Size and weight- The Colombian rainbow boa is the smallest of the rainbow boas, reaching lengths of 3 to 5 feet on average.
There is a clear sexual dimorphism between male and female, with females being significantly larger in both length and girth.

Coloring- Generally uniform brown in color with large dark edged vertebral rings and light centers forming saddles, there may also be a slightly off-center 'S' pattern.
Through a process called metachrosis, rainbow boas exhibit a day-to-night color change.
Primarily noticed in that their pattern will become lighter--almost silver--and have a molted silver sides and bottom.
Although individuals of abnormal colors and patterns exist--for example those that exhibit pigmentation disorders such as albinism, they are very rare in the wild and are often found in captivity where these mutations are often bred.

These pictures provide a good example of the day-to-night color change;
both pictures are of the same snake.
Pictures were taken 3.2 hours apart.
Size and weight- The Colombian rainbow boa is the smallest of the rainbow boas, reaching lengths of 3 to 5 feet on average. There is a clear sexual dimorphism between male and female, with females being significantly larger in both length and girth.
Coloring- Generally uniform brown in color with large dark edged vertebral rings and light centers forming saddles, there may also be a slightly off-center 'S' pattern. Through a process called metachrosis, rainbow boas exhibit a day-to-night color change. Primarily noticed in that their pattern will become lighter--almost silver--and have a molted silver sides and bottom. Although individuals of abnormal colors and patterns exist--for example those that exhibit pigmentation disorders such as albinism, they are very rare in the wild and are often found in captivity where these mutations are often bred.
These pictures provide a good example of the day-to-night color change;
both pictures are of the same snake. Pictures were taken 3.2 hours apart.
Epicrates maurus