First South Brazilian boas were collected in the end of 1970ies, and early 1980ies. In 1982, the biggest reptile importer company at that time, namely Pet Farm brought the first significant shipment of South Brazilian amarali that contained 40 specimens.
These boas all come to the US as "Bolivian boas" with legal CITES paperwork. Some souces- including ourselfs -suspect that these boas had originally been collected in South Brazil, than smuggled to Bolivia to export them from there, as Brazil was closed for live animal export that time.
Anyhow, after those animals had arrived to the US, all the specimens ended up in Joe Terry's stock, who bred them successfully in '86, '87 and '89, creating 3 original, unrelated bloodlines. Although several of these original 40 specimens got to various hobbyists, nowadays most of South Brazilian boas come from Joe Terry's bloodline. Most of them have steely gray color, thus they are called "Silverbacks".
There existed a more yellowish, pastel colored bloodline called "Orange Crush", which was created by combining Terry's 86 and 89 bloodlines. Kevin Barnett also bred them in 2004 and that was the last known breeding of Orange Crush line. Unfortunately, US boa enthusiasts did not make efforts to maintain this line, most of them were bred to "silverback" lines later. We suppose Orange Crush line have disappeared from the market for good.
South Brazilian amarali are well-known in Europe for a long time due to the danish bloodline. These snakes had originally been captured in Sao Paulo and than brought to Europe by a danish professor in the 1980ies. Specimens from this line have also grayish basic coloration with more blurred patterns. Thanks to their weak health conditons and sensitiveness, danish bloodline become notorious among boa keepers. Most of juvenile specimens died within first year of their life, owing to their high proneness of regurgitation syndrome. Those who can pull through the early years, otfen died after changing owners and getting ill.
South Brazilian boas are not really attractive looking snakes, their appearance often seems to be overall gray. Nevertheless, they are very popular in the US and have a higher demand.
Adult females could reach 2 m (6,5+ ft) in length, but they are definitely smaller than Boa c. constrictor. They also have noticeably thicker bodies than any other forms. Number of dorsal saddles- that could be both "widow peaks" or ourglass-shaped patterns -are 22 or above. On the posterior third of the body, the remarkably short tail with small dorsal patterns is clearly recognizable.
Ventral surface is grayish, sometimes with a pink hue and heavily spotted. The head seems to be- like in case of Boa c. constrictor -horizontally plated a bit. According to herpetologists, they take advantage of their grayish, dark coloration when they are basking.
Breeding of South Brazilian boas have been achieved several times in the United States. Juveniles often show a defensive posture, when they are disturbed and are trying to affray their keeper by hissing and opening their mouth. As the time goes by, usually they will loose that aggressive temper. However, they are seemingly more uncomfortable with handling than other subspecies in my experience. Although South Brazilian boas from American stocks do not tend to regurgitate, they should be fed with moderate sized preys.
1.1 CB 2007 Argentine boas
(Boa c. occidentalis)details..