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Zyzzyxdonta
''Zyzzyxdonta alata'' is a species of air-breathing land snail, a terrestrial pulmonate gastropod mollusk in the family Endodontidae. This is the only species in the genus ''Zyzzyxdonta''. The genus was named ''Zyzzyxdonta'' because it has many features that are the opposite to the genus ''Aaadonta''. The name, given to the snail by malacologist Alan Solem, is the last word in many species dictionaries, just after ''Zyzzyx''; however, they both, in fact, precede ''Zyzzyzus''. They live in the Pacific islands of Palau and Fiji. Description The shell of ''Zyzzyxdonta alata'' has apical sculpture typical of the Endodontidae. The postnuclear whorls have widely spaced radial ribs which protrude into hollow, winglike structures at the carinated periphery. There are about 5 whorls that are rather loosely coiled. The apex is flat, but the spire is slightly elevated. The body whorl has a protruded, keeled periphery, not descending more rapidly, with a distinct subperipheral sulcus. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aaadonta
''Aaadonta'' is a genus of air-breathing land snails, terrestrial animal, terrestrial pulmonate gastropod mollusks in the family Endodontidae. Specimens from this genus are endemic to Palau. Species Species in the genus ''Aaadonta'' include: * ''Aaadonta angaurana'' Alan Solem, Solem, 1976 * ''Aaadonta constricta'' Carl Semper, Semper, 1874; Type species * ''Aaadonta fuscozonata'' (E.H. Beddome, 1889) * ''Aaadonta irregularis'' Semper, 1874 * ''Aaadonta kinlochi'' Solem, 1976 * ''Aaadonta pelewana'' Solem, 1976 The genus was given its unusual name by the biologist Alan Solem, who wanted it to appear first in any alphabetical list of endodontid genera. For animal genera, the first alphabetically listed name is ''Aaaaba'', which is a genus of beetles from Australia. The current conservation status, according to the IUCN Red List, varies depending on species, though they all fall into the larger category of being threatened. One cause of a low population stated by Solem could be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Endodontidae
Endodontidae is a taxonomic family of very small air-breathing land snails and slugs, terrestrial pulmonate gastropod molluscs in the superfamily Punctoidea. This family, which includes both snails and slugs, appears to have once been much more diverse, but has declined, and is now endangered due to human activity. Anatomy In this family, the number of haploid chromosomes lies between 26 and 35 (according to the values in this table).Barker G. M.: Gastropods on Land: ''Phylogeny, Diversity and Adaptive Morphology''. in Barker G. M. (ed.): The biology of terrestrial molluscs'. CABI Publishing, Oxon, UK, 2001, . 1-146, cited pages: 139 and 142. Distribution and conservation status This family is found only in the Pacific islands. The family is critically endangered and on the verge of extinction, mainly because of habitat loss due to human development. On American Samoa, some species are in decline due to predation by introduced fire ants. On Rurutu in French Polynesia the fam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Alan Solem
George Alan Solem (21 June 1931 – 26 March 1990),Coan E. V., Kabat A. R. & Petit R. E. (2009). ''2,400 years of malacology, 6th ed.'', February 15, 2009, 830 pp. + 32 pp. nnex of Collations American Malacological Society: http://www.malacological.org/publications/2400_malacology.html known professionally as Alan Solem, was an American malacologist, a biologist who studied mollusks. He was one of the most renowned land snail experts of his time and had earned a reputation for his comprehensive revisions of mainly terrestrial pulmonates. He worked on land snails from all regions of the world but became particularly known for his revisions of land snails from Australasia and various Pacific Islands. His 140 academic papers dealt with the snail phylogeny, feeding patterns and reproductive strategies. He named many taxa, amongst them about 350 species of Australian land snails, and several genera.Cameron, R. A. D., B. M. Pokryszko, and F. E. Wells. 2005. Alan Solem's work on the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palau
Palau, officially the Republic of Palau, is an island country in the Micronesia subregion of Oceania in the western Pacific Ocean. The Republic of Palau consists of approximately 340 islands and is the western part of the Caroline Islands, while the eastern and central parts make up the Federated States of Micronesia. It has a total area of , making it the sixteenth smallest country in the world. The most populous island is Koror, home to the country's most populous city of the same name. The capital, Ngerulmud, is located on the largest island of Babeldaob, in Melekeok State. Palau shares maritime boundaries with international waters to the north, the Federated States of Micronesia to the east, Indonesia to the south, and the Philippines to the northwest. The country was originally settled approximately 3,000 years BP by migrants from Maritime Southeast Asia. Palau was first drawn on a European map by the Bohemian missionary Paul Klein based on a description g ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aaaaba
