Yesterday morning I hadn’t yet put on my glasses when I surfaced from the bedroom and went into the lounge.  I glanced across at the fish tanks, as I normally do, and noticed something strange. There appeared to be a mythical, multi-legged beast with two heads writhing around on the floor of the tank.

Skylla?

Glasses on, I peered closer. It seems there was a wedding last night. I made myself a cup of coffee, pulled up a chair and settled in to watch the show. (I know this might seem like a weird thing to do, but it’s not every day you see a pair of river crabs mating in your living room.) Three hours and a couple more cups of coffee later things had not progressed much, so I turned to Google to find out what I would be missing if I left them alone to carry on their, um, business … What I learned was that crabs usually mate soon after moulting, while their outer shells are still relatively soft and supple. Also that females of many African river crabs species (Potomanautes sp.) ‘give birth’ to live, perfectly formed baby crabs – unlike sea crabs which lay eggs that hatch into a larval stage before metamorphosing into little crabs. Another thing I learned is that the crab mating act can sometimes take many days to finish (!), so I gave up being a voyeur and went to work. In the evening when I got home they were still at it and only finally parted at around 8pm. I leave you with a short video I took. This is pretty much as exciting as it got and I think you will understand why I didn’t stick around to watch more.