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Scoliodon
''Scoliodon'' is a genus of requiem sharks in the family Carcharhinidae. It was formerly thought to include only a single Indo-Pacific species, the spadenose shark (''S. laticaudus''), but recent taxonomic research has found an additional species, the Pacific spadenose shark (''S. macrorhynchos''). Location The ''Scoliodon'' genus of sharks has been found mainly in the Indo-West Pacific oceans from the west coasts of Africa to south of Japan. Biology ''Scoliodon'' has an elongated, spindle-shaped body tapered at the ends, making it a very fast swimmer. The trunk and tail are laterally compressed, while the head region is dorsoventrally compressed. The entire body is covered by an exoskeleton of placoid scales. The mouth is located on the ventral side and is bound on both sides by jaws. It has two rows of homodont or polyphyodont teeth, which are homologous to the placoid scales A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of most j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scoliodon Laticaudus
The spadenose shark (''Scoliodon laticaudus'') is a species of requiem shark in the family Carcharhinidae. It is common in the tropical Indian and western Pacific Oceans, where it forms large schools in shallow water. A small shark reaching a length of , the spadenose shark is named for its distinctively flattened, triangular snout. It is a predator of small bony fishes and invertebrates. This species exhibits the most advanced mode of viviparity of any fish, in which the developed embryos form a highly complex placental connection to the mother at a very small size. Females breed year-round, giving birth to six to 18 pups after a gestation period of 5–6 months. The spadenose shark is harmless to humans and is valued by artisanal and commercial fishers for its meat and fins. Its abundance ensures it forms a significant component of many fisheries in South and Southeast Asia. The International Union for Conservation of Nature has assessed this species as Near threatened. This fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pacific Spadenose Shark
The Pacific spadenose shark (''Scoliodon macrorhynchos'') is a species of requiem shark, in the family Carcharhinidae. It was once regarded as conspecific to the spadenose shark The spadenose shark (''Scoliodon laticaudus'') is a species of requiem shark in the family Carcharhinidae. It is common in the tropical Indian and western Pacific Oceans, where it forms large schools in shallow water. A small shark reaching a le ... (''S. laticaudus'').White, W.T., Last, P.R. & Naylor, G.J.P. (2010''Scoliodon macrorhynchos'' (Bleerer, 1852), a second species of spadenose shark from the western Pacific (Carcharhiniformes: Carcharhinidae) pp. 61–76. In: P.R. Last, W.T. White, J.J. Pogonoski (eds) Descriptions of New Sharks and Rays from Borneo. CSIRO Marine and Atmospheric Research Paper 032, 165 pp. Virology Pacific spadenose sharks are identified as hosts of the ''Flavivirus'' Wenzhou shark flavivirus. While currently unknown if Wenzhou shark flavivirus causes disease in infected shar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Requiem Shark
Requiem sharks are sharks of the family Carcharhinidae in the order Carcharhiniformes. They are migratory, live-bearing sharks of warm seas (sometimes of brackish or fresh water) and include such species as the bull shark, lemon shark, blacktip shark, and whitetip reef shark. Family members have the usual carcharhiniform characteristics. Their eyes are round, and one or two gill slits fall over the pectoral fin base. Most species are viviparous, the young being born fully developed. They vary widely in size, from as small as adult length in the Australian sharpnose shark, up to adult length in the oceanic whitetip shark.Compagno, L.J.VFamily Carcharhinidae - Requiem sharksin Froese, R. and D. Pauly. Editors. 2010FishBase World Wide Web electronic publication, version (10/2013). Scientists assume that the size and shape of their pectoral fins have the right dimensions to minimize transport cost. Requiem sharks tend to live in more tropical areas, but tend to migrate. Fem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Homodont
In anatomy, a heterodont (from Greek, meaning 'different teeth') is an animal which possesses more than a single tooth morphology. Human dentition is heterodont and diphyodont as an example. In vertebrates, heterodont pertains to animals where teeth are differentiated into different forms. For example, members of the Synapsida generally possess incisors, canines ("dogteeth"), premolars, and molars. The presence of heterodont dentition is evidence of some degree of feeding and or hunting specialization in a species. In contrast, homodont or isodont dentition refers to a set of teeth that possess the same tooth morphology. In invertebrates, the term heterodont refers to a condition where teeth of differing sizes occur in the hinge plate, a part of the Bivalvia Bivalvia () or bivalves, in previous centuries referred to as the Lamellibranchiata and Pelecypoda, is a class (biology), class of aquatic animal, aquatic molluscs (marine and freshwater) that have laterally compr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shark Genera
