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Crotalus Viridis
''Crotalus viridis'' (Common names: prairie rattlesnake, Great Plains rattlesnake, Wright AH, Wright AA. 1957. ''Handbook of Snakes of the United States and Canada''. Ithaca and London: Comstock Publishing Associates. (7th printing, 1985). 1,105 pp. (2 volumes). .) is a venomous pit viper species native to the western United States, southwestern Canada, and northern Mexico. Currently, two subspecies are recognized, including the prairie rattlesnake (''Crotalus viridis viridis''), the nominate subspecies, and the Hopi rattlesnake (''Crotalus viridis nuntius''). Taxonomy The taxonomic history of this species is convoluted. Previously, seven other ''C. viridis'' subspecies were also recognized, including '' C. v. abyssus'', '' C. v. caliginis'', '' C. v. cerberus'', '' C. v. concolor'', '' C. v. helleri'', '' C. v. lutosus'' and '' C. v. oreganus''. However, in 2001 Ashton and de Queiroz described their analysis of the variation of mitochondrial DNA across the range of this species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Constantine Samuel Rafinesque
Constantine Samuel Rafinesque-Schmaltz (; October 22, 1783September 18, 1840) was a French 19th-century polymath born near Constantinople in the Ottoman Empire and self-educated in France. He traveled as a young man in the United States, ultimately settling in Ohio in 1815, where he made notable contributions to botany, zoology, and the study of prehistoric earthworks in North America. He also contributed to the study of ancient Mesoamerican linguistics, in addition to work he had already completed in Europe. Rafinesque was an eccentric and erratic genius. He was an autodidact, who excelled in various fields of knowledge, as a zoologist, botanist, writer and polyglot. He wrote prolifically on such diverse topics as anthropology, biology, geology, and linguistics, but was honored in none of these fields during his lifetime. Indeed, he was an outcast in the American scientific community whose submissions were rejected automatically by leading journals. Among his theories were th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crotalus Oreganus Cerberus
''Crotalus cerberus'' is a venomous pit viper species found in the southwestern United States. It is known as the Arizona black rattlesnake, black rattlesnake, and several other common names. Wright AH, Wright AA. 1957. Handbook of Snakes. 2 volumes. Comstock Publishing Associates. (7th printing, 1985). 1105 pp. . Description According to Wright and Wright (1957), adults grow to an average length of . Klauber (1997) reports the maximum length to be less at , with the smallest gravid female measuring . Klauber LM. 1997. Rattlesnakes: Their Habitats, Life Histories, and Influence on Mankind. Second Edition. 2 volumes. Reprint, University of California Press, Berkeley. . Hubbs and O'Connor (2012) list an adult size range of .Hubbs, Brian and Brendan O'Connor. 2012. '' A Guide to the Rattlesnakes and other Venomous Serpents of the United States''. Tricolor Books. Tempe, Arizona, 129 pp. . (''Crotalus cerberus'', pp. 34-35.) The color pattern consists of a dark grayish, brownish blac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crotalus Viridis - Flickr - Aspidoscelis (15)
''Crotalus'' is a genus of venomous pit vipers in the family Viperidae, known as rattlesnakes or rattlers. Wright AH, Wright AA (1957). ''Handbook of Snakes of the United States and Canada''. Ithaca and London: Comstock Publishing Associates (7th printing, 1985). 1,105 pp. (in 2 volumes). . The genus is found only in the Americas from southern Canada to northern Argentina, and member species are colloquially known as rattlesnakes. The generic name ''Crotalus'' is derived from the Greek word ''krótalοn'', which means "rattle" or "castanet", and refers to the rattle on the end of the tail, which makes this group (genera ''Crotalus'' and ''Sistrurus'') so distinctive.Campbell JA, Lamar WW (2004). ''The Venomous Reptiles of the Western Hemisphere''. Ithaca and London: Comstock Publishing Associates. 870 pp. 1,500 plates. . Currently, 32 to 45 species are recognized as being valid. Description Members of the genus ''Crotalus'' range in size from only ('' C. intermedius'', '' C. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Robert C
The name Robert is an ancient Germanic given name, from Proto-Germanic "fame" and "bright" (''Hrōþiberhtaz''). Compare Old Dutch ''Robrecht'' and Old High German ''Hrodebert'' (a compound of '' Hruod'' ( non, Hróðr) "fame, glory, honour, praise, renown" and ''berht'' "bright, light, shining"). It is the second most frequently used given name of ancient Germanic origin. It is also in use as a surname. Another commonly used form of the name is Rupert. After becoming widely used in Continental Europe it entered England in its Old French form ''Robert'', where an Old English cognate form (''Hrēodbēorht'', ''Hrodberht'', ''Hrēodbēorð'', ''Hrœdbœrð'', ''Hrœdberð'', ''Hrōðberχtŕ'') had existed before the Norman Conquest. The feminine version is Roberta. The Italian, Portuguese, and Spanish form is Roberto. Robert is also a common name in many Germanic languages, including English, German, Dutch, Norwegian, Swedish, Scots, Danish, and Icelandic. It can be use ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internasal Scales
In snakes, the internasal scales are those on top of the head between the scales that surround the nostrils. Wright AH, Wright AA (1957). ''Handbook of Snakes of the United States and Canada''. Ithaca and London: Comstock Publishing Associates. (7th printing, 1985). 1,105 pp. (in two volumes). . They are usually paired and situated just behind the rostral.U.S. Navy (1991). ''Poisonous Snakes of the World''. United States Government. New York: Dover Publications Inc. 203 pp. . Related scales *Nasal scales *Rostral scale See also *Snake scales *Scale (zoology) In most biological nomenclature, a scale ( grc, λεπίς, lepís; la, squāma) is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran (butterfly and moth) species, scales are plates on the surface ... References Snake scales {{snake-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crotalus Viridis
