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Mermaid's Purse
An egg case or egg capsule, often colloquially called a mermaid's purse, is the casing that surrounds the eggs of oviparous chondrichthyans. Living chondricthyans that produce egg cases include some sharks, skates and chimaeras. Egg cases typically contain one embryo, except for big skate and mottled skate egg cases, which contain up to 7 embryos. Oviparity is completely absent in the superorder Squalomorphi. Egg cases are also thought to have been produced by some extinct chondrichthyan groups, such as hybodonts and xenacanths. Description Egg cases are made of collagen protein strands, and are often described as feeling rough and leathery. Some egg cases have a fibrous material covering the outside of the egg case, thought to aid in attachment to substrate. Egg cases without a fibrous outer layer can be striated, bumpy, or smooth and glossy. With the exception of bullhead shark eggs, egg cases are typically rectangular in shape with projections, called horns, at ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Auger (drill)
An auger is a device to drill wood or other materials, consisting of a rotating metal shaft with a blade at the end that scrapes or cuts the wood. Types The classical design has a helical screw blade winding around the bottom end of the shaft. The lower edge of the blade is sharpened and scrapes the wood; the rest of the blade lifts the chips out of the way. It is powered with two hands, by a T-shaped handle attached to the top of the shaft. More modern versions have elaborated auger bits with multiple blades in various positions. Modern versions also have different means to drive the shaft, resulting in various tools such as braces, wheel drills (the "eggbeater" drill), and power drills. See also * Augerino * Gimlet References External links * {{Garden tools Agricultural machinery Gardening tools Mechanical hand tools ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scyliorhinus Canicula
''Scyliorhinus'' is a genus of catsharks in the family Scyliorhinidae. This genus is known in the fossil records from the Cretaceous period, late Albian age to the Pliocene epoch.Carrier, J. C.; Musick, J. A. & Heithaus, M. R. (2004)''Biology of Sharks and Their Relatives'' Species There are currently 16 recognized species in this genus: * ''Scyliorhinus boa'' Goode & T. H. Bean, 1896 (boa catshark) * '' Scyliorhinus cabofriensis'' K. D. A. Soares, U. L. Gomes & M. R. de Carvalho, 2016Soares, K.D.A., Gomes, U.L. & De Carvalho, M.R. (2016): Taxonomic review of catsharks of the ''Scyliorhinus haeckelii'' group, with the description of a new species (Chondrichthyes: Carcharhiniformes: Scyliorhinidae). ''Zootaxa, 4066 (5): 501-534.'' * '' Scyliorhinus canicula'' (Linnaeus, 1758) (small-spotted catshark) * '' Scyliorhinus capensis'' ( J. P. Müller & Henle, 1838) (yellowspotted catshark) * ''Scyliorhinus cervigoni'' Maurin & M. Bonnet, 1970 (West African catshark) * ''Scyliorhi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Small-spotted Catshark
The small-spotted catshark (''Scyliorhinus canicula''), also known as the sandy dogfish, lesser-spotted dogfish, rough-hound or morgay (in Scotland and Cornwall), is a catshark of the family Scyliorhinidae. It is found on the continental shelves and the uppermost continental slopes off the coasts of Norway and the British Isles south to Senegal and in the Mediterranean, between latitudes 63° N and 12° N. It can grow up to a length of , and it can weigh more than . It is found primarily over sandy, gravelly, or muddy bottoms from depths of a few metres down to .Rodriguez-Cabello, C., Sanchez, F., Olaso, I. 2007. Distribution patterns and sexual segregations of ''Scyliorhinus canicula'' (L.) in the Cantabrian Sea. ''Journal of Fish Biology''. 70: 1568–1586 ''S. canicula'' is one of the most abundant elasmobranchs in the northeast Atlantic and Mediterranean Sea. The majority of the populations are stable in most areas.Ballard, W., Mellinger, J., Lechenault, H. 2005. A series o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sea Floor
The seabed (also known as the seafloor, sea floor, ocean floor, and ocean bottom) is the bottom of the ocean. All floors of the ocean are known as seabeds. The structure of the seabed of the global ocean is governed by plate tectonics. Most of the ocean is very deep, where the seabed is known as the abyssal plain. Seafloor spreading creates mid-ocean ridges along the center line of major ocean basins, where the seabed is slightly shallower than the surrounding abyssal plain. From the abyssal plain, the seabed slopes upward toward the continents and becomes, in order from deep to shallow, the continental rise, slope, and shelf. The depth within the seabed itself, such as the depth down through a sediment core, is known as the "depth below seafloor". The ecological environment of the seabed and the deepest waters are collectively known, as a habitat for creatures, as the " benthos". Most of the seabed throughout the world's oceans is covered in layers of marine sediments. Cat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proscyllium
The genus ''Proscyllium'' is a small genus of finback catsharks in the family Proscylliidae. Species * '' Proscyllium habereri'' Hilgendorf, 1904 (graceful catshark) * '' Proscyllium magnificum'' Last A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts come in many styles and sizes, depending on the exact job they are designed for. Common variations ... & Vongpanich, 2004 (magnificent catshark) * '' Proscyllium venustum'' S. Tanaka, 1912 Shark genera Taxa named by Franz Martin Hilgendorf {{shark-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Finback Catshark
