Boaconstrictors.co.za

Boa constrictors and Boa imperator

Boa constrictors are large, non-venomous snakes native to the Americas, primarily found in tropical rainforests, savannas, and arid regions from Mexico to Argentina. They are known for their distinctive method of killing prey—by constriction—and their adaptability to various environments. These snakes can grow quite large, typically ranging between 1.8 to 3 meters, though some individuals exceed these sizes.

Taxonomic History & Name Changes

Historically, all boa constrictors were classified under a single species, Boa constrictor, with various subspecies. One of these was Boa constrictor imperator, commonly called the “Central American boa” or “common boa,” which is widespread from Mexico down to Colombia.

However, in recent years, genetic and morphological studies have led to taxonomic revisions. Many herpetologists now recognize Boa imperator as a distinct species rather than a subspecies of Boa constrictor. The key differences include:

  • Size & Morphology: Boa imperator is generally smaller and has slightly different scalation patterns compared to Boa constrictor.

  • Geographic Range: Boa imperator is found mainly in Central America and northern parts of South America, while Boa constrictor (sensu stricto) is more commonly found in South America.

  • Genetics: DNA analysis has shown enough genetic divergence to warrant separating them into distinct species.

  • Boa sigma is the species which is confined to the western part of the extension in North America.

 

Current Taxonomy (which may change at any time)

  • Boa constrictor (South American Boa constrictor)

  • Boa imperator (Central American boa, formerly Boa constrictor imperator)

Despite this change, many reptile enthusiasts and pet traders still use “Boa constrictor” generically to refer to both species, causing some confusion. In South Africa there are very few pure Red tail boa constrictors ie Boa constrictor and as a result all the boas we know are Boa imperator or the Common boa.

Pure Redtails are more difficult to breed and occur in areas which are dominated by drug cartels, militia forces and restrictive export laws. The boas that will be discussed here are Boa imperator as they have the most number of colour and pattern varieties.

Recognized Species and Subspecies of Boa Constrictors

Over time, taxonomists have revised the classification of Boa constrictor and related boas based on genetic, morphological, and geographic differences. Here’s a breakdown of currently recognized species and subspecies within the Boa genus:

  1. Boa constrictor (True Red Tail Boa Constrictor)

  • Found primarily in South America, including Brazil, Venezuela, Colombia, Peru, and Argentina.

  • Generally larger than Boa imperator, with some individuals exceeding 10 feet (3 meters).

  • Known for more prominent saddle markings along the body.

1. Recognized Subspecies of Boa constrictor:

1.    Boa constrictor constrictor – Red-tailed Boa

  • Found in the Amazon Basin (Brazil, Peru, Colombia, etc.).
  • Has deep red or maroon tail markings.
  • Among the largest of all boa constrictors.

2.    Boa constrictor occidentalis – Argentine Boa

  • Native to Argentina and Paraguay.
  • Darker in colour with black and white speckling.
  • More cold-tolerant than other boas.

3.    Boa constrictor amarali – Bolivian Boa

  • Found in Bolivia and parts of Brazil.
  • Slightly shorter and more robust-bodied than B. c. constrictor.
  • Generally has a more muted pattern.

4.    Boa constrictor longicauda – Tumbes Peruvian Boa

  • Native to northern Peru.
  • Features distinctive golden and black patterning.
  • Smaller and darker in color.

5.    Boa constrictor orophias – St. Lucia Boa

  • Endemic to Saint Lucia in the Caribbean.
  • Threatened due to habitat destruction.

2. Boa imperator (Common Boa)

  • Formerly classified as Boa constrictor imperator but now a separate species.

  • Found in Mexico, Central America, and northern South America.

  • Smaller on average than Boa constrictor (typically 5–7 feet but can exceed 9 feet).

  • More variable in pattern and color.

  • Includes populations from islands such as Hog Island Boas, which are known for their reduced size.

Other Boas

3. Boa nebulosa (Dominican Boa)

  • A recently described full species, formerly classified as Boa constrictor nebulosa.

  • Endemic to the island of Dominica in the Lesser Antilles.

4. Boa sigma (Mexican Boa)

  • Recently split from Boa constrictor.

  • Native to Mexico’s Pacific coast, including Baja California.

  • Generally smaller than B. constrictor and more desert-adapted.

Summary of the Current Species in the Boa Genus:

1.    Boa constrictor – South American boa constrictor (with several subspecies).

2.    Boa imperator – Central American boa (formerly a subspecies of B. constrictor).

3.    Boa nebulosa – Dominican boa (endemic to Dominica).

4.    Boa sigma – Mexican boa (formerly Boa constrictor sigma).

These taxonomic changes have been driven by advances in genetics and molecular research, leading to a clearer understanding of the relationships between different boa populations.