Cirrate Shell

picture info	Cirrate Shell Cirrate octopuses possess a well-developed internal shell that supports their muscular swimming fins. This is in contrast to the more familiar, finless, incirrate octopuses, in which the shell remnant is either present as a pair of stylets or absent altogether. The cirrate shell is quite unlike that of any other living cephalopod group and has its own dedicated set of descriptive terms. It is usually roughly arch- or saddle-shaped and is rather soft, being similar in consistency to cartilage. Each of the eight extant cirrate genera is characterised by a distinct shell morphology: * Cirroteuthidae '' Cirroteuthis'' — saddle-shaped, with large wings '' Cirrothauma'' — butterfly-shaped * Opisthoteuthidae '' Cirroctopus'' — V-shaped, lateral wings tapering to fine points '' Cryptoteuthis'' — U-shaped, each lateral wing ending in broad lobe with pointed projection ''Grimpoteuthis'' — U-shaped, lateral wings ending bluntly '' Luteuthis'' — W-shaped '' Opi ... [...More Info...] [...Related Items...] OR:** [Wikipedia] [Google] [Baidu]
	Grimpoteuthis Innominata 73 Mm ML ''Grimpoteuthis'' is a genus of pelagic umbrella octopuses known as the dumbo octopuses. The name "dumbo" originates from their resemblance to the title character of Disney's 1941 film ''Dumbo'', having a prominent ear-like fin which extends from the Mantle (mollusc), mantle above each eye. There are 17 species recognized in the genus. Prey include crustaceans, bivalves, worms and copepods. The average life span of various ''Grimpoteuthis'' species is 3 to 5 years. Species and taxonomy As noted above, many species collected on the Challenger expedition, ''Challenger'' expedition were initially classified in the genera ''Cirroteuthis'' and ''Stauroteuthis.'' Several species formerly classified as ''Grimpoteuthis'' were moved to genera ''Cirroctopus'' and ''Opisthoteuthis''. A new family, Grimpoteuthididae (alternatively spelled Grimpoteuthidae), has been proposed to accommodate ''Grimpoteuthis'' and those of genera ''Enigmatiteuthis'', ''Cryptoteuthis'', and ''Luteuthis''. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Cryptoteuthis ''Cryptoteuthis brevibracchiata'', the short-arm flapjack octopod, is a deepwater species of Octopus, octopod. It is the only species in the monotypy, monotypic genus ''Cryptoteuthis'' one of the Cirrina, cirrate octopuses of the Family (biology), family Opisthoteuthidae, the umbrella octopuses. It is known from a single specimen which was collected in the northeastern Atlantic Ocean. It has characteristics which are shared with two other genera in the Opisthoteuthidae, ''Opisthoteuthis'' and ''Grimpoteuthis'', but is sufficiently distinctive from either of these to warrant the erection of a new genus. Description ''Cryptoteuthis brevibracchiata'' is a bell-shaped octopus with a semi-gelatinous, semi-transparent body, except for the dark tips of the oral web and the tips of the fins. The fins are small and round, and their length is equal to half the width of the head. It has short arms, each with a single row of small, broad suckers and with a double row of Cirrus (biology), ci ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Stylet (octopus) Stylet may refer to: An archaeological term for a type of flint tool found in Lebanon, also known as a Minet ed Dhalia point Stylet (anatomy) A stylet is a hard, sharp, anatomical structure found in some invertebrates. For example, the word ''stylet'' or stomatostyle is used for the primitive piercing mouthparts of some nematodes and some nemerteans. In these groups the stylet is a h ... , a hard, sharp anatomical structure In the medical industry a stylet is a slender medical probe or device. For example, stylets used to facilitate tracheal intubation – see {{disambig ... [...More Info...] [...Related Items...] OR:* [Wikipedia] [Google] [Baidu]
picture info	Palaeoctopus Newboldi ''Palaeoctopus newboldi'' is an extinct basal octopod that lived in the Late Cretaceous, approximately 89 to 71 million years ago. Fossil material assigned to this species originates from the Mount Hajoula region in Lebanon. The holotype was found below the Old Covent, Sahel-el-Alma, Mount Lebanon and is deposited at the Natural History Museum in London. It might belong to the Cirrina or be more basal in the Octopoda. Specimens from the Turonian of Vallecino, Mexico, originally described as ''P. pelagicus'', are reinterpreted to be portions of a coelacanth. See also ''Jeletzkya douglassae'' '' Proteroctopus ribeti'' '' Vampyronassa rhodanica'' 2009 extinct fossil octopus discoveries Arthropods Cephalopods Three new species of extinct Octopoda discovered in 2009. The species – '' Keuppia hyperbolaris'', '' Keuppia levante'', and '' Styletoctopus annae'' – lived about 95 million years ago, and bear a strong resembla ... References External linksThe Oct ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Late Cretaceous The Late Cretaceous (100.5–66 Ma) is the younger of two epochs into which the Cretaceous Period is divided in the geologic time scale. Rock strata from this epoch form the Upper Cretaceous Series. The Cretaceous is named after ''creta'', the Latin word for the white limestone known as chalk. The chalk of northern France and the white cliffs of south-eastern England date from the Cretaceous Period. Climate During the Late Cretaceous, the climate was warmer than present, although throughout the period a cooling trend is evident. The tropics became restricted to equatorial regions and northern latitudes experienced markedly more seasonal climatic conditions. Geography Due to plate tectonics, the Americas were gradually moving westward, causing the Atlantic Ocean to expand. The Western Interior Seaway divided North America into eastern and western halves; Appalachia and Laramidia. India maintained a northward course towards Asia. In the Southern Hemisphere, Australia and Ant ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Derived Trait In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have evolved in their most recent common ancestor. ) In cladistics, synapomorphy implies homology. Examples of apomorphy are the presence of erect gait, fur, the evolution of three middle ear bones, and mammary glands in mammals but not in other vertebrate animals such as amphibians or reptiles, which have retained their ancestral traits of a sprawling gait and lack of fur. Thus, these derived traits are also