Habitat: North-eastern Patagonia and Argentina.
(10) L. xanthogrammus.—Head elongate, snout short; scales in 27 rows, feebly keeled; 196 ventrals; 54 subcaudals.
Colour very dark olive, with a yellow zigzag line on each side from the head to the base of the tail; the angular parts enclose rhombic spaces and lateral triangles; top of head black, with a pair of undulating yellow bands from the nape to the vertex; a bright golden band round the snout; labials bright yellow; ventral shields black, paler in the middle, with yellow triangular spots at their extremities.
Total length, 1,530 millimetres; tail 190.
Habitat: Eastern Ecuador, Andes of Colombia.
(11) L. castelnaudi.—Head narrow and elongate; scales on the head smooth or feebly keeled, small; body-scales strongly keeled, in 25 or 27 rows; 230-253 ventrals; 72-83 subcaudals, all or majority in a single row.
Colour greyish or brown, with dark or light-edged spots or cross-bands; head with dark spots, one of which occupies the middle of the snout; a dark band from the eye to the angle of the mouth; belly brown or blackish, spotted with yellow.
Total length, 1,220 millimetres; tail 180.
Habitat: Brazil, Ecuador, Eastern Peru.
(12) L. nummifer.—Snout broad, rounded; 10 or 11 supralabials; scales in 23-27 rows, strongly keeled; 121-134 ventrals; 26-36 subcaudals, all or the majority single.