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" (not to be confused with sea hares).

Tylomelania
Apertural view of a shell of Tylomelania neritiformis
Two Tylomelania sp.
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Mollusca
Class: Gastropoda
Subclass: Caenogastropoda
Family: Pachychilidae
Genus: Tylomelania
Sarasin & Sarasin, 1897[1]
Diversity[2][3][4]
46 described species

A sister group (the closest relative) of Tylomelania is genus Pseudopotamis (2 species living on the Torres Strait Islands).[5] Tylomelania and Pseudopotamis split in the Middle Miocene c. 19.5 Mya.[5]

Distribution

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Distribution map of Tylomelania (red area) cover the majority of Sulawesi. Grey area with dashed line is showing Wallacea.

Tylomelania are endemic to Sulawesi in Indonesia,[2] with the vast majority restricted to Lake Poso and the Malili Lake system (consisting of Matano and Towuti, and the smaller Lontoa (Wawantoa), Mahalona, Masapi).[6]

They most likely cannot inhabit altitudes above roughly 700 m (2,300 ft).[5]

Species

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Yellow Rabbit Snail tylomelania

There were known 34 described species in 2005.[2] Thomas von Rintelen with colleagues described 15 new species of Tylomelania in 2003–2008.

Tylomelania species diversification started in c. 5.4 Mya and was probably caused by the late Miocene and Pliocene orogeny.[5]

Species within the genus Tylomelania include:

Description

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In species within the genus, the albumen gland is very large.[2] The pallial oviduct evolved into a uterine brood, which releases shelled juvenile snails.[2] 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.[9] Comparison of apertural views of shells of twenty Tylomelania species are below, though are not of proper scale:

 
Tylomelania abendanoni
 
Tylomelania baskasti
 
Tylomelania carota
 
Tylomelania celebicola
 
Tylomelania centaurus
 
Tylomelania hannelorae
 
Tylomelania helmuti
 
Tylomelania lalemae
 
Tylomelania mahalonensis
 
Tylomelania masapensis
 
Tylomelania patriarchalis
 
Tylomelania perfecta
 
Tylomelania sarasinorum
 
Tylomelania sinabartfeldi
 
Tylomelania tominangensis
 
Tylomelania toradjarum
 
Tylomelania towutensis
 
Tylomelania towutica
 
Tylomelania wallacei
 
Tylomelania zeamais

Ecology

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Species in the genus Tylomelania are ovoviviparous.[2] Newly hatched snails of some species of Tylomelania measure nearly 2 cm (0.79 in) and are the largest newly hatched viviparous gastropods.[2]

References

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  1. ^ Sarasin P. & Sarasin F. (1897). "Über die Molluskenfauna der großen Süßwasser-Seen von Central-Celebes". Zoologischer Anzeiger 539/540: 308-320. page 317.
  2. ^ a b c d e f g h i j k l m n o p q r s t u v w x y z aa ab ac ad ae af ag ah ai aj ak al am von Rintelen T. & Glaubrecht M. (2005). "Anatomy of an adaptive radiation: a unique reproductive strategy in the endemic freshwater gastropod Tylomelania (Cerithioidea: Pachychilidae) on Sulawesi, Indonesia and its biogeographical implications." Biological Journal of the Linnean Society 85: 513–542. doi:10.1111/j.1095-8312.2005.00515.x.
  3. ^ a b c d e f g h i j k l von Rintelen, Bouchet P. & Glaubrecht M. (2007). "Ancient lakes as hotspots of diversity: a morphological review of an endemic species flock of Tylomelania (Gastropoda: Cerithioidea: Pachychilidae) in the Malili lake system on Sulawesi, Indonesia". Hydrobiologia 592:11–94. doi:10.1007/s10750-007-0765-8.
  4. ^ a b c d von Rintelen T. & Glaubrecht M. (2008). "Three new species of the freshwater snail genus Tylomelania (Caenogastropoda: Pachychilidae) from the Malili lake system, Sulawesi, Indonesia". Zootaxa 1852: 37–49. PDF.
  5. ^ a b c d von Rintelen T., Stelbrink B. Marwoto R. M. & Glaubrecht M. (2014). "A Snail Perspective on the Biogeography of Sulawesi, Indonesia: Origin and Intra-Island Dispersal of the Viviparous Freshwater Gastropod Tylomelania". PLoS ONE 9(6): e98917. doi:10.1371/journal.pone.0098917.
  6. ^ von Rintelen T., von Rintelen K. & Glaubrecht M. (2010). "The species flock of the viviparous freshwater gastropod Tylomelania (Mollusca: Cerithioidea: Pachychilidae) in the ancient lakes of Sulawesi, Indonesia: the role of geography, trophic morphology and colour as driving forces in adaptive radiation." pp. 485–512 in: Glaubrecht, M. & Schneider H. eds. (2010). Evolution in Action: Adaptive Radiations and the Origins of Biodiversity. Springer Verlag, Heidelberg, Germany.
  7. ^ a b c von Rintelen T. & Glaubrecht M. (2003). "New discoveries in old lakes: three new species of Tylomelania Sarasin & Sarasin, 1897 (Gastropoda: Cerithioidea: Pachychilidae) from the Malili lake system on Sulawesi, Indonesia". Journal of Molluscan Studies 69(1): 3–17. doi:10.1093/mollus/69.1.3
  8. ^ [1]
  9. ^ Elle Riley, May 9, 2023. "Rabbit Snail ‘Tylomelania’: A Complete Care Guide" https://fishhq.co/rabbit-snail/
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