276 



SIBON 



3. Ventrals fewer than I75 in both sexes; sub- 3. Ventrales menos de 175 e" ambos sexos; sub- 



caudals fewer than 85 in males, fewer than caudales menos de 85 en machos, y de 75 e" 



75 in females popayanens is hembras popayanens is 



Ventrals more than I75 In both sexes; sub- Ventrales mas de 175 e" ambos sexos; sub- 



caudals more than 5O in males, more than caudales mas de ^0 en machos, mas de 80 en 



80 in females leucomelas hembras leucomelas 



Sibon nebulata nebulata (Linnaeus) 



I7S8 Coluber sibon Linnaeus. Systema Naturae, Ed. 10: 222. Type-locality; Africa. 



184S Coluber varieqatus Hallowell. Proc. Acad. Nat. Sc i . Phila., 1845: 244. Type-locality: 



within 200 mi of Caracas, Venezuela. 

 1879 Leptoanathus affinis Fischer, Verh. Naturwiss. Ver. Hamburg, (2) 3: 78, pi. 1, figs. la-c. 



Type-locality: Sabanna Larga, Colombia. 

 1960 Sibon nebulata nebulata — Peters. Misc. Publ. Mus. Zool. Univ. Mich., 114: 199. 



Distribution: Nayarit on west and Veracruz on east in Mexico, through lowlands of Central 



America, including Yucatan Peninsula, to extreme northern South America east and north 



of Andean Chain; Trinidad and Tobago Islands; an isolated population in northwestern 

 Ecuador below range of ^. n. leucomelas . 



Sibon nebulata hartweq i Peters 



1960 Sibon nebulata hartweq i Peters. Misc. Publ. Mus. Zool. Univ. Mich., 114: 200, pi. 8, figs, 

 d-e. Type-locality; Barrancaberme ja, Provincia Santander, Colombia. 



Distribution: Upper reaches of R'o Magdalena and tributaries, valley of R'o Porce (Medell'n), 

 Colomb ia. 



S ibon nebulata leucomelas (Boulenger) 



1896 Leptoqnathus leucomelas Boulenger, Ann. Mag. Nat. Hist., (6) I7; 18. Type-locality: 



Buenaventura, Colombia. 

 1960 Sibon nebulata leucomelas — Peters. Misc. Publ. Mus. Zool. Univ. Mich., 114: 202, pi. 8, 



fig. c. 



Distribution: Panama-Colombia border, including all coastal Colombia to northwestern Ecuador. 



S ibon nebulata popayanens is Peters 



i960 S i bon nebulata popayanens is Peters, Misc. Publ. Mus. Zool. Univ. Mich., 114: 203, Pl* ^i 

 figs. a-b. Type-locality; Popayan, Provincia Cauca, Colombia. 



Distribution: Upper reaches of R'o Cauca, Colombia. 



SIBON SANNIOLA (Cope) 

 annulata group 



1866 Mesopeltis sanniolus Cope. Proc. Acad. Nat, Sc i . Phila., 1866: 3I8. Type-locality; Yucatan, 

 Mexico; restricted to Chichen I tza, Yucatan, by Smith and Taylor, Univ. Kansas Sci. Bull., 



33, 1950, 352. 



1949 Sibon sanniolus — Smith. Proc. U. S. Nat. Mus., 93; 47O. 



1960 Sibon sanniola — Peters. Misc. Publ. Mus. Zool. Univ. Mich., 114: I87. 



Distribution: Northern and eastern parts of Yucatan Peninsula; British Honduras. 



