275 

 SI BON 



Sibon dim! diata dimjdiata (Ciinther) 



1884 Petaloqnathus mult i fasciatus Jan, in Bocourt, Bull. Soc. Philom. Paris, (7) 8: 182. Type- 

 locality: Verapaz, Guatemala. 

 1*^60 Sibon dimjdiata dimjdiata — Peters, Misc. Publ. Mus. Zool. Univ. Mich., 114: 182, pi. 7b. 



Distribution! Atlantic coast of central America from Veracruz to Nicaragua, excluding the 

 Yucatan Peninsula. 



S j bon dimjdiata qrandocul i s (Mullen) 



I85O Leptoqnathus ( Asthenoqna thus ) qrandocul is Miiller, Verh. Nat. Ges. Basel, 8: 27I. Type- 

 locality: Mazatenango, Guatemala. 

 I960 Sibon dimjdiata qrandoculis — Peters, Misc. Publ. Mus. Zool. Univ. Mich., 114: 185, pi. 7a. 



Distribution: Pacific slope of Guatemala. 



SIBON DUNN I Peters 

 nebulata group 



1957 Sibon dunni Peters. Copeia, 1557= ll'^- Type-locality: Pimanpjro, San Nicholas, Imbabura 



Province, Ecuador. 

 1960 Sibon dunnj — Peters, Misc. Publ. Mus. Zool. Univ. Mich., 114: I56, pi. 7d. 



Distribution: Known only from type locality. 



SIBON LONGIFRENIS (Stejneger) 

 arqus group 



1909 Mesopelt is lonqif renis Stejneger, Proc. U. S. Nat. Mus., JS: 457- Type-locality: Bocas del 



Toro, Panama. 

 1951 Dipsas costaricensis Taylor, Univ. Kansas Sc i . Bull., "^i: 63. Type-locality: 5 '"' southwest 



of Turrialba, Morehead Finca, Costa Rica. 

 1960 Sibon lonqifrenis — Peters, Misc. Publ. Mus. Zool. Univ. Mich., 114: 192. 



Distribution: Atlantic slopes of Panama (a single locality) and Costa Rica (two localities). 



SIBON NEBULATA (Linnaeus) 

 nebulata group 



1758 Coluber nebulatus Linnaeus. Syst. Nat., Ed. 10: 222. Type-locality: America. 

 1826 Si bon nebula tu& — Fitzinger, Neue Glassif. Rept.! 31' 



Distribution: Southeastern Mexico, Central America and northern South America. 



Content: Four subspecies. 



Key to the subspecies Clave de subespecies 



1. First dorsal blotches not different from 1. Primerai manchas dorsales no diferentes 



rest of body blotches 2 del resto de manchas del cuerpo 2 



First dorsal blotches wide, well-marked Primeras manchas dorsales anchas, b i en 



hartweq i marcadas hartweq i 



2. Dorsal pattern often obscured by heavy 2. Dise^o dorsal f recuentemente oscurecido por 



deposition of black pigment, belly heavily mayor deposito de pigmento negro, vientre 



spotted with dark brown, or may be com- densamente manchado de pardo oscuro, 



pletely black 3 pudiendo ser completamente negro 3 



Dorsal pattern of chocolate or reddish- DiseTIo dorsal con manchas de color choco- 

 brown blotches, contrasting strongly with late pardo rojizo que contraste fuerte- 

 light-brown or grayish interblotch areas — mente con los interespac ios grises 

 nebulata pardo claros nebulata 