''Crotalus viridis'' (Common names: prairie rattlesnake, Great Plains rattlesnake, Wright AH, Wright AA. 1957. ''Handbook of Snakes of the United States and Canada''. Ithaca and London: Comstock Publishing Associates. (7th printing, 1985). 1,105 pp. (2 volumes). .) is a venomous pit viper species native to the western United States, southwestern Canada, and northern Mexico. Currently, two subspecies are recognized, including the prairie rattlesnake (''Crotalus viridis viridis''), the nominate subspecies, and the Hopi rattlesnake (''Crotalus viridis nuntius''). Taxonomy The taxonomic history of this species is convoluted. Previously, seven other ''C. viridis'' subspecies were also recognized, including '' C. v. abyssus'', '' C. v. caliginis'', '' C. v. cerberus'', '' C. v. concolor'', '' C. v. helleri'', '' C. v. lutosus'' and '' C. v. oreganus''. However, in 2001 Ashton and de Queiroz described their analysis of the variation of mitochondrial DNA across the range of this species ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wolfgang Wüster
Wolfgang Wüster (born 1964) is a herpetologist and Reader in zoology at Bangor University, UK. Wüster attained his bachelor's degree at the University of Cambridge in 1985 and his doctorate at the University of Aberdeen in 1990. His primary areas of research are the systematics and ecology of venomous snakes and the evolution of their venoms. He has authored approximately 150 scientific papers on varying herpetological subjects. Recent contributions have included descriptions of new species, especially of cobras, several studies into how natural selection drives the evolution of snake venoms, and demonstrating the likely vulnerability of Madagascar's native fauna to the skin toxins of the invasive Asian toad ''Duttaphrynus melanostictus''. He was the scientific editor for ''The Herpetological Journal'' (2002–2009), the scientific publication of the British Herpetological Society. He has participated in the description of the following taxa: * ''Naja mandalayensis'' Slowins ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crotalus Cerberus
''Crotalus cerberus'' is a venomous pit viper species found in the southwestern United States. It is known as the Arizona black rattlesnake, black rattlesnake, and several other common names. Wright AH, Wright AA. 1957. Handbook of Snakes. 2 volumes. Comstock Publishing Associates. (7th printing, 1985). 1105 pp. . Description According to Wright and Wright (1957), adults grow to an average length of . Klauber (1997) reports the maximum length to be less at , with the smallest gravid female measuring . Klauber LM. 1997. Rattlesnakes: Their Habitats, Life Histories, and Influence on Mankind. Second Edition. 2 volumes. Reprint, University of California Press, Berkeley. . Hubbs and O'Connor (2012) list an adult size range of .Hubbs, Brian and Brendan O'Connor. 2012. '' A Guide to the Rattlesnakes and other Venomous Serpents of the United States''. Tricolor Books. Tempe, Arizona, 129 pp. . (''Crotalus cerberus'', pp. 34-35.) The color pattern consists of a dark grayish, brownish black ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Systematics
Biological systematics is the study of the diversification of living forms, both past and present, and the relationships among living things through time. Relationships are visualized as evolutionary trees (synonyms: cladograms, phylogenetic trees, phylogenies). Phylogenies have two components: branching order (showing group relationships) and branch length (showing amount of evolution). Phylogenetic trees of species and higher taxa are used to study the evolution of traits (e.g., anatomical or molecular characteristics) and the distribution of organisms (biogeography). Systematics, in other words, is used to understand the evolutionary history of life on Earth. The word systematics is derived from the Latin word '' systema,'' which means systematic arrangement of organisms. Carl Linnaeus used 'Systema Naturae' as the title of his book. Branches and applications In the study of biological systematics, researchers use the different branches to further understand the relationshi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, the equivalent Latin term ''cladus'' (plural ''cladi'') is often used in taxonomical literature. The common ancestor may be an individual, a population, or a species (extinct or 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 taxa that are not clades; that is, taxa that are not monophyletic. Some of the relationships between organisms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitochondrial DNA
Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial DNA is only a small portion of the DNA in a eukaryotic cell; most of the DNA can be found in the cell nucleus and, in plants and algae, also in plastids such as chloroplasts. Human mitochondrial DNA was the first significant part of the human genome to be sequenced. This sequencing revealed that the human mtDNA includes 16,569 base pairs and encodes 13 proteins. Since animal mtDNA evolves faster than nuclear genetic markers, it represents a mainstay of phylogenetics and evolutionary biology. It also permits an examination of the relatedness of populations, and so has become important in anthropology and biogeography. Origin Nuclear and mitochondrial DNA are thought to be of separate evolutionary origin, with the mtDNA being derived ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crotalus Oreganus
''Crotalus oreganus'', commonly known as the (northern) Pacific rattlesnake, Wright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates. (7th printing, 1985). 1105 pp. . is a venomous pit viper species found in western North America from the Baja California Peninsula to the southern interior of British Columbia. Description The size of this species varies greatly, with some populations being stunted and others growing very large. Mainland specimens often reach in length, with the largest on record being (Klauber, 1956)Campbell JA, Lamar WW. 2004. The Venomous Reptiles of the Western Hemisphere. Comstock Publishing Associates, Ithaca and London. 870 pp. 1500 plates. . for ''C. o. oreganus''. Klauber LM. 1997. Rattlesnakes: Their Habitats, Life Histories, and Influence on Mankind. Second Edition. First published in 1956, 1972. University of California Press, Berkeley. . This species, in its various forms, shows considerable ontogenetic variation. Juveniles u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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