Pterinochilus murinus, commonly known as the Orange Baboon Tarantula or OBT, is spread throughout the African continent's central, eastern, and southern parts. The species and the different localities are found in Mozambique, Botswana/Zimbabwe, Kigoma, Mikumi, Kenya, and the mountain regions of Usambara. Often recognized by its name, the OBT is one extremely defensive spider. It recurrently positions itself in threat posture, striking everything at arm's length, and therefore also known as the "orange bitey thing". Nevertheless, the Orange Baboon tarantula is a gorgeous species with its basic color pallet of either yellow, brown, red, orange, or a mixture of dark grey with bright colored rings on each appendage. On the dorsal side of the abdomen is the typical dark fishbone pattern and the star-shaped pattern covering the carapace. When the spider positions itself in threat posture, the bright iridescent coloration can be seen on the bottom of the tarsar (feet). This beast of a spider is the true definition of a nightmare on eight legs but it's also a remarkable species to work with.

Localities

Currently, there are five different color variations of this species, found in different localities.

• (BCF) Brown Color Form - Tete, Mozambique

• (RCF) Red Color Form - Mountain region of Usambara

• (DCF) Dark Color Form - Botswana/Zimbabwe, Kigoma, Mikumi, and Kenya

• (TCF) Typical Color Form - Kenya, Mozambique

• (OCF) Orange Color Form - Mountain region of Usambara

The OFC variation used to be named UMW before RFC was discovered.

Natural Environment

In the wild, the spider has evolved to be tolerant of the harsh African environment. Due to the large geographical spread of the species, from Kenya to Zimbabwe and partially Botswana, they are observed in both more and less humid environments. However, most localities inhabit some savanna with either less vegetation, partial vegetation, or some of the mountain regions of Usambara. Throughout the warm and rough climate, the spider usually retreats to its burrow which allows them to adjust the temperatures by traversing deeper. When the sun starts to fade and temperatures begin to drop, the spider becomes active in search of either prey or maintenance and web construction close to the hide. 

Behavior

Besides being a beautiful species of the African fauna, the Orange Baboon Tarantula is considered to be one of the most aggressive and defensive spider species within the Theraphosidae (tarantula) family. The venom is considered medically essential and a bite will be extremely painful, not lethal, but medical attention is recommended after being bitten. Symptoms of intense muscle cramps, pain, nausea, fatigue with local swelling and soreness.

In general, the species are categorized as skittish and easily threatened. Filling the water dish can be a fight in itself. When they feel threatened, they often react with their typical threat posture by displaying their hind legs and fangs with potential striking attempts. The species are also known to stridulate. Even though this species is prone to feeling threatened which also means they can easily become stressed, it’s important to provide an enclosure suitable for the spider with plenty of hiding opportunities. Less interaction equals less stress. This species should only be acquired by experienced keepers. 

Orange Baboon Tarantula is an excellent web-builder and can easily cover its entire burrow and the surrounding area with a thick layer of silk. The web functions as a protection and hunting mechanism as they are ambush predators, laying in its funnel-shaped webs waiting for prey to wander by. An interesting note about their preferences regarding the burrow is that they often seek abandoned ones of previous owners such as termites or other invertebrates to make their own. If they are given a choice of either digging from scratch or moving into the already existing one, they prefer to start decorating right away. However, they are semi-arboreal, and when given the opportunity they make use of trees, rocky hills, and bushes by building funnel-shaped structures from their burrow. 

Enclosure/Terrarium

Terrarium: the ideal enclosure for this species should primarily provide substrate depth rather than height, though it can be included but not as an arboreal setup. As semi-arboreal species, they often connect the burrows with tunnels both underneath and above ground when given the opportunity. Adult specimens should be housed in an enclosure with the minimum size being 30x30x30 cm (12x12x12"). As for juveniles and spiderlings equally important to house them in enclosures with the appropriate substrate depth. 

Substrate: Pterinochilus murinus is an opportunistic burrower and web-builder, and should therefore be provided with the required amount. Spiderlings should be provided with a substrate depth of a minimum of 5 cm (2 In). For juveniles, sub-adult, and adult specimens it's recommended to provide a depth of minimum 10 cm (4").

Plants: due to the medium humidity requirements of approximately 65 - 70%, it's important not to use plants with high watering needs. Therefore, succulents are the most prominent plant choice for low-humidity-required spider species. Plants are an efficient way of providing more decoration within the enclosure which serve two functions: it's great for web-building species as it provides possible anchor points, and it gives the overall esthetic touch. Therefore, I do personally recommend succulents in all shapes and colors as long as it is safe for the spider - Recommendation: Dracaena trifasciata, Aloe vera, Succulents, Zamioculcas zamiifolia, or Chlorophytum comosum.