About Bothrops ammodytoides Leybold, 1873
This species, Bothrops ammodytoides, has a stocky build. It reaches an average total length of 45–75 cm (18–30 inches), and can grow to almost 1 m (39 inches) in total length. Its rostral scale is elongated vertically, and its snout is upturned, a feature similar to that of hog-nosed pitvipers of the genus Porthidium. Dorsally, the body is pale brown, marked with a series of large, squarish dark brown spots or crossbars that are edged in black. In some individuals, these markings alternate to form a zigzag stripe. A dark streak runs behind the eye. Ventrally, the body is yellowish with scattered brown dots. The dorsal scales are very strongly keeled, arranged in 23 or 25 rows at midbody. It has 149–160 ventrals, an entire anal plate, and 30–38 divided subcaudals. The dorsal surface of the head is covered in small, imbricate, keeled scales. The large supraocular scales are separated by 8 or 9 rows of these small scales. Two rows of scales separate the eye from the upper labials. There are 9 or 10 upper labials; the second upper labial is separated from the loreal pit, and the third and fourth upper labials are the largest. The temporal scales are keeled. This species is found only in Argentina, in the provinces of Buenos Aires, Catamarca, Córdoba, Chubut, La Pampa, La Rioja, Mendoza, Neuquén, Río Negro, San Juan, San Luis, Santa Cruz, and Tucumán. Its vertical distribution ranges from sea level to at least 2,000 m (6,600 ft) in altitude. The type locality was first recorded as "northern Argentina", and later emended to "province of Mendoza" by Campbell and Lamar (1989). The geographic range of Bothrops ammodytoides extends to 47° S Latitude, which may make it the world's southernmost snake. It prefers dry regions, and occurs in temperate to subtropical savannas and steppes. It is found mostly in sandy, rocky areas, including coastal dunes, steep riverbanks, and salt flats. Near the upper limits of its altitude range, it can occasionally be found in broadleaf evergreen forest. The venom of Bothrops ammodytoides is potentially lethal to humans, causing internal bleeding and tissue damage around the bite wound. These snakes are defensive of their territory and become aggressive when disturbed.
