Heterodon 4280536 219414201 2008-06-15T02:59:16Z Mczech1111 2140449 /* Behavior */ {{Taxobox | name = ''Heterodon'' | image = Heterodon_platyrhinos.jpg | image_caption = Eastern hog-nosed snake, ''[[Heterodon platirhinos|H. platirhinos]]'' | regnum = [[Animal]]ia | phylum = [[Chordate|Chordata]] | subphylum = [[Vertebrate|Vertebrata]] | classis = [[Reptile|Reptilia]] | ordo = [[Squamata]] | subordo = [[Serpentes]] | familia = [[Colubrid]]ae | subfamilia = [[Xenodontinae]] | genus = '''''Heterodon''''' | genus_authority = [[Pierre André Latreille|Latreille]] ''In'' [[Charles-Nicolas-Sigisbert Sonnini de Manoncourt|Sonnini]] & Latreille, 1801 | synonyms = * ''Boa'' * ''Coluber'' * ''Natrix'' * ''Oxyrhina'' * ''Pelias'' * ''Scytale'' * ''Scytalus'' * ''Vipera''<ref name="W&W57">Wright AH, Wright AA. 1957. Handbook of Snakes. Comstock Publishing Associates. (7th printing, 1985). 1105 pp. ISBN 0-8014-0463-0.</ref> }} :'''''Common names:''' hog-nosed snakes,<ref name="W&W57"/> North American hog-nosed snakes.<ref name="ITIS">{{ITIS|ID=174153|taxon=Heterodon|year=2006|date=30 November}}</ref>'' '''''Heterodon''''' is a [[genus]] of [[colubrid]]s found in [[North America]]. Snakes in this genus are stout with upturned snouts, and are perhaps best known for their characteristic threat displays. Three [[species]] are currently recognized.<ref name="ITIS"/> ==Description== [[Image:Heterodon_nasicus.jpg|left|thumb|Western hog-nosed snake, ''[[Heterodon nasicus|H. nasicus]]'']] Adults grow to 30-120 cm in length. The body is stout and the head is slightly distinct from the neck. The latter is expandable, the anterior ribs being capable of spreading to flatten that portion of the body, similar to a [[Naja|cobra]]. The tail is short and the [[anal scale]] divided. The [[dorsal scales]] are keeled with apical pits in 23-25 rows. The [[rostral scale]] is projecting, upturned, recurved and keeled dorsally. There are usually 1-20 accessory scales (azygous) that separate the [[internasals]] and the [[prefrontals]]. A subocular ring is present with 8-12 [[ocular scales]]. There are 7-8 [[upper labials]] and 9-13 [[lower labials]]. The [[ventrals]] number 114-152 and the [[subcaudals]] 27-60.<ref name="W&W57"/> The color pattern is extremely variable. ''[[Heterodon nasicus|H. nasicus]]'' tends to be sandy colored with black and white markings, while ''[[Heterodon platirhinos|H. platirhinos]]'' varies from [[red]]s, [[green]]s, [[Orange (color)|orange]]s, [[brown]]s, to [[black]] depending on locality. They are sometimes blotched and sometimes solid-colored. Members of this genus are considered to be [[rear-fanged]] and [[venom (poison)|venomous]], but the venom they excrete is not deadly to humans.<ref name="">[http://www.hognose.com/pages/venomous.htm Are Hognosed Snakes Venomous?] at [http://www.hognose.com/ Hognose.com]. Accessed [[1 December]] [[2006]].</ref> ==Behavior== When threatened, the hognose snake will flatten its neck and raise its head off the ground, similar to a [[cobra]], and hiss. It may sometimes feign strikes, but is not apt to bite. This behavior has earned the hognose several nicknames, such as "blowing adder," "flathead," "spreading adder," or "hissing adder." If this threat display does not work to deter a would-be predator, the hognose snake will often roll onto its back and play dead with its [[mouth]] open and [[tongue]] lolling, going as far as to emit a foul musk from the [[cloaca]]. If the snake is rolled upright while in this state, it will often roll over again as if to insist that it is really dead. Hognose snakes' most distinguishing characteristic is their upturned snout, which is believed to aid in digging in sandy soils. ==Feeding== The bulk of ''Heterodon'' diet is made up of [[rodent]]s, and [[lizard]]s. ''H. platirhinos '' is an exception, and specializes in feeding on [[toad]]s, having an immunity to the toxins toads secrete. ==Captivity== Hognose snakes are frequently found in the exotic pet trade. ''H. nasicus'' are often considered to be the easiest to care for, and captive bred stock is easily found. ''H. platirhinos '' is commonly found, but their dietary requirements can be a challenge for some keepers. ==Species== {|cellspacing=0 cellpadding=2 border=1 style="border-collapse: collapse;" !bgcolor="#f0f0f0"|Species<ref name="ITIS"/> !bgcolor="#f0f0f0"|Authority<ref name="ITIS"/> !bgcolor="#f0f0f0"|Subsp.*<ref name="ITIS"/> !bgcolor="#f0f0f0"|Common name<ref name="ITIS"/> !bgcolor="#f0f0f0"|Geographic range<ref name="B&K79">Behler JL, King FW. 1979. The Audubon Society Field Guide to North American Reptiles and Amphibians. New York: Alfred A. Knopf. 743 pp. LCCCN 79-2217. ISBN 0-394-50824-6.</ref> |- |''[[Heterodon nasicus|H. nasicus]]'' |[[Spencer Fullerton Baird|Baird]] & [[Charles Frédéric Girard|Girard]], 1852 |align="center"|2 |Western hog-nosed snake |style="width:40%"|Southeastern [[Alberta]] and northwestern [[Manitoba]] in [[Canada]], south to southeastern [[Arizona]] and [[Texas]] in the [[United States]] and into northern [[Mexico]]. Disjunct populations in [[Minnesota]], [[Iowa]], [[Illinois]], [[Missouri]] and [[Arkansas]]. |- |''[[Heterodon platirhinos|H. platirhinos]]'' |[[Pierre André Latreille|Latreille]], 1801 |align="center"|0 |Eastern hog-nosed snake |United States: eastern-central Minnesota to extreme southern [[New Hampshire]], south to southern [[Florida]] and west to eastern Texas and western [[Kansas]]. |- |''[[Heterodon simus|H. simus]]'' |([[Carolus Linnaeus|Linnaeus]], 1766) |align="center"|0 |Southern hog-nosed snake |United States: from the coastal plain in southeast [[North Carolina]], south to [[Lake Okeechobee]] in Florida and west to southeastern [[Mississippi]]. |- |} ''*) Not including the nominate subspecies (typical form).'' ==References== {{reflist}} == External links == {{Commonscat|Heterodon}} * {{NRDB genus|genus=Heterodon|date=14 September|year=2007}} [[Category:Colubrids]] [[ja:シシバナヘビ属]] [[zh:豬鼻蛇屬]]