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Monodonta Australis
''Monodonta australis'', common name the toothed topshell, is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails. Description The size of the shell varies between 12 mm and 35 mm. The shell is similar to ''Monodonta labio'', but with rounder whorls, more marked sutures and with lower lirae. It is not granulose. It is tessellated with black and grayish or greenish. The penultimate whorl is subangulate by the prominence of its central rib. The columella is much less strongly dentate than in ''Monodonta labio'', and the notch or canal below it shallow. The basal plicae are less developed than in ''Monodontia labio''. Distribution This marine species occurs off South Africa and in the Indian Ocean off Madagascar, Aldabra and the Mascarene Basin; also off Japan Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monodonta Australis B
''Monodonta'' is a genus of sea snails, marine gastropod mollusks in the family Trochidae, the top snails. The genus ''Monodonta'' was first separated from the Linnaean genus '' Trochus'' by Lamarck in 1801 with ''Trochus labio'' Linnaeus, 1758 given as the type species. ''Labio'' is a junior homonym of ''Labio'' Oken, 1815, itself a synonym of ''Monodonta'' Lamarck, 1799 Description The very heavy, thick, solid shell has a turbinate-conic shape. The shell is smooth or spirally ridged. The outer lip is plicate within. The short, porcellanous columella is strong, cylindrical, bulging or more or less toothed near or at the base. Between this tooth and the basal margin there is a square notch or channel. The aperture is as high as wide. Distribution The species of this marine genus occurs over a wide area: Central and East Indian Ocean, Indo-China, Indo-Malaysian Oceania, the Philippines, Japan and Australia (Northern Territory, Queensland, Western Australia). Species ... [...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] |
Japan
Japan ( ja, 日本, or , and formally , ''Nihonkoku'') is an island country in East Asia. It is situated in the northwest Pacific Ocean, and is bordered on the west by the Sea of Japan, while extending from the Sea of Okhotsk in the north toward the East China Sea, Philippine Sea, and Taiwan in the south. Japan is a part of the Ring of Fire, and spans Japanese archipelago, an archipelago of List of islands of Japan, 6852 islands covering ; the five main islands are Hokkaido, Honshu (the "mainland"), Shikoku, Kyushu, and Okinawa Island, Okinawa. Tokyo is the Capital of Japan, nation's capital and largest city, followed by Yokohama, Osaka, Nagoya, Sapporo, Fukuoka, Kobe, and Kyoto. Japan is the List of countries and dependencies by population, eleventh most populous country in the world, as well as one of the List of countries and dependencies by population density, most densely populated and Urbanization by country, urbanized. About three-fourths of Geography of Japan, the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mascarene
The Mascarene Islands (, ) or Mascarenes or Mascarenhas Archipelago is a group of islands in the Indian Ocean east of Madagascar consisting of the islands belonging to the Republic of Mauritius as well as the French department of Réunion. Their name derives from the Portuguese navigator Pedro Mascarenhas, who first visited them in April 1512. The islands share a common geologic origin in the volcanism of the Réunion hotspot beneath the Mascarene Plateau and form a distinct ecoregion with a unique flora and fauna. Geography The archipelago comprises three large islands, Mauritius, Réunion, and Rodrigues, plus a number of volcanic remnants in the tropics of the southwestern Indian Ocean, generally between 700 and 1500 kilometres east of Madagascar. The terrain includes a variety of reefs, atolls, and small islands. They present various topographical and edaphic regions. On the largest islands these gave rise to unusual biodiversity. The climate is oceanic and tropical. Mauriti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aldabra
Aldabra is the world's second-largest coral atoll, lying south-east of the continent of Africa. It is part of the Aldabra Group of islands in the Indian Ocean that are part of the Outer Islands of the Seychelles, with a distance of 1,120 km (700 mi) southwest of the capital, Victoria on Mahé Island. History The name Aldabra, originally Al-Hadra or Al-Khadra (with several variants), was given by Arab seafarers for "the atoll’s harsh, sun-baked environment"; this name was included in the Portuguese maps of the 16th century. The islands were already known to the Persians and Arabs, from whom they got their name. They had named the Indian Ocean as Bahr-el zanj. It was visited by Portuguese navigators in 1511. In the middle of the 18th century, the atoll became a dependency of the French colony of Réunion, from where expeditions were made for the capture of the Aldabra giant tortoises. As there are no surface freshwater sources on Aldabra, the interests of the explor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Madagascar
Madagascar (; mg, Madagasikara, ), officially the Republic of Madagascar ( mg, Repoblikan'i Madagasikara, links=no, ; french: République de Madagascar), is an island country in the Indian Ocean, approximately off the coast of East Africa across the Mozambique Channel. At Madagascar is the world's List of island countries, second-largest island country, after Indonesia. The nation is home to around 30 million inhabitants and consists of the island of Geography of Madagascar, Madagascar (the List of islands by area, fourth-largest island in the world), along with numerous smaller peripheral islands. Following the prehistoric breakup of the supercontinent Gondwana, Madagascar split from the Indian subcontinent around 90 million years ago, allowing native plants and animals to evolve in relative isolation. Consequently, Madagascar is a biodiversity hotspot; over 90% of wildlife of Madagascar, its wildlife is endemic. Human settlement of Madagascar occurred during or befo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
South Africa
South Africa, officially the Republic of South Africa (RSA), is the southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countries of Namibia, Botswana, and Zimbabwe; and to the east and northeast by Mozambique and Eswatini. It also completely enclaves the country Lesotho. It is the southernmost country on the mainland of the Old World, and the second-most populous country located entirely south of the equator, after Tanzania. South Africa is a biodiversity hotspot, with unique biomes, plant and animal life. With over 60 million people, the country is the world's 24th-most populous nation and covers an area of . South Africa has three capital cities, with the executive, judicial and legislative branches of government based in Pretoria, Bloemfontein, and Cape Town respectively. The largest city is Johannesburg. About 80% of the population are Black South Afri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Columella (gastropod)
The columella (meaning "little column") or (in older texts) pillar is a central anatomical feature of a coiled snail shell, a gastropod shell. The columella is often only clearly visible as a structure when the shell is broken, sliced in half vertically, or viewed as an X-ray image. The columella runs from the apex of the shell to the midpoint of the undersurface of the shell, or the tip of the siphonal canal in those shells which have a siphonal canal. If a snail shell is visualized as a cone of shelly material which is wrapped around a central axis, then the columella more or less coincides spatially with the central axis of the shell. In the case of shells that have an umbilicus, the columella is a hollow structure. The columella of some groups of gastropod shells can have a number of plications or folds (the columellar fold, plaits or plicae), which are usually visible when looking to the inner lip into the aperture of the shell. These folds can be wide or narrow, prominent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suture (anatomy)
In anatomy, a suture is a fairly rigid joint between two or more hard elements of an organism, with or without significant overlap of the elements. Sutures are found in the skeletons or exoskeletons of a wide range of animals, in both invertebrates and vertebrates. Sutures are found in animals with hard parts from the Cambrian period to the present day. Sutures were and are formed by several different methods, and they exist between hard parts that are made from several different materials. Vertebrate skeletons The skeletons of vertebrate animals (fish, amphibians, reptiles, birds, and mammals) are made of bone, in which the main rigid ingredient is calcium phosphate. Cranial sutures The skulls of most vertebrates consist of sets of bony plates held together by cranial sutures. These sutures are held together mainly by Sharpey's fibers which grow from each bone into the adjoining one. Sutures in the ankles of land vertebrates In the type of crurotarsal ankle which is found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monodonta Labio
''Monodonta labio'', common name the toothed top shell or the lipped periwinkle, is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails. Distribution This species occurs in the Indian Ocean off Madagascar and the Mascarene basin and in the Western Pacific and off the Philippines and commonly seen in Hong Kong near tide line. Description The length of the shell size varies between 15 mm and 45 mm. The shell is heavy and coarse with rough, grained surface with moderate sutures between rounded whorls. The body whorl is swollen and the penultimate whorl somewhat less. The shell shows a rounded keel (a spiral ridge marking a change of slope) and an umbilicus sealed with a callus. The apex is often worn away in adults. The columella has a prominent, blunt tooth. The inner edge of the outer lip shows a number of smaller knobs. The aperture has a nacreous interior. The color of the shell varies from a dark reddish brown to pale br ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monodonta Australis F
''Monodonta'' is a genus of sea snails, marine gastropod mollusks in the family Trochidae, the top snails. The genus ''Monodonta'' was first separated from the Linnaean genus '' Trochus'' by Lamarck in 1801 with ''Trochus labio'' Linnaeus, 1758 given as the type species. ''Labio'' is a junior homonym of ''Labio'' Oken, 1815, itself a synonym of ''Monodonta'' Lamarck, 1799 Description The very heavy, thick, solid shell has a turbinate-conic shape. The shell is smooth or spirally ridged. The outer lip is plicate within. The short, porcellanous columella is strong, cylindrical, bulging or more or less toothed near or at the base. Between this tooth and the basal margin there is a square notch or channel. The aperture is as high as wide. Distribution The species of this marine genus occurs over a wide area: Central and East Indian Ocean, Indo-China, Indo-Malaysian Oceania, the Philippines, Japan and Australia (Northern Territory, Queensland, Western Australia). Species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trochidae
The Trochidae, common name top-snails or top-shells, are a family of various sized sea snails, marine gastropod molluscs in the subclass Vetigastropoda. This family is commonly known as the top-snails because in many species the shell resembles a toy spinning top. Taxonomy The family Trochidae consists of the following subfamilies: * Alcyninae Williams, Donald, Spencer & Nakano, 2010 * Cantharidinae Gray, 1857 * Carinotrochinae S.-Q. Zhang, J. Zhang & S.-P. Zhang, 2020 * Chrysostomatinae Williams, Donald, Spencer & Nakano, 2010 * Fossarininae Bandel, 2009 * Halistylinae Keen, 1958 * Kaiparathininae B. A. Marshall, 1993 * Monodontinae Gray, 1857 * Stomatellinae Gray, 1840 * Trochinae Rafinesque, 1815 * Umboniinae H. Adams & A. Adams, 1854 (1840) Additionally, the following genera have not yet been placed in any subfamily: * '' Callumbonella'' Thiele, 1924 * †'' Coeloconulus'' Nützel, 2012 * '' Enida'' A. Adams, 1860 * †'' Eocalliostoma'' O. Haas, 1953 * †'' Fa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
