n.
Either of two species of pit viper : the water moccasin or the Mexican moccasin ( Agkistrodon bilineatus ).
The Mexican moccasin, or cantil, is a dangerous snake of lowland regions from the Rio Grande to Nicaragua. About 3 ft (1 m) long, it is brown or black with narrow, irregular, whitish bars on its back and sides. See also copperhead .