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Walleye
The walleye (''Sander vitreus'', synonym ''Stizostedion vitreum''), also called the yellow pike or yellow pickerel, is a freshwater perciform fish native to most of Canada and to the Northern United States. It is a North American close relative of the European zander, also known as the pikeperch. The walleye is sometimes called the yellow walleye to distinguish it from the blue walleye, which is a color morph that was once found in the southern Ontario and Quebec regions, but is now presumed extinct. However, recent genetic analysis of a preserved (frozen) 'blue walleye' sample suggests that the blue and yellow walleye were simply phenotypes within the same species and do not merit separate taxonomic classification. In parts of its range in English-speaking Canada, the walleye is known as a pickerel, though the fish is not related to the true pickerels, which are members of the family ''Esocidae''. Walleyes show a fair amount of variation across watersheds. In general, fis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walleye Weight Length Graph
The walleye (''Sander vitreus'', synonym ''Stizostedion vitreum''), also called the yellow pike or yellow pickerel, is a freshwater perciform fish native to most of Canada and to the Northern United States. It is a North American close relative of the European zander, also known as the pikeperch. The walleye is sometimes called the yellow walleye to distinguish it from the blue walleye, which is a color morph that was once found in the southern Ontario and Quebec regions, but is now presumed extinct. However, recent genetic analysis of a preserved (frozen) 'blue walleye' sample suggests that the blue and yellow walleye were simply phenotypes within the same species and do not merit separate taxonomic classification. In parts of its range in English-speaking Canada, the walleye is known as a pickerel, though the fish is not related to the true pickerels, which are members of the family ''Esocidae''. Walleyes show a fair amount of variation across watersheds. In general, fis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sander Vitreus
The walleye (''Sander vitreus'', synonym ''Stizostedion vitreum''), also called the yellow pike or yellow pickerel, is a freshwater perciform fish native to most of Canada and to the Northern United States. It is a North American close relative of the European zander, also known as the pikeperch. The walleye is sometimes called the yellow walleye to distinguish it from the blue walleye, which is a color morph that was once found in the southern Ontario and Quebec regions, but is now presumed extinct. However, recent genetic analysis of a preserved (frozen) 'blue walleye' sample suggests that the blue and yellow walleye were simply phenotypes within the same species and do not merit separate taxonomic classification. In parts of its range in English-speaking Canada, the walleye is known as a pickerel, though the fish is not related to the true pickerels, which are members of the family ''Esocidae''. Walleyes show a fair amount of variation across watersheds. In general, fis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Walleye Larva (8741578944)
The walleye (''Sander vitreus'', synonym ''Stizostedion vitreum''), also called the yellow pike or yellow pickerel, is a freshwater perciform fish native to most of Canada and to the Northern United States. It is a North American close relative of the European zander, also known as the pikeperch. The walleye is sometimes called the yellow walleye to distinguish it from the blue walleye, which is a color morph that was once found in the southern Ontario and Quebec regions, but is now presumed extinct. However, recent genetic analysis of a preserved (frozen) 'blue walleye' sample suggests that the blue and yellow walleye were simply phenotypes within the same species and do not merit separate taxonomic classification. In parts of its range in English-speaking Canada, the walleye is known as a pickerel, though the fish is not related to the true pickerels, which are members of the family ''Esocidae''. Walleyes show a fair amount of variation across watersheds. In general, fis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zander
The zander (''Sander lucioperca''), sander or pikeperch, is a species of ray-finned fish from the family Percidae, which includes the perches, ruffes and darters. It is found in freshwater and brackish habitats in western Eurasia. It is a popular game fish and has been introduced to a variety of localities outside its native range. It is the type species of the genus ''Sander''. Taxonomy The zander was first formally described in 1758 as ''Perca lucioperca'' by Carolus Linnaeus in volume 1 of the tenth edition of ''Systema Naturae'' and he gave the type locality as "European lakes". When Lorenz Oken (1779-1851) created the genus ''Sander'' he made ''Perca lucioperca'' its type species. The zander is part of the European clade within the genus ''Sander'' which split from a common ancestor with the North American clade, which the walleye (''S. vitreus'') and the sauger (''S. canadensis'') belong to, around 20.8 million years ago. Within the European clade the Volga pikeperch ('' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sauger
The sauger (''Sander canadensis'') is a freshwater perciform fish of the family Percidae that resembles its close relative, the walleye. The species is a member of the largest vertebrate order, the Perciformes.Jaeger, Matthew. 2004. Montana's Fish Species of Special Concern: Sauger. Montana Cooperative Fisheries Research Unit. http://www.fisheriessociety.org/AFSmontana/SSCpages/Sauger%20Status.htm. (Accessed May 2011). It is the most migratory percid species in North America.Kuhn et al. 2008. Habitat Use and Movement Patterns by Adult Saugers from fall to Summer in an Unimpounded Small-River System. ''North American Journal of Fisheries Management''. 28: 360-367. American Fisheries Society. 2008. Saugers have two dorsal fins; the first is spiny and the posterior dorsal fin is soft-rayed. Their paired fins are in the thoracic position and their caudal fin is truncated, which means squared off at the corners, a characteristic of the family Percidae. Another physical characteristic o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tapetum Lucidum
