tylomelania molesta Tylomelania monacha Tylomelania neritiformis Tylomelania palicolarum Tylomelania patriarchalis Tylomelania perconica Tylomelania perfecta Tylomelania porcellanica Tylomelania robusta Tylomelania sarasinorum Tylomelania scalariopsis Tylomelania sinabartfeldi Tylomelania solitariaTylomelania tominangensis Tylomelania tomoriensis Tylomelania toradjarum Tylomelania towutensis Tylomelania towutica Tylomelania turriformis Tylomelania wallacei Tylomelania wesseli Tylomelania wolterecki
Description
In species within the genus, the albumen gland is very large. The pallial oviduct evolved into a uterine brood, which releases shelled juvenile snails. Compared to other aquatic snails, many species of Tylomelania are known to be the few groups of snails that are not hermaphroditic but rather dioecious.Comparison of apertural views of shells of twenty Tylomelania species are below, though are not of proper scale: