The August Spider of the Month (SOTM) is this tree trapdoor spider (Moggridgea sp.; Migidae) photographed by Brad R Raath in Plettenberg Bay, Western Cape.
Tree trapdoor spiders, as the name suggests, often build their burrow retreats in hollows and crevices in tree trunks, typically those with thick bark. This silk-lined hollow is closed with a single trapdoor on a hinge. Some of these burrows are so perfect that one often wonders if the hole was excavated by the spider; however, in such cases, they probably chose an existing hole made by another animal. Still, the spider might be able to do very minimal excavation.
These spiders, like other trapdoor spiders and tarantulas, are mygalomorphs, which differ from “normal” spiders (araneomorphs) in having four book lungs instead of two, and fangs that strike downwards instead of crossing, among other differences. They also live much longer.
Regarding this find, Bradley said:
“One finds Moggridgea trapdoor spiders only with a little luck. Here in Plet, they are mostly found in the fynbos biome. This particular one was crossing my path during the middle of the day! Quite unusual… Last year I found a male Moggridgea more than a month later than this year. That one I found in my home.
Most females I find by accidentally digging them up while doing farm work. The last one I found by weeding out a plant that had grown its root into the trapdoor spider’s lid! By pulling up the weed, I removed the trapdoor spider’s lid! Accidental discovery. Although I put the trapdoor lid back in place, the spider discarded it, deciding to build a new lid rather than repair the hinge…”
There are 32 species of Moggridgea in the world, mostly from Africa. South Africa has the most species (20). The genus was named by O. Pickard-Cambridge (1875) in honour of John Traherne Moggridge (1842-1874), who was a British botanist, entomologist, and arachnologist.
Of 168 people who voted, this photo received 87 (52%) votes. This is Bradley’s first SOTM. He came in VERY close in May this year, when his hedgehog spider (Pycnacantha tribulus) tied with Kyle Thomas’ baboon spider (Augacephalus junodi). It eventually came down to a vote by the committee members to determine a winner. Congratulations, Bradley, and please keep on posting your awesome shots!