The ''tapetum lucidum'' ( ; ; ) is a layer of tissue in the eye of many vertebrates and some other animals. Lying immediately behind the retina, it is a retroreflector. It reflects visible light back through the retina, increasing the light available to the photoreceptors (although slightly blurring the image). The tapetum lucidum contributes to the superior night vision of some animals. Many of these animals are nocturnal, especially carnivores, while others are deep sea animals. Similar adaptations occur in some species of spiders. Haplorhine primates, including humans, are diurnal and lack a ''tapetum lucidum''. Function and mechanism Presence of a ''tapetum lucidum'' enables animals to see in dimmer light than would otherwise be possible. The ''tapetum lucidum'', which is iridescent, reflects light roughly on the interference principles of thin-film optics, as seen in other iridescent tissues. However, the ''tapetum lucidum'' cells are leucophores, not iridophores. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blue Walleye
The blue walleye (''Sander vitreus'' var. ''glaucus''), also called the blue pike, was a unique Polymorphism (biology), color morph (formerly considered a subspecies) of walleye which was Endemism, endemic to the Great Lakes of North America. morphometrics, Morphometric studies led biologists to classify the blue walleye as a separate species in 1926, although it was later downgraded to a subspecies. Listed as an endangered species by the United States in 1967, it was declared extinct in 1983. Genetic analyses conducted in the 21st century show that the blue walleye was not genetically different from the yellow walleye (''Sander vitreus''), rendering the Taxonomy (biology), taxon invalid. Species controversy The blue walleye was long considered to be different from the yellow walleye. Based on morphological study, Carl Leavitt Hubbs declared the blue walleye to be a separate species in 1926. The species was later downgraded to a subspecies. The blue walleye was a commercially v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Invertebrate
Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chordate subphylum Vertebrata. Familiar examples of invertebrates include arthropods, mollusks, annelids, echinoderms and cnidarians. The majority of animal species are invertebrates; one estimate puts the figure at 97%. Many invertebrate taxa have a greater number and variety of species than the entire subphylum of Vertebrata. Invertebrates vary widely in size, from 50 μm (0.002 in) rotifers to the 9–10 m (30–33 ft) colossal squid. Some so-called invertebrates, such as the Tunicata and Cephalochordata, are more closely related to vertebrates than to other invertebrates. This makes the invertebrates paraphyletic, so the term has little meaning in taxonomy. Etymology The word "invertebrate" comes from the Latin word ''vertebra'', whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diptera
Flies are insects of the order Diptera, the name being derived from the Greek δι- ''di-'' "two", and πτερόν ''pteron'' "wing". Insects of this order use only a single pair of wings to fly, the hindwings having evolved into advanced mechanosensory organs known as halteres, which act as high-speed sensors of rotational movement and allow dipterans to perform advanced aerobatics. Diptera is a large order containing an estimated 1,000,000 species including horse-flies, crane flies, hoverflies and others, although only about 125,000 species have been described. Flies have a mobile head, with a pair of large compound eyes, and mouthparts designed for piercing and sucking (mosquitoes, black flies and robber flies), or for lapping and sucking in the other groups. Their wing arrangement gives them great maneuverability in flight, and claws and pads on their feet enable them to cling to smooth surfaces. Flies undergo complete metamorphosis; the eggs are often laid on the l ... [...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] |
Yolk
Among animals which produce eggs, the yolk (; also known as the vitellus) is the nutrient-bearing portion of the egg whose primary function is to supply food for the development of the embryo. Some types of egg contain no yolk, for example because they are laid in situations where the food supply is sufficient (such as in the body of the host of a parasitoid) or because the embryo develops in the parent's body, which supplies the food, usually through a placenta. Reproductive systems in which the mother's body supplies the embryo directly are said to be matrotrophic; those in which the embryo is supplied by yolk are said to be lecithotrophic. In many species, such as all birds, and most reptiles and insects, the yolk takes the form of a special storage organ constructed in the reproductive tract of the mother. In many other animals, especially very small species such as some fish and invertebrates, the yolk material is not in a special organ, but inside the egg cell. As sto ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Embryo
An embryo is an initial stage of development of a multicellular organism. In organisms that reproduce sexually, embryonic development is the part of the life cycle that begins just after fertilization of the female egg cell by the male sperm cell. The resulting fusion of these two cells produces a single-celled zygote that undergoes many cell divisions that produce cells known as blastomeres. The blastomeres are arranged as a solid ball that when reaching a certain size, called a morula, takes in fluid to create a cavity called a blastocoel. The structure is then termed a blastula, or a blastocyst in mammals. The mammalian blastocyst hatches before implantating into the endometrial lining of the womb. Once implanted the embryo will continue its development through the next stages of gastrulation, neurulation, and organogenesis. Gastrulation is the formation of the three germ layers that will form all of the different parts of the body. Neurulation forms the nervous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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