BABOON SPIDERS - Family Theraphosidae (Mygalomorphae)

In Africa, these spiders are known as Baboon spiders because of their hairy appearance and because the colour of the pads on the tarsus resembles the colour of a baboon’s foot pad.  In other parts of the world, members from this family are commonly known as Tarantulas.  Baboon spiders are very large spiders with thick legs that do not get narrower toward the end.  They live in silk-lined burrows and emerge only at night to hunt, but never move far away from the burrow.  They can live up to 25 years if they do not fall victim to predation.

Baboon spiders can be differentiated from Wolf Spiders (Family Lycosidae) by the distinct eye pattern – 8 small eyes in a tight cluster on a protuberance at the front of the cephalothorax.

They will not go out of their way to attack humans, but would rather retreat without a fight.  In Masai Mara, there is only one species of Baboon Spider, Pterinochilus chordatus.  In Kenya as a whole, there are only 7 KNOWN species (very limited work has actually been done studying Theraphosids in Kenya, and there are very possibly more than 7).  Owing to its large fangs, it can inflict a painful bite.  The venom can cause severe pain at the bite site and a tight chest, but no major systemic effects.

LIFESTYLE: Sedentary and ground-living

HABITAT: In Burrows

BODY SIZE (excluding legs): 13-64 mm

ACTIVITY: Nocturnal

DANGER: All are harmless except for Pterinochilus murinus (found in central and South-Eastern Kenya)

 Above: Pterinochilus chordatus - BABOON SPIDER.  Common in Southern and Central Kenya.  Notice the eye pattern - very distinct from that of a Wolf Spider (Lycosidae).  Here, eight small eyes are all grouped together in a tight bunch on a raised protuberance in front of the chelicerae (fang bases).

 Above: Pterinochilus chordatus - BABOON SPIDER. Notice the width of the legs does not vary much from the base to the tip - differing from the pointed feet of a Wolf Spider (Lycosidae).  Notice also the horizontally positioned chelicerae (fang bases) compared with the very vertical chelicerae of Lycosids.

Above: Eucratoscelus sp. - BABOON SPIDER.  Found in Central, Northern, and South Eastern Kenya - this was taken in central Laikipia.  (Photo Credit: Sophie Woodrow)

Above: Eucratoscelus sp. BABOON SPIDER. Again, notice the distinct eye pattern - very different from that of a Wolf Spider (Lycosidae).  Also, a fully grown Baboon Spider will generally be much bigger than a fully grown Wolf Spider - they can be almost twice the size.