The small horn size of this individual is apparent as she guards her eggsac.

Greater Horned Baboon Ceratogyrus sp. (aka pet trade C. brachycephalus) These are spiders from the same subfamily as Pterinochilus spp.  Like their cousins, they grow quickly, web profusely,  and prefer a somewhat drier habitat.  They are distinguished from other species of tarantula by a unique forward-facing "horn" that arises from the center of the carapace.  Contrary to its namesake, different individuals of C. brachycephalus may or may not have a very large horn; it may be so small as to resemble the horn of C. sanderi, which is more of a plug than a protuberance. Some hypothesize that the small-horned spiders sold as C. brachycephalus in the pet trade might be C. sanderi or perhaps a hybrid (thanks to P. messenger of The Tarantula Store for that info).  Typical of the members of the genus Ceratogyrus, this spider has a pale band on the underside of its abdomen.

Range: The Greaterhorned Baboon comes from southern Africa, in Botswana and Zimbabwe.

Habitat:  Semi-dry scrubland

Size: Small for a tarantula.  Though I have seen specimens at over 5" in legspan, I have successfully bred a female that was a mere 3 1/2" at maturity.  The male, which was mostly legs, was about 3" in span.

Attitude:  Generally quite defensive, but I have seen some healthy individuals that are much less high-strung than others.  I haven't come across a specimen that would sit still for handling and most would bite if provoked enough.

Dwelling: They love to dig, and they like to web even moreso!  I've seen sub-spiderlings just past the "eggs-with-legs" stage that began webbing a fair amount.  Once they molt into actual feeding spiderlings, there is no end to their webbing endeavors.

Ideal Setup: A 2.5 to 5 gallon container with enough peat/potting soil for digging in (fill it about 4-8 inches deep).  Supply a water dish.  They like it somewhat dry, but moistening the soil or misting may be appropriate in August/September to mimic the S. African wet season if desired.  I've noted that my female will not lay eggs in the summer if the substrate isn't moist. Keep the temperature around 75-80 degrees F if possible.

Food: Any bugs that haven't been exposed to pesticides (3-5 crickets a week for adults); baby mice.  Spiderlings love to eat and will take on prey their size quite readily.
 
 

This is the post-molt coloration.  Note the patterning on the opisthosoma.

The female on the left is not a large spider.  Note the diminutive size of the male in relation to her.