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Illex Illecebrosus NHM
''Illex'', commonly known as shortfin squids, is a genus of squid in the family Ommastrephidae and the only member of the subfamily Illicinae. It contains four species: * ''Illex argentinus'', Argentine shortfin squid * ''Illex coindetii'', southern shortfin squid * ''Illex illecebrosus'', northern shortfin squid * ''Illex oxygonius'', sharptail shortfin squid Molecular systematics A 2006 study evaluated the Taxonomy (biology), taxonomy of the squid genus ''Illex'' using molecular data from the cytochrome c oxidase subunit I (COI) gene. Traditionally, the genus has included four recognized species: ''Illex illecebrosus'', ''Illex coindetii'', ''Illex oxygonius'', and ''Illex argentinus''. ''I. argentinus'' is the most morphologically distinct and occurs in the South Atlantic Ocean, while the three North Atlantic species overlap geographically and display significant morphological variability, making them difficult to distinguish based on physical characteristics alone. The mol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ilex
''Ilex'' () or holly is a genus of over 570 species of flowering plants in the family Aquifoliaceae, and the only living genus in that family. ''Ilex'' has the most species of any woody dioecious angiosperm genus. The species are evergreen or deciduous trees, shrubs, and climbers from tropics to temperate zones worldwide. The type species is ''Ilex aquifolium'', the common European holly used in Christmas decorations and cards. Description The genus is widespread throughout the temperate and subtropical regions of the world. It includes species of trees, shrubs, and climbers, with evergreen or deciduous foliage and inconspicuous flowers. Its range was more extended in the Tertiary period and many species are adapted to laurel forest habitats. It occurs from sea level to more than with high mountain species. It is a genus of small, evergreen trees with smooth, glabrous, or pubescent branchlets. The plants are generally slow-growing with some species growing to tall. The type ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy adopted by most biological fields. The common ancestor may be an individual, a population, or a species (extinct or Extant taxon, extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed ''monophyletic'' (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming Taxon, taxa that are not clades; that is, taxa that are not Monophyly, monophyletic. Some of the relationships between organisms that the molecul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Illex
''Illex'', commonly known as shortfin squids, is a genus of squid in the family Ommastrephidae and the only member of the subfamily Illicinae. It contains four species: * '' Illex argentinus'', Argentine shortfin squid * '' Illex coindetii'', southern shortfin squid * '' Illex illecebrosus'', northern shortfin squid * '' Illex oxygonius'', sharptail shortfin squid Molecular systematics A 2006 study evaluated the taxonomy of the squid genus ''Illex'' using molecular data from the cytochrome c oxidase subunit I (COI) gene. Traditionally, the genus has included four recognized species: ''Illex illecebrosus'', ''Illex coindetii'', ''Illex oxygonius'', and ''Illex argentinus''. ''I. argentinus'' is the most morphologically distinct and occurs in the South Atlantic Ocean, while the three North Atlantic species overlap geographically and display significant morphological variability, making them difficult to distinguish based on physical characteristics alone. The molecular analysis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iridophores
Chromatophores are cells that produce color, of which many types are pigment-containing cells, or groups of cells, found in a wide range of animals including amphibians, fish, reptiles, crustaceans and cephalopods. Mammals and birds, in contrast, have a class of cells called melanocytes for coloration. Chromatophores are largely responsible for generating skin and eye colour in ectothermic animals and are generated in the neural crest during embryonic development. Mature chromatophores are grouped into subclasses based on their colour under white light: xanthophores (yellow), erythrophores (red), iridophores (reflective / iridescent), leucophores (white), melanophores (black/brown), and cyanophores (blue). While most chromatophores contain pigments that absorb specific wavelengths of light, the color of leucophores and iridophores is produced by their respective scattering and optical interference properties. Some species can rapidly change colour through mechanisms that trans ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fusiform
Fusiform (from Latin ''fusus'' ‘spindle’) means having a spindle (textiles), spindle-like shape that is wide in the middle and tapers at both ends. It is similar to the lemon (geometry), lemon-shape, but often implies a focal broadening of a structure that continues from one or both ends, such as an aneurysm on a blood vessel. Examples * Fusiform, a body shape common to many aquatic animals, characterized by being tapered at both the head and the tail * Fusiform, a classification of aneurysm * Fusiform bacteria (spindled rods, that is, fusiform bacilli), such as the Fusobacteriota * Fusiform cell (biology) * Fusiform face area, a part of the human visual system which seems to specialize in facial recognition * Fusiform gyrus, part of the temporal lobe of the brain * Fusiform muscle, where the fibres run parallel along the length of the muscle * Fusiform neuron, a spindle-shaped neuron References {{Reflist Geometric shapes See also * Streamliner, a fusiform hydro- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apomorphy And Synapomorphy
