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Pernastela Charon
''Pernastela charon'', also known as the lowland forest pinhead snail, is a species of land snail that is endemic to Australia's Lord Howe Island in the Tasman Sea. Description The trochoidal shell of the mature snail is 2.1–2.5 mm in height, with a diameter of 3.2–3.5 mm, and a raised spire. It is cream to pale golden-brown in colour. The whorls are rounded and flattened below an angular periphery, with moderately spaced radial ribs. It has a roundedly lunate aperture, flattened on the upper side by a reflected lip, and a moderately wide umbilicus. Distribution and habitat The snail is commonest in the settlement area of the island's lowlands, inhabiting plant litter in mixed forest. References * charon In Greek mythology, Charon or Kharon (; grc, Χάρων) is a psychopomp, the ferryman of Hades, the Greek underworld. He carries the souls of those who have been given funeral rites across the rivers Acheron and Styx, which separate the wo ... ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tom Iredale
Tom Iredale (24 March 1880 – 12 April 1972) was an English-born ornithologist and malacologist who had a long association with Australia, where he lived for most of his life. He was an Autodidacticism, autodidact who never went to university and lacked formal training. This was reflected in his later work; he never revised his manuscripts and never used a typewriter. Early life Iredale was born at Stainburn, Workington in Cumberland, England. He was apprenticed to a pharmacist from 1899 to 1901, and used to go bird watching and egg collecting in the Lake District with fellow chemist William Carruthers Lawrie. New Zealand Iredale emigrated to New Zealand following medical advice, as he had health issues. He may possibly have had tuberculosis. According to a letter to Will Lawrie dated 25 January 1902, he arrived in Wellington, New Zealand in December 1901, and travelled at once on to Lyttelton, New Zealand, Lyttelton and Christchurch. On his second day in Christchurch, he dis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Land Snail
A land snail is any of the numerous species of snail that live on land, as opposed to the sea snails and freshwater snails. ''Land snail'' is the common name for terrestrial gastropod mollusks that have shells (those without shells are known as slugs). However, it is not always easy to say which species are terrestrial, because some are more or less amphibious between land and fresh water, and others are relatively amphibious between land and salt water. Land snails are a polyphyletic group comprising at least ten independent evolutionary transitions to terrestrial life (the last common ancestor of all gastropods was marine). The majority of land snails are pulmonates that have a lung and breathe air. Most of the non-pulmonate land snails belong to lineages in the Caenogastropoda, and tend to have a gill and an operculum. The largest clade of land snails is the Cyclophoroidea, with more than 7,000 species. Many of these operculate land snails live in habitats or microhabitats ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endemism
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, the Cape sugarbird is found exclusively in southwestern South Africa and is therefore said to be ''endemic'' to that particular part of the world. An endemic species can be also be referred to as an ''endemism'' or in scientific literature as an ''endemite''. For example '' Cytisus aeolicus'' is an endemite of the Italian flora. '' Adzharia renschi'' was once believed to be an endemite of the Caucasus, but it was later discovered to be a non-indigenous species from South America belonging to a different genus. The extreme opposite of an endemic species is one with a cosmopolitan distribution, having a global or widespread range. A rare alternative term for a species that is endemic is "precinctive", which applies to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australia
Australia, officially the Commonwealth of Australia, is a Sovereign state, sovereign country comprising the mainland of the Australia (continent), Australian continent, the island of Tasmania, and numerous List of islands of Australia, smaller islands. With an area of , Australia is the largest country by area in Oceania and the world's List of countries and dependencies by area, sixth-largest country. Australia is the oldest, flattest, and driest inhabited continent, with the least fertile soils. It is a Megadiverse countries, megadiverse country, and its size gives it a wide variety of landscapes and climates, with Deserts of Australia, deserts in the centre, tropical Forests of Australia, rainforests in the north-east, and List of mountains in Australia, mountain ranges in the south-east. The ancestors of Aboriginal Australians began arriving from south east Asia approximately Early human migrations#Nearby Oceania, 65,000 years ago, during the Last Glacial Period, last i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lord Howe Island
Lord Howe Island (; formerly Lord Howe's Island) is an irregularly crescent-shaped volcanic remnant in the Tasman Sea between Australia and New Zealand, part of the Australian state of New South Wales. It lies directly east of mainland Port Macquarie, northeast of Sydney, and about southwest of Norfolk Island. It is about long and between wide with an area of , though just of that comprise the low-lying developed part of the island. Along the west coast is a sandy semi-enclosed sheltered coral reef lagoon. Most of the population lives in the north, while the south is dominated by forested hills rising to the highest point on the island, Mount Gower (). The Lord Howe Island Group comprises 28 islands, islets, and rocks. Apart from Lord Howe Island itself, the most notable of these is the volcanic and uninhabited Ball's Pyramid about to the southeast of Howe. To the north lies a cluster of seven small uninhabited islands called the Admiralty Group. The first repo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tasman Sea
