#viper  venomous Old World snakes characterized by hollow venom-conducting fangs in the upper jaw
  supertype:  #ophidian__snake__serpent  limbless scaly elongate reptile; some are venomous
  member of:  #family_Viperidae
  subtype:  #common_viper__adder__Vipera_berus  small terrestrial viper common in northern Eurasia
  subtype:  #asp_viper__aspviper__asp__Vipera_aspis  of southern Europe; similar to but smaller than the adder
  subtype:  #puff_adder__Bitis_arietans  large African viper that inflates its body when alarmed
  subtype:  #gaboon_viper__Bitis_gabonica  large heavy-bodied brilliantly marked and extremely venomous west African viper
  subtype:  #horned_viper__cerastes__sand_viper__horned_asp__Cerastes_cornutus  highly venomous viper of North Africa and southwest Asia having a horny spine above each eye
  subtype:  #pit_viper__pitviper  New World vipers with hollow fangs and a heat-sensitive pit on each side of the head
     subtype:  #copperhead__Agkistrodon_contortrix  common coppery brown pit viper of upland eastern United States
     subtype:  #cottonmouth__water_moccasin__watermoccasin__cottonmouth_moccasin__cottonmouthmoccasin__agkistrodonpiscivoru  venomous semiaquatic snake of swamps in southern United States
     subtype:  #rattlesnake  pit viper with horny segments at the end of the tail that rattle when shaken
        subtype:  #diamondback_rattlesnake__diamondbackrattlesnake__diamondback__crotalusadamanteu  large deadly rattlesnake with diamond-shaped markings
        subtype:  #timber_rattlesnake__banded_rattlesnake__Crotalus_horridus_horridus  widely distributed in rugged ground of eastern United States
           subtype:  #canebrake_rattlesnake__canebrakerattlesnake__canebrake_rattler__canebrakerattler__Crotalus_horridus_atricaudatus  southern variety
        subtype:  #prairie_rattlesnake__prairie_rattler__Western_rattlesnake__Crotalus_viridis  widely distributed between the Mississippi and the Rockies
        subtype:  #horned_rattlesnake__sidewinder__Crotalus_cerastes  small pale-colored desert rattlesnake of southwestern United States; body moves in an S-shaped curve
        subtype:  #Western_diamondback_rattlesnake__Western_diamondback__Crotalus_atrox  largest and most dangerous North American snake; of southwestern United States and Mexico
        subtype:  #rock_rattlesnake__Crotalus_lepidus  mountain rock dweller of Mexico and most southern parts of United States southwest
        subtype:  #tiger_rattlesnake__tigerrattlesnake__Crotalus_tigris  having irregularly cross-banded back; of arid foothills and canyons of southern Arizona and Mexico
        subtype:  #Mojave_rattlesnake__Crotalus_scutulatus  extremely dangerous; most common in areas of scattered scrubby growth; from Mojave Desert to w. Texas and into Mexico
        subtype:  #speckled_rattlesnake__Crotalus_mitchellii  markings vary but usually harmonize with background; of sw Arizona and Baja California
        subtype:  #massasauga_rattler__massasauga__Sistrurus_catenatus  pygmy rattlesnake found in moist areas from the Great Lakes to Mexico; feeds on mice and small amphibians
        subtype:  #ground_rattler__massasauga__Sistrurus_miliaris  small pygmy rattlesnake
     subtype:  #fer-de-lance__Bothrops_atrops  large extremely venomous pit viper of Central and South America

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