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 Ancient Greek (, ; ) includes the forms of the Greek language used in ancient Greece and the classical antiquity, ancien ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nocturnality
Nocturnality is a behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnal meaning the opposite. Nocturnal creatures generally have highly developed senses of hearing, smell, and specially adapted eyesight. Some animals, such as ferrets, have eyes that can adapt to both low-level and bright day levels of illumination (see metaturnal). Others, such as bushbabies and (some) bats, can function only at night. Many nocturnal creatures including tarsiers and some owls have large eyes in comparison with their body size to compensate for the lower light levels at night. More specifically, they have been found to have a larger cornea relative to their eye size than diurnal creatures to increase their : in the low-light conditions. Nocturnality helps wasps, such as ''Apoica flavissima'', avoid hunting in intense sunlight. Diurnal animals, including humans (except for ni ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radula
The radula (; : radulae or radulas) is an anatomical structure used by mollusks for feeding, sometimes compared to a tongue. It is a minutely toothed, chitinous ribbon, which is typically used for scraping or cutting food before the food enters the esophagus. The radula is unique to the mollusks, and is found in every class of mollusk except the bivalves, which instead use cilia, waving filaments that bring minute organisms to the mouth. Within the gastropods, the radula is used in feeding by both herbivorous and carnivorous snails and slugs. The arrangement of teeth ( denticles) on the radular ribbon varies considerably from one group to another. In most of the more ancient lineages of gastropods, the radula is used to graze, by scraping diatoms and other microscopic algae off rock surfaces and other substrates. Predatory marine snails such as the Naticidae use the radula plus an acidic secretion to bore through the shell of other mollusks. Other predatory marine snails, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shrimp
A shrimp (: shrimp (American English, US) or shrimps (British English, UK)) is a crustacean with an elongated body and a primarily Aquatic locomotion, swimming mode of locomotion – typically Decapods belonging to the Caridea or Dendrobranchiata, although some Shrimp#Non-decapods, crustaceans outside of this order are also referred to as "shrimp". Any small crustacean may also be referred to as "shrimp", regardless of resemblance. More narrow definitions may be restricted to Caridea, to smaller species of either of the aforementioned groups, or only the Marine life, marine species. Under a broader definition, ''shrimp'' may be synonymous with prawn, covering stalk-eyed swimming crustaceans with long, narrow muscular tails (Abdomen#Arthropoda, abdomens), long whiskers (Antenna (biology), antennae), and slender, Biramous, biramous legs. They swim forward by paddling the swimmerets on the underside of their abdomens, although their escape response is typically repeated flicks wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krill
Krill ''(Euphausiids)'' (: krill) are small and exclusively marine crustaceans of the order (biology), order Euphausiacea, found in all of the world's oceans. The name "krill" comes from the Norwegian language, Norwegian word ', meaning "small Fry (biology), fry of fish", which is also often attributed to species of fish. Krill are considered an important trophic level connection near the bottom of the food chain. They feed on phytoplankton and, to a lesser extent, zooplankton, and are also the main source of food for many larger animals. In the Southern Ocean, one species, the Antarctic krill, makes up an estimated biomass (ecology), biomass of around 379 million tonnes, making it among the species with the largest total biomass. Over half of this biomass is eaten by whales, Pinniped, seals, penguins, seabirds, squid, and fish each year. Most krill species display large diel vertical migration, daily vertical migrations, providing food for predators near the surface at night an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustacean
Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthropods including decapods (shrimps, prawns, crabs, lobsters and crayfish), seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, opossum shrimps, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods (insects and entognathans) emerged deep in the Crustacean group, with the completed pan-group referred to as Pancrustacea. The three classes Cephalocarida, Branchiopoda and Remipedia are more closely related to the hexapods than they are to any of the other crustaceans ( oligostracans and multicrustaceans). The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