synapomorphies of mammals in general as they are not shared by other vertebrate animals. Etymology The word —coined by German entomologist Willi Hennig—is derived from the Ancient Greek words (''sún''), meaning "with, together"; (''apó''), meaning "away from"; and (''morphḗ''), meaning "shape, form". Clade analysis Th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Plesiomorphy In phylogenetics, a plesiomorphy ("near form") and symplesiomorphy are synonyms for an ancestral character shared by all members of a clade, which does not distinguish the clade from other clades. Plesiomorphy, symplesiomorphy, apomorphy, and synapomorphy, all mean a trait shared between species because they share an ancestral species. Apomorphic and synapomorphic characteristics convey much information about evolutionary clades and can be used to define taxa. However, plesiomorphic and symplesiomorphic characteristics cannot. The term ''symplesiomorphy'' was introduced in 1950 by German entomologist Willi Hennig. Examples A backbone is a plesiomorphic trait shared by birds and mammals, and does not help in placing an animal in one or the other of these two clades. Birds and mammals share this trait because both clades are descended from the same far distant ancestor. Other clades, e.g. snakes, lizards, turtles, fish, frogs, all have backbones and none are either birds n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Stauroteuthis ''Stauroteuthis'' is a genus of deepwater octopus, a cephalopod mollusk. This is the only genus in the family Stauroteuthidae, and only two species have been described in this genus. The organisms live below water depth; although sometimes found as deep as underwater, they generally live at a water depth of around . They do not possess a radula. The stauroteuthids have the distinction of being one of the few bioluminescent octopuses; some of the muscle cells that control the suckers in most species have been replaced with photophores which are believed to fool prey by directing them towards the mouth. Species * ''Stauroteuthis gilchristi'' is only known from two localities in the south Atlantic; these two localities may even represent different species. * ''Stauroteuthis syrtensis'' is widespread in the North Atlantic. The population size of ''S. syrtensis'' is unknown. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Stauroteuthidae ''Stauroteuthis'' is a genus of deepwater octopus, a cephalopod mollusk. This is the only genus in the family Stauroteuthidae, and only two species have been described in this genus. The organisms live below water depth; although sometimes found as deep as underwater, they generally live at a water depth of around . They do not possess a radula. The stauroteuthids have the distinction of being one of the few bioluminescent octopuses; some of the muscle cells that control the suckers in most species have been replaced with photophores which are believed to fool prey by directing them towards the mouth. Species * '' Stauroteuthis gilchristi'' is only known from two localities in the south Atlantic; these two localities may even represent different species. * '' Stauroteuthis syrtensis'' is widespread in the North Atlantic. The population Population typically refers to the number of people in a single area, whether it be a city or town, region, country, continent, or the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
picture info	Opisthoteuthis ''Opisthoteuthis'' is a genus of cirrate octopuses, sometimes known as flapjack octopuses, which are found in all the world's oceans. Behavior Like other cirrates, octopuses in Opisthoteuthis are generally small, and many dwell in the deep sea. They have cirri on their arms, internal shells to support their bodies, and muscular fins for steering. Like octopuses of Grimpoteuthis ''Grimpoteuthis'' is a genus of pelagic umbrella octopuses known as the dumbo octopuses. The name "dumbo" originates from their resemblance to the title character of Disney's 1941 film ''Dumbo'', having a prominent ear-like fin which extends from ..., opisthoteuthids have been seen resting or crawling on the seafloor. Species The following 24 species have been placed in ''Opisthoteuthis'': Notes References External links * * {{Taxonbar, from=Q3816282 Octopuses Cephalopod genera ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Luteuthis ''Luteuthis'' is a small genus of cirrate octopuses currently placed in the family Opisthoteuthidae. There are two species classified in this genus one from waters west of New Zealand and the other from the South China Sea. Taxonomy ''Luteuthis'' are characterized by several unique features. The body is relatively elongate, extensively gelatinous and lacking areolar spots. The paired fins are laterally placed, and supported by a W-shaped internal shell with the shell wings bearing in-rolled margins and tapering to acute points. The arms are narrow and connected by simple webbing, there is no web nodule acting as a web attachment point. The suckers are crenulated (around the aperture opening) and are flanked by rows of short cirri (cirri about half as long as the sucker diameter). The gills resemble a "half-orange" and have seven lamellae. ''Luteuthis'' species have a well developed radula as well as palatine teeth on the palps flanking the radula, and the digestive gland is bi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]
	Grimpoteuthis ''Grimpoteuthis'' is a genus of pelagic umbrella octopuses known as the dumbo octopuses. The name "dumbo" originates from their resemblance to the title character of Disney's 1941 film ''Dumbo'', having a prominent ear-like fin which extends from the mantle above each eye. There are 17 species recognized in the genus. Prey include crustaceans, bivalves, worms and copepods. The average life span of various ''Grimpoteuthis'' species is 3 to 5 years. Species and taxonomy As noted above, many species collected on the ''Challenger'' expedition were initially classified in the genera '' Cirroteuthis'' and '' Stauroteuthis.'' Several species formerly classified as ''Grimpoteuthis'' were moved to genera '' Cirroctopus'' and '' Opisthoteuthis''. A new family, Grimpoteuthididae (alternatively spelled Grimpoteuthidae), has been proposed to accommodate ''Grimpoteuthis'' and those of genera ''Enigmatiteuthis'', ''Cryptoteuthis'', and ''Luteuthis''. The persistent confusion and disparit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu]