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Epiactis Ritteri
''Epiactis ritteri'', the sandy anemone or Ritter's brooding anemone, is a species of sea anemone in the family Actiniidae. It is found in the Pacific Ocean on the western coast of North America in the shallow sub-littoral zone. Description ''Epiactis ritteri'' is very flat when retracted with a wide, flared pedal base, and can measure wide and high. The column is unarmed with acontia and has no tubercles, but has some small adhesive warts to which sand or other fragments may stick. There may be radiating lines on the pedal disc at the base of the column. There are broad white markings on the oral disc near the base of the tentacles but these do not extend as far as the mouth, a fact which distinguishes it from the rather similar ''Epiactis prolifera''. The general colour of this anemone is reddish-brown to brown. Biology It is likely that this species is largely inbred because it does not have a planktonic stage in its life history. It is a simultaneous hermaphrodite, produci ... [...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] |
Family (biology)
Family ( la, familia, plural ') 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". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Actiniidae
Actiniidae is the largest family of sea anemones, to which most common, temperate, shore species belong. Most members of this family do not participate in symbioses with fishes. Three exceptions are the bubble-tip anemone (with anemonefish and certain cardinalfish), snakelocks anemone (with Incognito goby) and ''Urticina piscivora'' (with painted greenling). The systematics of Actiniidae is often quite difficult. The problem with identification of genera within this family is that most species are readily distinguishable when alive but when fixated lose their color and some other features. Arrangement of tentacles is important in defining genera for Actiniaria families. There may be one tentacle per space between mesenteries or there may be more than one tentacle between each two mesenteries. Members of the family Actiniidae have one tentacle per space. Genera Genera in this family include: * ''Actinia'' Linnaeus, 1767 * '' Actinioides'' Haddon & Shackleton, 1893 * '' Actino ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epiactis Prolifera
''Epiactis prolifera'', the brooding, proliferating or small green anemone, is a species of marine invertebrate in the family Actiniidae.Fautin, D. (2010). ''Epiactis prolifera'' Verrill, 1869. Accessed through: World Register of Marine Species at http://www.marinespecies.org/aphia.php?p=taxdetails&id=283435 on 2011-07-20 It is found in the north-eastern Pacific. It has a feature rare among animals in that all individuals start life as females but develop testes later in their lives to become hermaphrodites. Description The brooding anemone grows to three centimetres high and up to five centimetres in diameter and varies in colour, usually being greenish-brown but sometimes brown, pink, red or dull green. There are fine white lines starting at the mouth and spreading radially across the oral disc and further white lines occur on the column and pedal disc. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hermaphrodite
In reproductive biology, a hermaphrodite () is an organism that has both kinds of reproductive organs and can produce both gametes associated with male and female sexes. Many Taxonomy (biology), taxonomic groups of animals (mostly invertebrates) do not have separate sexes. In these groups, hermaphroditism is a normal condition, enabling a form of sexual reproduction in which either partner can act as the female or male. For example, the great majority of tunicata, tunicates, pulmonate molluscs, opisthobranch, earthworms, and slugs are hermaphrodites. Hermaphroditism is also found in some fish species and to a lesser degree in other vertebrates. Most plants are also hermaphrodites. Animal species having different sexes, male and female, are called Gonochorism, gonochoric, which is the opposite of hermaphrodite. There are also species where hermaphrodites exist alongside males (called androdioecy) or alongside females (called gynodioecy), or all three exist in the same species ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Larva
A larva (; plural larvae ) is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle. The larva's appearance is generally very different from the adult form (''e.g.'' caterpillars and butterflies) including different unique structures and organs that do not occur in the adult form. Their diet may also be considerably different. Larvae are frequently adapted to different environments than adults. For example, some larvae such as tadpoles live almost exclusively in aquatic environments, but can live outside water as adult frogs. By living in a distinct environment, larvae may be given shelter from predators and reduce competition for resources with the adult population. Animals in the larval stage will consume food to fuel their transition into the adult form. In some organisms like polychaetes and barnacles, adults are immobil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tentacle
In zoology, a tentacle is a flexible, mobile, and elongated organ present in some species of animals, most of them invertebrates. In animal anatomy, tentacles usually occur in one or more pairs. Anatomically, the tentacles of animals work mainly like muscular hydrostats. Most forms of tentacles are used for grasping and feeding. Many are sensory organs, variously receptive to touch, vision, or to the smell or taste of particular foods or threats. Examples of such tentacles are the eyestalks of various kinds of snails. Some kinds of tentacles have both sensory and manipulatory functions. A tentacle is similar to a cirrus, but a cirrus is an organ that usually lacks the tentacle's strength, size, flexibility, or sensitivity. A nautilus has cirri, but a squid has tentacles. Invertebrates Molluscs Many molluscs have tentacles of one form or another. The most familiar are those of the pulmonate land snails, which usually have two sets of tentacles on the head: when extended ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Animals Described In 1902
Animals are multicellular, eukaryotic organisms in the biological kingdom Animalia. With few exceptions, animals consume organic material, breathe oxygen, are able to move, can reproduce sexually, and go through an ontogenetic stage in which their body consists of a hollow sphere of cells, the blastula, during embryonic development. Over 1.5 million living animal species have been described—of which around 1 million are insects—but it has been estimated there are over 7 million animal species in total. Animals range in length from to . They have complex interactions with each other and their environments, forming intricate food webs. The scientific study of animals is known as zoology. Most living animal species are in Bilateria, a clade whose members have a bilaterally symmetric body plan. The Bilateria include the protostomes, containing animals such as nematodes, arthropods, flatworms, annelids and molluscs, and the deuterostomes, containing the echinoderms and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