''Aaaaba'' is a genus of beetles from the Buprestidae family. It inhabits locations along the east coast of Australia. It was described in 1864 by Achille Deyrolle as "''Alcinous''", a junior homonym of a genus of pycnogonids. In 2002, Charles Bellamy gave it the replacement name "''Aaaba''", but this proved to be another junior homonym, of a genus of sponges. In 2013, it was given a further replacement name, becoming ''Aaaaba''. There are two species within this genus: *'' Aaaaba nodosa'' ( Deyrolle, 1865) *'' Aaaaba fossicollis'' ( Kerremans, 1903) The genus name is feminine under ICZN Article 30.2.4 ("If no gender was specified or indicated, the name is to be treated as masculine, except that, if the name ends in the gender is feminine"). Distribution Species of this genus are found in New South Wales, Queensland and Victoria Victoria most commonly refers to: * Queen Victoria (1819–1901), Queen of the United Kingdom and Empress of India * Victoria (state), a state of A ... [...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 (mollusc), 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 (mollusc), aperture of the shell. These ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aperture (mollusc)
The aperture is an opening in certain kinds of mollusc shells: it is the main opening of the shell, where the head-foot part of the body of the animal emerges for locomotion, feeding, etc. The term ''aperture'' is used for the main opening in gastropod shells, scaphopod shells, and also for ''Nautilus'' and ammonite shells. The word is not used to describe bivalve shells, where a natural opening between the two shell valves in the closed position is usually called a ''gape (bivalve), gape''. Scaphopod shells are tubular, and thus they have two openings: a main anterior aperture and a smaller posterior aperture. As well as the aperture, some gastropod shells have additional openings in their shells for respiration; this is the case in some Fissurellidae (keyhole limpets) where the central smaller opening at the apex (mollusc), apex of the shell is called an orifice, and in the Haliotidae (abalone) where the row of respiratory openings in the shell are also called orifices. In ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Umbilicus (mollusk)
The umbilicus of a coiled mollusc shell is the axially aligned, hollow cone-shaped space within its whorls. 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 result, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Whorl
The body whorl is part of the morphology (biology), morphology of the gastropod shell, shell in those gastropod mollusks that possess a coiled shell. The term is also sometimes used in a similar way to describe the shell of a cephalopod mollusk. In gastropods In gastropods, the body whorl, or last whorl, is the most recently formed and largest Whorl (mollusc), whorl (or revolution) of a spiral or Helix, helical Gastropod shell, shell, terminating in the Aperture (mollusc), aperture. It is called the "body whorl" because most of the body of the soft parts of the animal fits into this whorl. The proportional size of the body whorl in gastropod shells differs greatly according to the actual shell morphology. For shells in which the rate of whorl expansion of each revolution around the axis is very high, the aperture and the body whorl are large, and the shell tends to be low Spire (mollusc), spired. The shell of the abalone is a good example of this kind of shell. The opposite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spire (mollusc)
A spire is a part of the coiled shell of molluscs. The spire consists of all of the whorls except for the body whorl. Each spire whorl represents a rotation of 360°. A spire is part of the shell of a snail, a gastropod mollusc, a gastropod shell, and also the whorls of the shell in ammonites, which are fossil shelled cephalopods. In textbook illustrations of gastropod shells, the tradition (with a few exceptions) is to show most shells with the spire uppermost on the page. The spire, when it is not damaged or eroded, includes the protoconch (also called the nuclear whorls or the larval shell), and most of the subsequent teleoconch whorls (also called the postnuclear whorls), which gradually increase in area as they are formed. Thus the spire in most gastropods is pointed, the tip being known as the " apex". The word "spire" is used, in an analogy to a church spire or rock spire, a high, thin, pinnacle. The "spire angle" is the angle, as seen from the apex, at which a s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apex (mollusc)
In anatomy, an apex (adjectival form: apical) is part of the mollusc shell, shell of a mollusk. The apex is the pointed tip (the oldest part) of the shell of a gastropod, scaphopod, or cephalopod. The apex is used in end-blown conch (instrument), conches. Gastropods The word "apex" is most often used to mean the tip of the spire (mollusc), spire of the shell of a gastropod. The apex is the first-formed, and therefore the oldest, part of the shell. To be more precise, the apex would usually be where the tip of the embryonic shell or protoconch is situated, if that is still present in the adult shell (often it is lost or eroded away). Coiled gastropod shells The phrase apical whorls, or protoconch, means the whorls that constitute the embryonic shell at the apex of the shell, especially when this is clearly distinguishable from the later whorls of the shell, otherwise known as the teleoconch. Comparison of the apical part and the whole shell of ''Otukaia kiheiziebisu'': File:Cal ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Whorl (mollusc)
A whorl is a single, complete 360° revolution or turn in the spiral or whorled 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 Cone (geometry), conical tube, the growth of which is coiled into an overall Helix, 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 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
