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Anopla
Anopla (for changes in taxonomy, see reference from 2019) has long been used as name for a class of marine worms of the phylum Nemertea, characterized by the absence of stylets on the proboscis, the mouth being below or behind the brain, and by having separate openings for the mouth and proboscis. The other long used class of Nemertea are the Enopla (for changes in taxonomy, see reference from 2019). Although Anopla is a paraphyletic grouping, it is used in almost all Scientific classifications. Anopla is divided into two orders: Palaeonemertea and Heteronemertea. Norenburg, J.; Gibson, R.; Herrera Bachiller, A.; Strand, M. (2019). World Nemertea Database. Anopla. Accessed through: World Register of Marine Species at: http://www.marinespecies.org/aphia.php?p=taxdetails&id=1293 on 2019-11-07 Palaeonemertea may be para- or polyphyletic, consisting of 3-5 groupings and totalling about 100 species. These worms have several apparently simple features and, as their name suggests, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nemertea
Nemertea is a phylum of animals also known as ribbon worms or proboscis worms, consisting of 1300 known species. Most ribbon worms are very slim, usually only a few millimeters wide, although a few have relatively short but wide bodies. Many have patterns of yellow, orange, red and green coloration. The foregut, stomach and intestine run a little below the midline of the body, the anus is at the tip of the tail, and the mouth is under the front. A little above the gut is the rhynchocoel, a cavity which mostly runs above the midline and ends a little short of the rear of the body. All species have a proboscis which lies in the rhynchocoel when inactive but everts to emerge just above the mouth to capture the animal's prey with venom. A highly extensible muscle in the back of the rhynchocoel pulls the proboscis in when an attack ends. A few species with stubby bodies filter feed and have suckers at the front and back ends, with which they attach to a host. The brain is a rin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeonemertea
Palaeonemertea is a class of primitive nemertean worm. It may be para- or polyphyletic, consisting of three to five clades and totalling about 100 species. These worms have several apparently simple features and, as their name suggests, they are often considered to be the most primitive nemerteans. The primary body-wall musculature consists of an outer circular layer overlying a longitudinal layer. The group includes genera such as '' Cephalothrix'' in which the nerve cords are inside the body-wall longitudinal muscle, and ''Tubulanus ''Tubulanus'' is a genus of primitive nemertean worms in the order Palaeonemertea. Species The World Register of Marine Species includes the following species in the genus: * '' Tubulanus albocinctus'' (Coe, 1904) * '' Tubulanus annulatus'' (Mo ...'', in which the nerve cords are between the outer circular muscle and the epidermis. Tubulanids are commonly encountered in rocky areas of intertidal zones in the northern hemisphere. They are often ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Enopla
Enopla is one of the classes of the worm phylum Nemertea, characterized by the presence of a peculiar armature of spines or plates in the proboscis. Evolution and systematics The record of nemerteans is extremely sparse, as would be expected from a soft-bodied animal. The Cambrian fossil, '' Amiskwia'', has been interpreted as a nemertean based on its resemblance to some pelagic ribbon worms; however, this interpretation is disputed by many paleontologists. The enoplan nemerteans have been regarded as highly derived based on a more complicated muscle arrangement in the body wall and a more complex nervous system. However, whether this is a plesiomorphic or apomorphic character is not clear, and recent molecular studies are inconclusive in this respect. Class Enopla used to be divided in two subclasses, Hoplonemertea and Bdellonemertea, but recent phylogenetic analyses based on nucleotide sequences show that Bdellonemertea should be included in Hoplonemertea. Hoplonemertea ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Heteronemertea
Heteronemertea is a monophyletic order of about 500 species of nemertean worm. It contains genera such as ''Lineus'' and ''Cerebratulus'', and includes the largest and most muscular nemerteans. Almost all heteronemerteans have three primary body-wall muscle strata: an outer longitudinal, a middle circular, and an inner longitudinal. The lateral nerve cords are outside the circular muscle, as in palaeonemerteans, but separated from the epidermis by the usually well-developed outer longitudinal muscle. Taxonomy Families within the order Heteronemertea include: * Baseodiscidae * Cerebratulidae * Gorgonorhynchidae *Lineidae Lineidae is a family of nemertean worms. It contains the following genera: * '' Aetheolineus'' Senz, 1993 * '' Ammolineus'' Senz, 2001 * ''Antarctolineus'' Muller & Scripcariu, 1964 * ''Apatronemertes'' Wilfert & Gibson, 1974 * '' Australineus'' ... * Mixolineidae * Panorhynchidae * Poliopsiidae * Polybrachiorhynchidae * Pussylineidae * Riseriellidae * Vale ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral Nerve Cord
The ventral nerve cord is a major structure of the invertebrate central nervous system. It is the functional equivalent of the vertebrate spinal cord. The ventral nerve cord coordinates neural signaling from the brain to the body and vice versa, integrating sensory input and locomotor output. Decapitated insects can still walk, groom, and mate, illustrating that the circuitry of the ventral nerve cord is sufficient to perform complex motor programs without brain input. Structure The ventral nerve cord runs down the Anatomical terms of location, ventral ("belly", as opposed to back) plane of the organism. It contains ascending and Descending neuron, descending neurons that relay information to and from the brain, Motor neuron, motor neurons that project into the body and synapse onto muscles, Sensory neuron, sensory neurons that receive information from the body and environment, and Interneuron, interneurons that coordinate circuitry of all of these neurons. Ventral nerve cord ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pennsylvanian (geology)
The Pennsylvanian ( , also known as Upper Carboniferous or Late Carboniferous) is, in the International Commission on Stratigraphy, ICS geologic timescale, the younger of two period (geology), subperiods (or upper of two system (stratigraphy), subsystems) of the Carboniferous Period. It lasted from roughly . As with most other geochronology, geochronologic units, the stratum, rock beds that define the Pennsylvanian are well identified, but the exact date of the start and end are uncertain by a few hundred thousand years. The Pennsylvanian is named after the U.S. state of Pennsylvania, where the coal-productive beds of this age are widespread. The division between Pennsylvanian and Mississippian (geology), Mississippian comes from North American stratigraphy. In North America, where the early Carboniferous beds are primarily marine limestones, the Pennsylvanian was in the past treated as a full-fledged geologic period between the Mississippian and the Permian. In parts of Europe, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muscular
Skeletal muscles (commonly referred to as muscles) are organs of the vertebrate muscular system and typically are attached by tendons to bones of a skeleton. The muscle cells of skeletal muscles are much longer than in the other types of muscle tissue, and are often known as muscle fibers. The muscle tissue of a skeletal muscle is striated – having a striped appearance due to the arrangement of the sarcomeres. Skeletal muscles are voluntary muscles under the control of the somatic nervous system. The other types of muscle are cardiac muscle which is also striated and smooth muscle which is non-striated; both of these types of muscle tissue are classified as involuntary, or, under the control of the autonomic nervous system. A skeletal muscle contains multiple fascicles – bundles of muscle fibers. Each individual fiber, and each muscle is surrounded by a type of connective tissue layer of fascia. Muscle fibers are formed from the fusion of developmental myoblasts in a pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cerebratulus
''Cerebratulus'' is a genus of nemerteans belonging to the family Lineidae. The genus has cosmopolitan distribution. Species Species: *''Cerebratulus acutus'' *''Cerebratulus lacteus'' *''Cerebratulus marginatus ''Cerebratulus marginatus'' is a proboscis worm in the family Lineidae. This ribbon worm has an Arctic distribution, and in the North Atlantic Ocean ranges as far south as Cape Cod and the Mediterranean Sea while in the Pacific Ocean it extends s ...'' References Lineidae Nemertea genera {{nemertean-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lineus
