|
Agkistrodon Howardgloydi
''Agkistrodon howardgloydi'' is a species of venomous snake, a pit viper (Crotalinae), that is endemic to Central America. It is most commonly called castellana,Conant, R. 1984. ''A new subspecies of the pit viper Agkistrodon bilineatus (Reptilia: Viperidae) from Central America.'' Proceedings of the Biological Society of Washington. 97: 135-141.Gloyd, H. K., and R. Conant. 1990. ''Snakes of the Agkistrodon Complex: A Monographic Review.'' Society for the Study of Amphibians and Reptiles, Contributions in Herpetology, Number 6. Ithaca, New York, USA. Savage, J. M. 2002. ''The Amphibians and Reptiles of Costa Rica, A Herpetofauna between Two Continents, between Two Seas.'' University of Chicago Press, Chicago, Illinois. xx, 934 pp. but it has also been called the southern cantil,Porras, L.W., L. D. Wilson, G. W. Schuett, R. S. Reiserer. 2013. ''A taxonomic reevaluation and conservation assessment of the common cantil, Agkistrodon bilineatus (Squamata: Viperidae): a race against time ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Roger Conant (herpetologist)
Roger Conant (May 6, 1909 – December 19, 2003) was an American herpetologist, author, educator and conservationist. He was Director Emeritus of the Philadelphia Zoo and adjunct professor at the University of New Mexico. He wrote one of the first comprehensive field guides for North American reptiles in 1958 entitled: ''A Field Guide to Reptiles and Amphibians of Eastern and Central North America'', in the Peterson Field Guide series. Biography Born in Mamaroneck, New York, Conant lost his father when he was young. When he was a teenager he took a job at a local zoo to help his mother make ends meet, which, along with participating in the Boy Scouts of America, began his lifelong passion for reptiles. He was the first Eagle Scout in Monmouth County Council, New Jersey in 1924. He moved to Toledo, Ohio in 1929 and worked as Curator of Reptiles, and later General Curator at the Toledo Zoo from 1929 to 1935. In 1935 he returned to Philadelphia and became the Curator of Reptiles at th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agkistrodon Laticinctus
''Agkistrodon laticinctus'', commonly known as the broad-banded copperhead, is a venomous pit viper species,Frank T. Burbrink, Timothy J. Guiher (2014). Considering gene flow when using coalescent methods to delimit lineages of North American pitvipers of the genus Agkistrodon. Zoological Journal of the Linnean Society, December 2014. formerly considered a subspecies of Agkistrodon contortrix, which is found in the southern United States, from Kansas, through Oklahoma and throughout central Texas. Description This form is typically a light tan in color, with darker brown, wide crossbands - which gives it its common name. The actual color varies, by locality, from a red-brown, to a gray-brown. It overlaps with the southern copperhead, '' A. contortrix'' in the eastern reaches of its range, making specimens there difficult to distinguish, but generally ''A. contortrix'' has banding that narrows at the spine, creating hourglass shapes, whereas ''A. laticinctus'' has bands that do ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supralabial Scale
In reptiles, the supralabial scales, also called upper-labials, are those scales that border the mouth opening along the upper jaw. They do not include the median scaleWright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates (7th printing, 1985). 1105 pp. . (rostral scale). The term ''labial'' originates from ''Labium'' (Latin for "lip"), which refers to any lip-like structure. The numbers of these scales present, and sometimes the shapes and sizes, are some of many characteristics used to differentiate species from one another. Related scales * Sublabial scales * Rostral scale * Mental scale See also * Labial scales * Snake scales * Anatomical terms of location Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ... References {{Reflist Snake scales ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Supraocular Scale
In scaled reptiles, supraocular scales are (enlarged) scales on the crown immediately above the eye.Mallow D, Ludwig D, Nilson G. 2003. True Vipers: Natural History and Toxinology of Old World Vipers. Malabar, Florida: Krieger Publishing Company. 359 pp. . The size and shape of these scales are among the many characteristics used to differentiate species from each another. In many species of boids and viperids, the supraoculars are heavily fragmented. In others, such as the colubrids and elapids, they are enlarged. See also * Ocular scales * Snake scales * Anatomical terms of location Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position pro ... References {{Reflist Snake scales ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Melanism
The term melanism refers to black pigment and is derived from the gr, μελανός. Melanism is the increased development of the dark-colored pigment melanin in the skin or hair. Pseudomelanism, also called abundism, is another variant of pigmentation, identifiable by dark spots or enlarged stripes, which cover a large part of the body of the animal, making it appear melanistic. The morbid deposition of black matter, often of a malignant character causing pigmented tumors, is called melanosis. Adaptation Melanism related to the process of adaptation is called adaptive. Most commonly, dark individuals become Fitness (biology), fitter to survive and reproduce in their environment as they are better camouflaged. This makes some species less conspicuous to predators, while others, such as leopards, use it as a foraging advantage during night hunting. Typically, adaptive melanism is Heritability, heritable: A Dominance (genetics), dominant allele, which is entirely or nearly ent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Subcaudal Scales
In snakes, the subcaudal scales are the enlarged plates on the underside of the tail.Wright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates (7th printing, 1985). 1105 pp. . These scales may be either single or divided (paired) and are preceded by the anal scale. Related scales * Anal scale * Ventral scales See also * Snake scales Snakes are elongated, limbless, carnivorous reptiles of the suborder Serpentes . Like all other squamates, snakes are ectothermic, amniote vertebrates covered in overlapping scales. Many species of snakes have skulls with several more joints ... References {{Reflist Snake scales ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ventral Scales
