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Tylomelania Patriarchalis
''Tylomelania patriarchalis'' is a species of freshwater snail with an operculum, an aquatic gastropod mollusk in the family Pachychilidae. Distribution This species occurs in Malili lakes, Sulawesi, Indonesia. It occur in the single lake and the type locality is the lake Matano. Description The shell has 6-9 whorls A whorl ( or ) is an individual circle, oval, volution or equivalent in a whorled pattern, which consists of a spiral or multiple concentric objects (including circles, ovals and arcs). Whorls in nature File:Photograph and axial plane floral d .... The width of the shell is 26 mm. The height of the shell is 82 mm. The width of the aperture is 14 mm. The height of the aperture is 22 mm. There are 6-7 concentric lines on the operculum. References External links * von Rintelen T. & Glaubrecht M. (2005). "Anatomy of an adaptive radiation: a unique reproductive strategy in the endemic freshwater gastropod ''Tylomelania'' (Ce ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastropod Shell
The gastropod shell is part of the body of a Gastropoda, gastropod or snail, a kind of mollusc. The shell is an exoskeleton, which protects from predators, mechanical damage, and dehydration, but also serves for muscle attachment and calcium storage. Some gastropods appear shell-less (slugs) but may have a remnant within the mantle, or in some cases the shell is reduced such that the body cannot be retracted within it (semi-slug). Some snails also possess an operculum that seals the opening of the shell, known as the Aperture (mollusc), aperture, which provides further protection. The study of mollusc shells is known as conchology. The biological study of gastropods, and other molluscs in general, is malacology. Shell morphology terms vary by species group. Shell layers The gastropod shell has three major layers secreted by the Mantle (mollusc), mantle. The calcareous central layer, tracum, is typically made of calcium carbonate precipitated into an organic matrix known as c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachychilidae
Pachychilidae, common name pachychilids, is a taxonomic family of freshwater snails, gastropod molluscs in the clade Sorbeoconcha.Gofas, S. (2014). Pachychilidae. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=411651 on 2014-11-20 Distribution 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). Description Pachychilids have an operculum, which is concentric and multispiral. Ecology All species in the family inhabit freshwater except '' Faunus ater'', which is a 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). Notes on the taxonomy The name is derived from a co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biological Journal Of The Linnean Society
The ''Biological Journal of the Linnean Society'' is a direct descendant of the oldest biological journal in the world, the ''Transactions of the Linnean Society''. It succeeded the earlier title in 1969. The journal specializes in evolution, and encompasses work across all taxonomic groups in all five kingdoms of living organisms. It includes all methods, whole-organism or molecular, practical or theoretical. The journal is published by the Linnean Society of London The Linnean Society of London is a learned society dedicated to the study and dissemination of information concerning natural history, evolution, and taxonomy. It possesses several important biological specimen, manuscript and literature colle .... References External links * Linnean Society of London Biology journals English-language journals Publications with year of establishment missing {{biology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operculum (gastropod)
The operculum (; ) is a corneous or calcareous anatomical structure like a trapdoor that exists in many (but not all) groups of sea snails and freshwater snails, and also in a few groups of land snails; the structure is found in some marine and freshwater gastropods, and in a minority of terrestrial gastropods, including the families Helicinidae, Cyclophoridae, Aciculidae, Maizaniidae, Pomatiidae, etc. The operculum is attached to the upper surface of the foot and in its most complete state, it serves as a sort of "trapdoor" to close the aperture of the shell when the soft parts of the animal are retracted. The shape of the operculum varies greatly from one family of gastropods to another. It is fairly often circular, or more or less oval in shape. In species where the operculum fits snugly, its outline corresponds exactly to the shape of the aperture of the shell and it serves to seal the entrance of the shell. Many families have opercula that are reduced in size, and which a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral growth of a mollusc shell. A spiral configuration of the shell is found in numerous gastropods, but it is also found in shelled cephalopods including ''Nautilus'', ''Spirula'' and the large extinct subclass of cephalopods known as the ammonites. A spiral shell can be visualized as consisting of a long conical tube, the growth of which is coiled into an overall helical or planispiral shape, for reasons of both strength and compactness. The number of whorls which exist in an adult shell of a particular species depends on mathematical factors in the geometric growth, as described in D'Arcy Wentworth Thompson's classic 1917 book ''On Growth and Form'', and by David Raup. The main factor is how rapidly the conical tube expands (or flares-out) over time. When the rate of expansion is low, such that each subsequent whorl is not that much wider than the previous one, then the adult shell has numerous whorls. When the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tylomelania Patriarchalis Shell
''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). A sister group (the closest relative) of ''Tylomelania'' is genus ''Pseudopotamis'' (2 species living on the Torres Strait Islands).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. . ''Tylomelania'' and ''Pseudopotamis'' split in the Middle Miocene c. 19.5 Mya. Distribution These freshwater snails are endemic to Sulawesi in Indonesia, 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).von Rintelen T., von Rintele ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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