Boa Constrictor Imperator (BCI)

Boa constrictor imperator
Morph: Hypo Motley IMG 66% Het Snow

Species Overview

• Size: BCI typically reach 6–8 feet (1.8–2.4 m) in length, with females usually larger than males. Adults often weigh 15–30 pounds depending on genetics and husbandry.

• Appearance: This boa expresses three traits:

  • Hypo (Hypomelanistic): Reduces black pigmentation, brightening colours and sharpening pattern contrast.

  • Motley: A co-dominant pattern mutation that alters saddles into connected or ladder-like shapes, sometimes forming striping.

  • IMG (Increased Melanin Gene): A co-dominant mutation that darkens the boa over time, often leading to nearly jet-black adults.
    It is also listed as 66% Het Snow, meaning there is a two-thirds probability it carries both Albino and Anerythristic genes, though these are not visible. The combined effect creates a unique boa that darkens with age while displaying modified patterning and brightened Hypo influence.

• Distribution: The natural Boa constrictor imperator is native to Central and South America, ranging from Mexico through Colombia.

• Habitat: Wild BCIs inhabit tropical forests, scrublands, savannahs, and river systems.

• Behaviour: Primarily nocturnal ambush predators, feeding on small mammals, birds, and reptiles. They are strong swimmers and occasional climbers, though adults are mostly terrestrial.

Captive Care

• Enclosure: A naturalistic enclosure is recommended. Adults require at least a 6′ × 2′ × 2′ enclosure with climbing branches, cork bark, multiple hides, and plant cover. Bioactive setups with soil substrate, live plants, and leaf litter support humidity and enrichment.

• Temperature & Humidity: Maintain a gradient of 80–85°F (27–29°C), with a basking area of 88–92°F (31–33°C). Nighttime drops to 75–78°F (24–26°C) are acceptable. Humidity should remain between 55–70%, with a water dish large enough for soaking.

• Diet: Juveniles should be fed every 7–10 days on small rodents; adults every 14–21 days.

• Behaviour in Captivity: Hardy and striking boas, though individuals may show strong feeding responses. With consistent handling and husbandry, they generally settle well.

• Special Considerations: While selective breeding has produced a wide variety of morphs, their core care requirements remain identical to standard Boa constrictor imperator.

Genetics Note

The Hypo Motley IMG 66% Het Snow involves:

• Hypomelanistic (co-dominant): Brightens overall appearance and reduces black pigmentation.

• Motley (co-dominant): Produces connected saddles, striping, or reduced patterns.

  • ⚠️ Note: The homozygous form (“Super Motley”) is generally considered fatal in boas and does not produce viable offspring.

• IMG (co-dominant): Increases melanin production; boas darken progressively with age, sometimes turning nearly solid black.

• 66% Het Snow (double recessive carrier): A two-thirds probability of carrying both the Albino and Anerythristic genes, though not visually expressed.