In snakes, the ventral scales or gastrosteges are the enlarged and transversely elongated scales that extend down the underside of the body from the neck to the anal scale. When counting them, the first is the anteriormost ventral scale that contacts the paraventral (lowermost) row of dorsal scales on either side. The anal scale is not counted.Campbell JA, Lamar WW. 2004. The Venomous Reptiles of the Western Hemisphere. 2 volumes. Comstock Publishing Associates, Ithaca and London. 870 pp. 1500 plates. . Related scales * Preventral scales * Anal scale * Subcaudal scales * Paraventral scales See also * Snake scale Snakes, like other reptiles, have skin covered in scale (zoology), scales.Boulenger, George A. 1890 The Fauna of British India. p. 1 Snakes are entirely covered with scales or scutes of various shapes and sizes, known as snakeskin as a whole. A ... References {{Reflist Snake scales ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Scales
In snakes, the dorsal scales are the longitudinal series of plates that encircle the body, but do not include the ventral scales. Campbell JA, Lamar WW (2004). ''The Venomous Reptiles of the Western Hemisphere''. Ithaca and London: Comstock Publishing Associates. 2 volumes. 870 pp. 1,500 plates. . When counting dorsal scales, numbers are often given for three points along the body, for example 19:21:17. These numbers correspond to the number of dorsal scales around the body at a head's length behind the head, at midbody and at a head's length before the vent. If only one number is given, it is for the midbody count. Dorsal scale are easiest to count diagonally, starting with the paraventral scale row. In doing so, it is often noted that certain scale rows are raised, keeled or smooth as opposed to the others.U.S. Navy (1991). ''Poisonous Snakes of the World''. United States Government. New York: Dover Publications Inc. 203 pp. . See also *Snake scales *Anatomical terms of locat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Keeled Scales
Keeled scales refer to reptile scales that, rather than being smooth, have a ridge down the center that may or may not extend to the tip of the scale, Campbell, J. A., Lamar, W. W. (2004). ''The Venomous Reptiles of the Western Hemisphere''. Ithaca and London: Comstock Publishing Associates. 870 pp. 1,500 plates. . making them rough to the touch. According to Street's (1979) description of European lizards and snakes, in those that have keeled scales the keels are usually stronger in male specimens and are consistently arranged according to the species of reptiles, even though many others do not have them. With European lizards, the dorsal scales are usually well keeled, while those on the flanks are more weakly keeled and those on the belly smooth. Street, D. (1979). ''The Reptiles of Northern and Central Europe''. London: B.T. Batsford Ltd. 268 pp. . Non-European lizards such as ''Sphaerodactylus macrolepis'' also display keeled scales. Klauber (1997), describes how the keels on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biogeography
Biogeography is the study of the distribution of species and ecosystems in geographic space and through geological time. Organisms and biological communities often vary in a regular fashion along geographic gradients of latitude, elevation, isolation and habitat area.Brown University, "Biogeography." Accessed February 24, 2014. . Phytogeography is the branch of biogeography that studies the distribution of plants. Zoogeography is the branch that studies distribution of animals. Mycogeography is the branch that studies distribution of fungi, such as mushrooms. Knowledge of spatial variation in the numbers and types of organisms is as vital to us today as it was to our early human ancestors, as we adapt to heterogeneous but geographically predictable environments. Biogeography is an integrative field of inquiry that unites concepts and information from ecology, evolutionary biology, taxonomy, geology, physical geography, palaeontology, and climatology.Dansereau, Pierre. 1957 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sister Taxa
In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and taxon B are sister groups to each other. Taxa A and B, together with any other extant or extinct descendants of their most recent common ancestor (MRCA), form a monophyletic group, the clade AB. Clade AB and taxon C are also sister groups. Taxa A, B, and C, together with all other descendants of their MRCA form the clade ABC. The whole clade ABC is itself a subtree of a larger tree which offers yet more sister group relationships, both among the leaves and among larger, more deeply rooted clades. The tree structure shown connects through its root to the rest of the universal tree of life. In cladistic standards, taxa A, B, and C may represent specimens, species, genera, or any other taxonomic units. If A and B are at the same taxonomic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Agkistrodon Russeolus
''Agkistrodon russeolus'', commonly called the Yucatecan cantil, Gloyd HK, Conant R (1990). ''Snakes of the ''Agkistrodon'' Complex: A Monographic Review''. Society for the Study of Amphibians and Reptiles. 614 pp., 52 plates. LCCN 89-50342. . is a venomous pit viper species endemic to the Yucatán Peninsula in Mexico and northern Belize. Description Adults of ''A. russeolus'' may grow to a total length (including tail) of more than . Gloyd and Conant (1990) reported that the largest specimens they saw were from Pisté, Yucatán: a male of with a missing tail tip and a female of . The average tail length is 19.2% of total body length in males and 16% in females. Scalation includes 23 rows of keeled dorsal scales at midbody; 131-141 ventral scales; and 46-62 subcaudal scales, most of which are paired, especially towards the tail tip. The dorsal color pattern consists of light brown to deep reddish brown ground color overlaid with 12-18 broad brown or brownish crossbands. La ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.jpg "Click for more on -> Agkistrodon Howardgloydi")
.JPG "Click for more on -> Agkistrodon Laticinctus")
.png "Click for more on -> Sister Taxa")