The finback catsharks are a small family, the Proscylliidae, of ground sharks. They can be found in warm seas worldwide and are often the most numerous and common shark in tropical regions. They are generally less than 1 m in length, and are slow-moving predators that feed on bony fish and small invertebrates. Although some bear live young, the majority lay eggs with almost fully developed young; these egg cases, known as "mermaid's purses", are unique in appearance to each species. Taxonomy Genus ''Proscyllium'' Hilgendorf 1904 * Graceful catshark (''Proscyllium habereri'') was first discovered by Hildendorf in 1901. * ''Proscyllium venustum'' is found in temperate regions. It is distributed along the Northwest Pacific, primarily Japan. These sharks are oviparous; they lay eggs in pairs in which the embryos feed solely on yolk. This species is considered harmless to humans. * Magnificent catshark (''Proscyllium magnificum'') A newly discovered species within the family Pro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scyliorhinidae
Scyliorhinidae is a Family (biology), family of sharks, one of a few families whose members share the common name catsharks, belonging to the Order (biology), order Carcharhiniformes, the ground sharks. Although they are generally known as catsharks, some species can also be called dogfish due to previous naming. However, a dogfish may generally be distinguished from a catshark as catsharks lay eggs while dogfish have live young. Like most bottom feeders, catsharks feed on benthic invertebrates and smaller fish. They are not harmful to humans. The family is paraphyletic, containing several distinct lineages that do not form a monophyletic group. Genera Scyliorhinidae includes the following genera: * ''Cephaloscyllium'' Theodore Gill, T. N. Gill, 1862 * ''Poroderma'' Andrew Smith (zoologist), A. Smith, 1838 * ''Scyliorhinus'' Henri Marie Ducrotay de Blainville, Blainville, 1816 Anatomy and appearance Scyliorhinidae catsharks may be distinguished by their elongated, cat- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zebra Shark
The zebra shark (''Stegostoma tigrinum'') is a species of carpet shark and the sole member of the family Stegostomatidae. It is found throughout the tropical Indo-Pacific, frequenting coral reefs and sandy flats to a depth of . Adult zebra sharks are distinctive in appearance, with five longitudinal ridges on a cylindrical body, a low caudal fin comprising nearly half the total length, and usually a pattern of dark spots on a pale background. Young zebra sharks under long have a completely different pattern, consisting of light vertical stripes on a brown background, and lack the ridges. This species attains a length of . Zebra sharks are nocturnal and spend most of the day resting motionless on the sea floor. At night, they actively hunt for molluscs, crustaceans, small bony fishes, and possibly sea snakes inside holes and crevices in the reef. Though solitary for most of the year, they form large seasonal aggregations. The zebra shark is oviparous: females produce several doz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bamboo Shark
The Hemiscylliidae are a family (biology), family of sharks in the order Orectolobiformes, commonly known as longtail carpet sharks and sometimes as bamboo sharks. They are found in shallow waters of the tropical Indo-Pacific. They are relatively small sharks, with the largest species reaching no more than in adult body length. They have elongated, cylindrical bodies, with short barbel (anatomy), barbels and large Spiracle (vertebrates), spiracles. As their common name suggests, they have unusually long tails, which exceed the length of the rest of their bodies. They are sluggish fish, feeding on bottom-dwelling invertebrates and smaller fish. Genera and species ''Chiloscyllium'' This genus is distinguished by a relatively long snout with subterminal nostrils. The eyes and supraorbital ridges are hardly elevated. The mouth is closer to the eyes than to the tip of the snout, with lower labial folds usually connected across the chin by a flap of skin. The pectoral fin, pectora ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chiloscyllium Punctatum Egg Sunshine International
''Chiloscyllium'' is a genus of sharks in the family Hemiscylliidae. This genus is distinguished by a relatively long snout with subterminal nostrils. The eyes and supraorbital ridges are hardly elevated. The mouth is closer to the eyes than to the tip of the snout, with lower labial folds usually connected across the chin by a flap of skin. The pectoral and pelvic fins are thin and not very muscular. No black hood on the head or large black spot on the side is present (though juveniles often are strongly marked with dark spots/bars). * '' Chiloscyllium arabicum'' Gubanov, 1980 (Arabian carpetshark) * '' Chiloscyllium burmensis'' Dingerkus & DeFino, 1983 (Burmese bamboo shark) * '' Chiloscyllium griseum'' J. P. Müller & Henle, 1838 (grey bamboo shark) * '' Chiloscyllium hasselti'' Bleeker, 1852 (Hasselt's bamboo shark) * '' Chiloscyllium indicum'' ( J. F. Gmelin, 1789) (slender bamboo shark) * '' Chiloscyllium plagiosum'' (Anonymous, referred to Bennett, 1830) (white-s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
