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Halistylus
''Halistylus'' is a genus of very small sea snails, marine gastropod mollusks in the family Trochidae, the top snails. Description The small, polychromatic shell has a cylindrical shape. It is holostomatous, i.e. the aperture is rounded or entire, uninterrupted by the siphonal canal, notch, or by any other extension. The operculum is multispiral and coriaceous. There is no spiral sculpture. Such a cylindrical shape is rather uncommon in the family 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 .... But the belonging of this genus to this family is certified by the shell structure, the pearly aperture and anatomical features. This genus was previously considered a subgenus of the genus '' Cantharidus'' Montfort Species Species within the genus ''Halistylus'' include: * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halistylus Pupoideus
''Halistylus pupoideus'' is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.Bouchet, P.; Rosenberg, G. (2012). ''Halistylus pupoideus'' (Carpenter, 1864). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=528714 on 2012-11-23 This species has been misspelled ''Halistylus pupoides'' in the 19th century literature. Description The shell grows to a length of 6 mm. This species occurs invariably with '' Caecum crebricinctum'' Carpenter, 1864. Both species have the same variantions in color. The very small shell is high-spired with a cylindrical shape. Its color varies between yellow to reddish-brown with some dark axial streaks. The slightly convex whorls are smooth, but show, under magnification, numerous, very fine spiral threads. This species shows great variations in strength and spacing of the spiral cords with, in some specimens, the major cords more prominent than norma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halistylus Columna
''Halistylus columna'' is a species of small sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.Rosenberg, G. (2012). ''Halistylus columna'' (Dall, 1890). Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=532895 on 2012-11-23 Description The height of the shell attains 5.8 mm, its diameter 1.9 mm. The small, blunt-tipped, polished shell has a subcylindrical shape. it is yellow, brown, salmon-colored, bluish gray, or streaked or banded with these colors. The shell contains seven whorls. The apex is flattish. The small nucleus is not differentiated. The whorls, after the second, are nearly equal in diameter. The suture is much appressed. The whorl is somewhat constricted in front of it. The sculpture consists only of faint incremental lines. The base of the shell is rounded. The aperture is rounded ovate, slightly oblique. The outer lip is continuous with the columella, which is raise ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halistylus Genecoani
''Halistylus genecoani'' is a species of sea snail, a marine gastropod mollusk in the family Trochidae, the top snails.Bouchet, P. (2012). ''Halistylus genecoani'' McLean, 1984. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=694618 on 2012-11-23 Distribution This species occurs in the Pacific Ocean off Baja California Baja California, officially the Free and Sovereign State of Baja California, is a state in Mexico. It is the northwesternmost of the 32 federal entities of Mexico. Before becoming a state in 1952, the area was known as the North Territory of B ..., Mexico. References External links World Register of Marine Species genecoani Gastropods described in 1984 {{Trochidae-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cantharidus
''Cantharidus'', common name the kelp shells, is a genus of sea snails, marine gastropod molluscs of the family Trochidae, the top shells.Rosenberg, G.; Bouchet, P. (2013). Cantharidus Montfort, 1810. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=204763 on 2014-01-12 Description The shell has an ovate-conic or pyramidal shape. It is imperforate, smooth or spirally sculptured outside, brilliantly iridescent within. The colors are generally bright and variegated. The aperture is less than half the length of shell, longer than wide, ovate. The columella is usually more or less folded or toothed near the base. The central tooth of the radula has a body with broadly expanded supporting wings, a narrowed peduncle or neck, which bears a simple cusp. This peduncle has on each side delicate wings. The lateral teeth number five on each side and have as peculiarity that they increase in size from the inner to the outer one. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siphonal Canal
The siphonal canal is an anatomical feature of the shells of certain groups of sea snails within the clade Neogastropoda. Some sea marine gastropods have a soft tubular anterior extension of the mantle called a siphon through which water is drawn into the mantle cavity and over the gill and which serves as a chemoreceptor to locate food. Siphonal canals allow for active transport of water to sensory organs inside the shell. Organisms without siphonal canals in their shells rely on passive or diffuse transport or water into their shell. Those with siphonal canals have a direct inhalant stream of water that interacts with sensory organs to detect concentration and direction of a stimulus, such as food or mates. In certain groups of carnivorous snails, where the siphon is particularly long, the structure of the shell has been modified in order to house and protect the soft structure of the siphon. Thus the siphonal canal is a semi-tubular extension of the aperture of the shell ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sculpture (mollusc)
Sculpture is a feature of many of the shells of mollusks. It is three-dimensional ornamentation on the outer surface of the shell, as distinct from either the basic shape of the shell itself or the pattern of colouration, if any. Sculpture is a feature found in the shells of gastropods, bivalves, and scaphopods. The word "sculpture" is also applied to surface features of the aptychus of ammonites, and to the outer surface of some calcareous opercula of marine gastropods such as some species in the family Trochidae. Sculpture can be concave or convex, incised into the surface or raised from it. Sometimes the sculpture has microscopic detailing. The term "sculpture" refers only to the calcareous outer layer of shell, and does not include the proteinaceous periostracum, which is in some cases textured even when the underlying shell surface is smooth. In many taxa, there is no sculpture on the shell surface at all, apart from the presence of fine growth lines. The sculp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Operculum (gastropod)
An 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, including the 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 (mollusc), 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 (mollusc), 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 are not capable of closing the shell aperture. Opercula have sometimes been modifie ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gastropod Shell
The gastropod shell is part of the body of many gastropods, including snails, 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, ostracum, is typically made of calcium carbonate (CaCO3) precipitated into an organic matrix ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants of an ancestral taxon are grouped together (i.e. Phylogeneti ... [...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] |
Family (biology)
Family (, : ) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". The delineation of what constitutes a family—or whether a described family should be acknowledged—is established and decided upon by active taxonomists. There are not strict regulations for outlining or acknowledging a family, yet in the realm of plants, these classifications often rely on both the vegetative and reproductive characteristics of plant species. Taxonomists frequently hold varying perspectives on these descriptions, leading to a lack of widespread consensus within the scientific community ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
