By locality:Boa c. constrictor
Distribution area: From northern part of South America to middle of the continent. The eastern border of distribution area is the costal region of Atlantic Ocean. In the West, mountainous Andes separates this subspecies from the others.
Distribution countries: Colombia, Venezuela, Trinidad and Tobago, Guyana, Suriname, French Guyana, Ecuador, Brazília, Peru, Bolivia.
Boa c. constrictors from the Amazon basin are probably the largest and the most colorful members of the species. Although James Oliver mentions a 5,5m (18 ft) long specimen in his book, this snake turned out to be a misindentified Green anaconda (Eunectes murinus). Actually, adult animals kept in captivity are much smaller, around 2,2 m (7 ft) long and usually will not reach even 3 m (10 ft). However, captive specimens often tend to be smaller than speciemens living in the wild.
Abberant patterned speciemens often come up, especially in eastern populations. Number of dorsal blotches are between 15 and 21.
Older boas sometimes loose their beautiful light colors by age and turn into rather dark, "ugly " looking specimens.
Boa c. melanogaster is not a valid subspecies anymore, however it is a local, existing form of Boa c. constrictor.
In the Northern and Southern borders of distribution there are no natural barriers between constrictor and other subspecies, so we assume that transitional forms may occur in those regions.
1.1 CB 2007 Argentine boas
(Boa c. occidentalis)details..