Author: Thomas Ezendam
As a collector of mainly African Baboon spiders I think that they are underestimated.
People think they are too aggressive, sometimes too poisonous and mainly never visible. Especially the burrowing spiders are underground most of the time and only come out at night and only if they're hungry. That's totally true but if they come out, you'll see you have a beautiful spider. Just like Ceratogyrus darlingii .
Together with the genus Sphaerobothria of South America, the genus Ceratogyrus attracts the attention by having a horn growing out of its foveal groove. What the purpose of this horn is, is still in research but probably for the storage of food. The expandable intestine is situated just below this horn and probably can expand in the blood filled horn for storage of food. Indispensable for animals living in these areas.
There are 7 species in this genus: Ceratogyrus bechuanicus, Ceratogyrus brachycephalus, Ceratogyrus cornuatus, Ceratogyrus darlingii, Ceratogyrus dolichocephalus, Ceratogyrus marshalli and Ceratogyrus sanderi.
The genus is present in Southern Africa (Zimbabwe, Mozambique, Namibia, Botswana and the Transvaal). The habitat consists of dry forest and savannah, where they build deep burrows to escape from the heat.
The species which I have bred is Ceratogyrus darlingii or the East-African Horned Baboonspider. This spider lives in Botswana, Zimbabwe and Mozambique. It's one of the best known Horned Baboonspiders together with C. bechuanicus. The horn from the last one is, however, smaller and more flattened down, also it has a distinctive star shaped pattern on its cephalothorax. My spider is kept in a tank with a lid on top (12 x 12 x 12 inches). This tank is situated in a room which has a temperature of 25C.(summer 27C., in winter 23C. depending on temperatures outside). The humidity is controlled by pouring water in the tank. The substrate I use is peat. The decorations in the tank are a sheep-skull and a container of drinking water. The spider has constructed his home between the skull and the front and side pane.
I traded another spider to get the male on a meeting of the Dutch Tarantula Society. This was already an adult so I didn't wanted to wait to long. According to Klaas, the animals are very nervous during mating. Even footsteps could result in the male being grabbed by the female. Knowing this I placed the male on 20th November 1995 in the tank of the female and waited anxiously. The male walked across the skull right to the entrance of the females nest. This nest was at t he time no more than a big mat of silk. As the male touched the female, she got frightened and retreated. The male followed her and at the second attempt she was willing to mate. She just let him do his thing and didn't react aggressive at all.
After the mating she let him just sitting next to her and I removed him. No aggressiveness at all. I was just in time. The male died a couple of days later. I think of old age because he wasn't bitten or anything.
Now came the most difficult part for me: waiting. In this time I cleaned the whole tank and also changed the substrate. The decorations were placed on the same spots and the female started to build a new nest. This was now tube-shaped.
In the beginning of April the silk got thicker and thicker and on the 7th of April 1996 you could see a white mass attached between the frontpane and the skull. This was an eggsac. (Most African Baboonspiders don't hold the eggsac in their fangs like the American Theraphosids do, instead they fix it somewhere save and guard it.).
Most of the time she was lying across the eggsac as if she was protecting it. I was glad to have an eggsac of her but she choose the wrong time. A week later I was going to move. During the trip I left everything in the tank like it was. After the trip she was holding very firmly to the eggsac. Luckily everything went well. On the 15th of may 1996 (38 days after egglaying and a month after moving) I was gladly surprised at my daily round (at about 22.30 hrs). Through the silk I saw a tiny spider and as I looked better I saw that the whole nest was filled with them. They were still in their second instar (?)
On the 16th of may 1996 I took the young ones out of the tank and putted them in small containers. In every container I placed 10 young. Totally I had about 175 young. In the containers I had placed a piece of toilet paper in the shape of a basket. I made this paper damp twice a day. On the 4th of June 1996 the first spiderling moulted. I noticed that the exoskeleton hardened very quick and that they were very veracious. Within a few hours they were eating their family members. On the 16th of June 1996 the last one moulted and the end result was 132 spiderlings.
Raising them is no problem as long as you keep in mind that you can't keep them too dry. Remember that when they are born it's the raining season in their home-land. After these results, I thought that the female would go into moulting very soon. She ate very good and kept changing the look of her nest. I was very surprised to see an eggsac on the 19th of December 1996. I did notice more silk in the nest but I thought it was because she would go into moulting very soon. I started counting and thought that the young should come out around the 26th of January 1997. I had to wait again. In the time between I noticed, as I look back, that the female wasn't lying on the eggsac as much as she used to with the first one. Instead she was sitting in the entrance of the nest keeping watch.
On the first of February 1997 still nothing happened and I took out the eggsac and opened it. There were 5 first instar young and about 110 eggs with a white point on top. According to one of the members of the Dutch Tarantula Society this was a good sign and the development of the eggs stayed behind because of the temperature drop in winter. On his recommendations I putted the eggs into a small open container and placed this container in another one which had a layer of moist toilet paper on the bottom. The five young animals moulted to second instar within a few weeks. One of them died during this moult. Just after moulting another one died. There are only 3 left now and two of them are very blown up and shiny. With the first ones these were the ones that died the quickest. Time will tell.
Comparing to the first eggsac this was a major disaster. I think that the female didn't have enough sperm left to fertilise the eggs. On the last meeting of the Dutch Tarantula Society I bought a sub-adult male C. darlingii and a sub-adult male C. bechuanicus. We will see what the future will bring us. Just a few last words. Do not underestimate the African species. They are beautiful animals who have interesting behaviour. Like, why was the female so often on top of the first eggsac ? Defence ? I have to admit that it occurred to me as if she was incubating the eggs. For example with Bumble bees this is normal behaviour. Could a spider do this also ?
Next time I will try to find out by using a special thermometer.