''Lineus'' is a genus of nemertine worms, including the bootlace worm, arguably the longest animal alive. ''Lineus'' contains the following species: *'' Lineus acutifrons'' Southern, 1913 *'' Lineus albifrons'' Coe, 1934 *'' Lineus albocinctus'' Verrill, 1900 *'' Lineus albonasus'' Verrill, 1900 *'' Lineus alborostratus'' Takakura, 1898 *''Lineus albus'' *'' Lineus alienus'' Bürger, 1895 *'' Lineus anellatus'' *'' Lineus angulosus'' Korotkevich, 1978 *'' Lineus arenicola'' (Verrill, 1873) *'' Lineus atradentis'' Korotkevich, 1978 *'' Lineus atrocaeruleus'' (Schmarda, 1859) *'' Lineus auripunctatus'' (Grube, 1855) *'' Lineus aurostriatus'' (Bürger, 1890) *''Lineus australis'' *'' Lineus autrani'' Joubin, 1905 *'' Lineus bergendali'' Senz, 1996 *'' Lineus bilineatus'' (Renier, 1804) *''Lineus binigrilinearis'' Gibson, 1990 *''Lineus bioculatus'' Sundberg & Gibson, 1995 *''Lineus bipunctatus'' Takakura, 1898 *''Lineus bonaerensis'' Moretto, 1971 *''Lineus boutani'' (Joubin, 1893) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Monophyly
In cladistics for a group of organisms, monophyly is the condition of being a clade—that is, a group of taxa composed only of a common ancestor (or more precisely an ancestral population) and all of its lineal descendants. Monophyletic groups are typically characterised by shared derived characteristics ( synapomorphies), which distinguish organisms in the clade from other organisms. An equivalent term is holophyly. The word "mono-phyly" means "one-tribe" in Greek. Monophyly is contrasted with paraphyly and polyphyly as shown in the second diagram. A ''paraphyletic group'' consists of all of the descendants of a common ancestor minus one or more monophyletic groups. A '' polyphyletic group'' is characterized by convergent features or habits of scientific interest (for example, night-active primates, fruit trees, aquatic insects). The features by which a polyphyletic group is differentiated from others are not inherited from a common ancestor. These definitions have taken ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tubulanus
''Tubulanus'' is a genus of primitive nemertean worms in the order Palaeonemertea. Species The World Register of Marine Species The World Register of Marine Species (WoRMS) is a taxonomic database that aims to provide an authoritative and comprehensive list of names of marine organisms. Content The content of the registry is edited and maintained by scientific specialist ... includes the following species in the genus: * '' Tubulanus albocinctus'' (Coe, 1904) * '' Tubulanus annulatus'' (Montagu, 1804) * '' Tubulanus aureus'' (Joubin, 1904) * '' Tubulanus borealis'' Friedrich, 1936 * '' Tubulanus capistratus'' (Coe, 1901) * '' Tubulanus cingulatus'' (Coe, 1904) * '' Tubulanus ezoensis'' Yamaoka, 1940 * '' Tubulanus floridanus'' Coe, 1951 * '' Tubulanus frenatus'' (Coe, 1904) * '' Tubulanus groenlandicus'' (Bergendal, 1902) * '' Tubulanus holorhynchocoelomicus'' Friedrich, 1958 * '' Tubulanus hylbomi'' Gibson & Sundberg, 1999 * '' Tubulanus linearis'' (McIntosh, 1874) * '' Tubul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Order (biology)
Order ( la, wikt:ordo#Latin, ordo) is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between Family_(biology), family and Class_(biology), class. In biological classification, the order is a taxonomic rank used in the classification of organisms and recognized by the nomenclature codes. An immediately higher rank, superorder, is sometimes added directly above order, with suborder directly beneath order. An order can also be defined as a group of related families. What does and does not belong to each order is determined by a taxonomist, as is whether a particular order should be recognized at all. Often there is no exact agreement, with different taxonomists each taking a different position. There are no hard rules that a taxonomist needs to follow in describing or recognizing an order. Some taxa are accepted almost universally, while others are recognized only rarely. The name of an order is usually written with a capital letter. Fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