The Tasman Sea (Māori: ''Te Tai-o-Rēhua'', ) is a marginal sea of the South Pacific Ocean, situated between Australia and New Zealand. It measures about across and about from north to south. The sea was named after the Dutch explorer Abel Janszoon Tasman, who in 1642 was the first known person to cross it. British explorer Lieutenant James Cook later extensively navigated the Tasman Sea in the 1770s during his three voyages of exploration. The Tasman Sea is informally referred to in both Australian and New Zealand English as the Ditch; for example, "crossing the Ditch" means travelling to Australia from New Zealand, or vice versa. The diminutive term "the Ditch" used for the Tasman Sea is comparable to referring to the North Atlantic Ocean as "the Pond". Climate The south of the sea is passed over by depressions going from west to east. The northern limit of these westerly winds is near to 40°S. During the southern winter, from April to October, the northern branch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Umbilicus (mollusc)
The umbilicus of a shell is the axially aligned, hollow cone-shaped space within the whorls of a coiled mollusc shell. The term umbilicus is often used in descriptions of gastropod shells, i.e. it is a feature present on the ventral (or under) side of many (but not all) snail shells, including some species of sea snails, land snails, and freshwater snails. The word is also applied to the depressed central area on the planispiral coiled shells of ''Nautilus'' species and fossil ammonites. (These are not gastropods, but shelled cephalopods.) In gastropods The spirally coiled whorls of gastropod shells frequently connect to each other by their inner sides, during the natural course of its formation. This results in a more or less solid central axial pillar, known as the columella. The more intimate the contact between the concave side of the whorls is, the more solid the columella becomes. On the other hand, if this connection is less intense, a hollow space inside the whorls may re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plant Litter
Plant litter (also leaf litter, tree litter, soil litter, litterfall or duff) is dead plant material (such as leaves, bark, needles, twigs, and cladodes) that have fallen to the ground. This detritus or dead organic material and its constituent nutrients are added to the top layer of soil, commonly known as the litter layer or O horizon ("O" for "organic"). Litter is an important factor in ecosystem dynamics, as it is indicative of ecological productivity and may be useful in predicting regional nutrient cycling and soil fertility. Characteristics and variability Litterfall is characterized as fresh, undecomposed, and easily recognizable (by species and type) plant debris. This can be anything from leaves, cones, needles, twigs, bark, seeds/nuts, logs, or reproductive organs (e.g. the stamen of flowering plants). Items larger than 2 cm diameter are referred to as coarse litter, while anything smaller is referred to as fine litter or litter. The type of litterfall is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pernastela
''Pernastela'' is a genus of three pinhead or dot snail species that are endemic to Australia's Lord Howe Island in the Tasman Sea. Species * ''Pernastela charon'' Iredale, 1944 – lowland forest pinhead snail * ''Pernastela gnoma'' Iredale, 1944 – dwarf pinhead snail * ''Pernastela howensis ''Pernastela howensis'', also known as the Lord Howe pinhead snail, is a tiny species of land snail that is endemic to Australia's Lord Howe Island in the Tasman Sea. Description The trochoidal shell of the mature snail is 1.8–2.1 mm in ...'' Iredale, 1944 – Lord Howe pinhead snail References * Gastropod genera Taxa named by Tom Iredale Gastropods described in 1944 Gastropods of Lord Howe Island {{Punctidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastropods Of Lord Howe Island
The gastropods (), commonly known as snails and slugs, belong to a large taxonomic class of invertebrates within the phylum Mollusca called Gastropoda (). This class comprises snails and slugs from saltwater, from freshwater, and from land. There are many thousands of species of sea snails and slugs, as well as freshwater snails, freshwater limpets, and land snails and slugs. The class Gastropoda contains a vast total of named species, second only to the insects in overall number. The fossil history of this class goes back to the Late Cambrian. , 721 families of gastropods are known, of which 245 are extinct and appear only in the fossil record, while 476 are currently extant with or without a fossil record. Gastropoda (previously known as univalves and sometimes spelled "Gasteropoda") are a major part of the phylum Mollusca, and are the most highly diversified class in the phylum, with 65,000 to 80,000 living snail and slug species. The anatomy, behavior, feeding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Taxa Named By Tom Iredale
In biology, a taxon (back-formation from ''taxonomy''; plural taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and given a particular ranking, especially if and when it is accepted or becomes established. It is very common, however, for taxonomists to remain at odds over what belongs to a taxon and the criteria used for inclusion. If a taxon is given a formal scientific name, its use is then governed by one of the nomenclature codes specifying which scientific name is correct for a particular grouping. Initial attempts at classifying and ordering organisms (plants and animals) were set forth in Carl Linnaeus's system in ''Systema Naturae'', 10th edition (1758), as well as an unpublished work by Bernard and Antoine Laurent de Jussieu. The idea of a unit-based system of biological classification was first made widely available in 1805 in the intro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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