Assertion: pit viper | /r/HasProperty | group
Facets:
Source sentences:
text: Rattlesnakes are pit vipers (subfamily Crotalinae of the family Viperidae), a group named for the small heat-sensing pit between each eye and nostril that aids in hunting.
text: In fact, it has the least potent venom of any pit vipers (a group that includes cottonmouths and rattlesnakes).