Sharks are a group of elasmobranch cartilaginous fish characterized by a ribless endoskeleton, dermal denticles, five to seven gill slits on each side, and pectoral fins that are not fused to the head. Modern sharks are classified within the division Selachii and are the sister group to the Batomorphi ( rays and skates). Some sources extend the term "shark" as an informal category including extinct members of Chondrichthyes (cartilaginous fish) with a shark-like morphology, such as hybodonts. Shark-like chondrichthyans such as ''Cladoselache'' and ''Doliodus'' first appeared in the Devonian Period (419–359 million years), though some fossilized chondrichthyan-like scales are as old as the Ordovician, Late Ordovician (458–444 million years ago). The earliest confirmed modern sharks (Selachii) are known from the Early Jurassic around , with the oldest known member being ''Agaleus'', though records of true sharks may extend back as far as the Permian. Sharks range in size ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pieter Bleeker
Pieter Bleeker (10 July 1819 – 24 January 1878) was a Dutch medical doctor, Ichthyology, ichthyologist, and Herpetology, herpetologist. He was famous for the ''Atlas Ichthyologique des Indes Orientales Néêrlandaises'', his monumental work on the fishes of East Asia published between 1862 and 1877. Life and work Bleeker was born on 10 July 1819 in Zaandam. He was employed as a medical officer in the Royal Netherlands East Indies Army from 1842 to 1860, (in French). stationed in the Dutch East Indies (now Indonesia). During that time, he did most of his ichthyology work, besides his duties in the army. He acquired many of his specimens from local fishermen, but he also built up an extended network of contacts who would send him specimens from various government outposts throughout the islands. During his time in Indonesia, he collected well over 12,000 specimens, many of which currently reside at the Naturalis Biodiversity Center in Leiden. Bleeker corresponded with Auguste Dumà ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyphyodont
A polyphyodont is any animal whose tooth (animal), teeth are continually replaced. In contrast, diphyodonts are characterized by having only two successive sets of teeth. Polyphyodonts include most toothed fishes (most notably sharks), many reptiles such as crocodiles and geckos, and most other vertebrates, with mammals being the main exception (though Polyphyodont#Evolution in mammals, not absolute). Growth New, permanent teeth grow in the jaws, usually under or just behind the old tooth, from stem cells in the dental lamina. Young animals typically have a full set of teeth when they hatch; there is no tooth change in the egg. Within days, tooth replacement begins, usually in the back of the jaw continuing forward like a wave. On average a tooth is replaced every few months. Crocodilia Crocodilia are the only non-mammalian vertebrates with tooth sockets. Alligators grow a successional tooth (a small replacement tooth) under each mature functional tooth for replacement once a y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exoskeleton
An exoskeleton () . is a skeleton that is on the exterior of an animal in the form of hardened integument, which both supports the body's shape and protects the internal organs, in contrast to an internal endoskeleton (e.g. human skeleton, that of a human) which is enclosed underneath other soft tissues. Some large, hard and non-flexible protective exoskeletons are known as mollusc shell, shell or armour (anatomy), armour. Examples of exoskeletons in animals include the arthropod exoskeleton, cuticle skeletons shared by arthropods (insects, chelicerates, myriapods and crustaceans) and tardigrades, as well as the corallite, skeletal cups formed by hardened secretion of stony corals, the test (biology), test/tunic of sea squirts and sea urchins, and the prominent mollusc shell shared by snails, bivalvia, clams, tusk shells, chitons and nautilus. Some vertebrate animals, such as the turtle, have both an endoskeleton and a turtle shell, protective exoskeleton. Role Exoskeletons c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral
Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and axes. The meaning of terms that are used can change depending on whether a vertebrate is a biped or a quadruped, due to the difference in the neuraxis, or if an invertebrate is a non-bilaterian. A non-bilaterian has no anterior or posterior surface for example but can still have a descriptor used such as proximal or distal in relation to a body part that is nearest to, or furthest from its middle. International organisations have determined vocabularies that are often used as standards for subdisciplines of anatomy. For example, '' Terminolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
