The King Baboon - First Successful Breeding ?

I have been keeping specimens of the King baboon Citharischius crawshayi for up to eight years now and over those years I have tried and always failed when it came to captive breeding. Any attempts ended with the same result - either the male was simply killed on introduction; died later from injuries sustained from mating (lost legs etc.) or after a seemingly successful mating, the female failed to produce an egg sac. I was well aware of the King baboon's reputation as a difficult species to breed (all of the spiderlings that were available came from gravid wild caught females) and I think that the key to success lies not only in the pairing but, more importantly, the housing set-up of the female.

I acquired my main adult female specimen in 1994 and after trying several set-ups, she only really settled down when I constructed an artificial burrow. This consists of a medium sized container (12"x8"x8") with a hole drilled into the bottom. Into this hole there is a length of plastic tubing (the type commercially available for hamster runs) which curves to recreate the angle of the spiders burrow. This leads into a smaller container (a square-edged sweet jar approx. 12"x6"), which simulates the spiders chamber. On introduction the female immediately entered the tubing and settled very quickly into this artificial simulation. Activity and feeding increased and she even sat at the burrow entrance at night, legs just extending from the hole, awaiting passing prey as she would in the wild. The constant roaming of the tank ceased and she almost never left the confines of the tube and chamber.

Several months and a perfect moult later, one of my sub-adult specimens matured into a male so the timing and the conditions were perfect. Now for those of you who don't know the King baboon, these spiders are big. Females can reach a leg span of 9" and they are also very stocky. This is Africa's second largest spider (after Hysterocrates hercules) but in comparison, the adult male is lucky to be half her size and is rather thin-legged. To make matters worse, this species does not have tibial hooks or spurs and he has to rely on brute strength in order to lift the female into position. What the males lack in size they make up for with bravado and when introduced usually have no fear in tearing away the burrows silken veil and charging straight towards the female.

As with the many previous attempts, the pairing followed the usual routine. After making sure the male had built a sperm web (this is essential as unprepared males fail to even search for the female) he immediately located the burrow entrance and made his way down the tubing violently shaking and vibrating his whole body. Sensing his presence in the burrow, the female responded in the expected way - aggressively! She literally chased him up the length of the burrow and he made a speedy retreat out into the larger container. Unperturbed by this, the male advanced again and enticed the female out into the open and it was only then that the true size differences between the sexes became shockingly apparent. By this time the female was willing to mate and allowed the male to move into position, with much stroking of the front legs and securing her chelicerae to the best of his ability. As with previous attempts, the male lifted the female and he stretched his palps towards her epigynum. At this point the male seemed to hesitate for some reason and the female seemed to keep her epigastric furrow just out of reach while he took up this precarious position. Eventually the male did make contact with his her epigynum for a split second and then with a flurry of legs and a crunching of carapace, she grabbed him and dragged him down the burrow, leaving a few twitching appendages scattered around the burrow entrance.

Now in the past, I wasn't even sure that the males had transferred sperm successfully (this was the fourth male she had eaten) and gave little hope to a fertile egg sac being laid but this time, her behaviour over the following months indicated otherwise. She fed at every opportunity, her abdomen swelled and the webbing inside the chamber area grew thicker and thicker. On inspection of her tank some three months later, I noticed an egg mass suspended from the chamber walls in a perfect hammock-like web. Over the next two months, the female spent most of the time sitting under the egg mass but she did accept all food offered, sitting at the burrow entrance in the usual manner. She even presented herself at the entrance when I entered the room as if waiting to be fed.
Not wanting the eggs to dry out, I introduced water on a regular basis down the tubing and into the chamber but as the walls of the container were heavily webbed, viewing was restricted. Everything proceeded well for the next six weeks, disturbing the females container as little as possible (the chamber container was covered at all times with a sleeve of black card) but on inspection, I found her with the egg mass half way up the burrow tube. In moving the eggs (the only explanation for this behaviour being that the environment in the chamber was too humid) the female had split the mass and the small spiderlings in their pre-moult stage were strewn along the length of the tube. This forced me into making the decision to remove the egg mass from the female and try to artificially incubate the spiderlings. These were carefully removed from the egg mass as there were several dead eggs in the sac and I didn't want to lose any spiderlings due to mould etc. The spiderlings were placed in a small plastic cup wrapped in tissue paper and covered with a piece of fine netting. The whole cup was placed in a larger container and floated in water (this kept the environment humid but the tissue dry). Mortality was quite high but eventually, 3 months after they were laid a total number of 40 moulted out into fully mobile spiderlings.

After speaking with several members and friends about this pairing, it appears that this could be the first ever-successful breeding of C. crawshayi in captivity. If anyone has any information regarding this species and any previous breeding successes then I would be interested to hear from them.



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