Orange Baboon Spider, OBT (Orange Bitey Thing), Mombasa Golden Starburst Tarantula
Pterinochilus murinus
Theraphosidae (Tarantulas), Order Araneae. Characterized by dense urticating hairs (though this species lacks them) and large size.
Physical Description
A robust, medium-sized tarantula with a heavily sclerotized cephalothorax and a bulbous abdomen. The entire body is covered in thick, bristly setae (hairs). Unlike New World tarantulas, it lacks urticating (stinging) hairs and relies on speed and venom.
Size Estimate
The specimen appears to be an older juvenile or sub-adult with a leg span of approximately 3 to 4 inches (7-10 cm). Full-grown adults reach a 4- to 6-inch leg span.
Coloration & Markings
Distinctive vibrant orange to golden-tan coloration. The carapace features a 'starburst' radiator pattern of darker lines radiating from the fovea. The abdomen has a dorsal pattern of dark spots and chevrons.
Web Type
Extremely prolific heavy webber. It creates thick, silk-lined tunnels and sheet-like retreats that may cover the entire floor and walls of its habitat.
Eye Arrangement
Small, clustered eye tubercle on the front of the carapace containing eight eyes in two compact rows, typical of the Theraphosidae family.
Leg Characteristics
Thick, powerful legs designed for both sprinting and climbing. Feet have dense scopulae for gripping surfaces. Posture is often defensive when disturbed, with front legs raised.
Venom & Safety Information
Venom Information
Neurotoxic venom. While not considered life-threatening to healthy humans, it is significantly more potent than that of New World species, causing intense pain, cramping, and swelling.
Medical Significance
Moderate danger. Bites cause severe localized pain, muscle spasms, and systemic discomfort. There is no specific antivenom; treatment is symptomatic (pain relief and muscle relaxants).
Safety Recommendations
Relocate only using the 'cup and board' method with long tongs. Never attempt to handle this species by hand. If bitten, monitor for severe muscle cramping and seek medical attention if symptoms worsen.
Habitat & Behavior
Habitat & Range
Native to Central, Southern, and Eastern Africa. They are highly adaptable, found in arid scrublands, savannas, and forest edges, often occupying burrows or crevices.
Behavior & Temperament
Famous among enthusiasts for its defensive and aggressive temperament. It is extremely fast and will likely 'threat pose' (raising front legs and baring fangs) or strike rather than flee.
Diet & Prey
Opportunistic predator feeding on crickets, roaches, grasshoppers, and occasionally small vertebrates. Uses a sit-and-wait ambush strategy from its silk retreat.
Seasonal Activity
Year-round activity in tropical regions, with increased movement and mating behavior during the rainy seasons when humidity is higher.
Description
Known in the hobby as the OBT, this African tarantula is a marvel of adaptation. Its bright color serves as a warning of its volatile temperament and potent venom, making it a favorite for experienced keepers.
Key Features
Electric orange color, starburst pattern on the carapace, lack of urticating hairs, and heavy silk production in its enclosure.
Similar Species
Pterinochilus lugardi (duller color), Pterinochilus chordatus (greyer tones). It is easily distinguished from New World 'orange' spiders by its lack of tibial spurs in most color forms.
Life Cycle
Females can live up to 12-15 years, while males live 3-4 years. Reproduction involves the female producing a silk egg sac containing 75-150 eggs which she guards fiercely.
Ecological Importance
Acts as an apex invertebrate predator in its native range, controlling insect populations and serving as a food source for larger birds and mammals.
Conservation Status
Not listed by the IUCN. Generally common in its range, though local populations may be impacted by the pet trade collection if not captive-bred.
Interesting Facts
Despite its bright 'warning' color, some regional variations are actually grey or brown. It is nicknamed 'Orange Bitey Thing' by keepers due to its hair-trigger defensive response.
Photography Tips
Shoot through clear enclosures or during feeding when the spider is stationary. Use a fast shutter speed to catch its rapid movements and macro settings to highlight the starburst carapace.
Identified: 2026-07-06T20:13:03.046308