ARACHNIPEDIA for 2010

Surprise visit.

I HAVE three favourite spiders. Some would think that weird.

My first being the Australian redback. A Latrodectus spider, closely related to the infamous American black widow (we have far less-dangerous, related steatoda species in the UK, like the Nobilis [false widow] and Bipuncta [rabbit hutch spider]). My second favourite is the Fen raft spider (Dolomedes).
Thirdly, the woodlouse spider (Dysdera Crocata).
I'm particularly curious about the redback, as it is so commonly found in and around houses right across Australia, is dangerous, yet hasn't killed a human in decades. If I ever visited Australia, I'd be looking for redbacks everywhere, both through fear and interest.
The raft spiders are incredibly rare, so I'd also like to see one of them too, as they live in the UK, near streams and eat small fish!
Most of my knowledge about spiders is purely based on what I've read, not what I've seen! I'm enthusiastic about common spiders we find in our homes all the time, but I'm excited when I stumble upon an arachnid I've not only read about, but have taken the time to search for.

Dysdera Crocata (The woodlouse spider) has elluded me for years. Arguably one of Britain's most venomous spiders, it's an unusual looking animal. Red thorax, orange legs. Creamy grey abdomen, and MASSIVE chelicerae.
In fact, despite the fact I've read about this spider in great detail, watched youtube videos, read toxicology reports about its bite, written about it on this site, more than once! (CLICK HERE) (AND HERE), I have to admit I felt a teeny bit tentative when a young male strayed into my bathroom yesterday. I didn't have a light on, but, in semi darkness, identified it in my mind as a mere mouse spider (herpyllus blackwalli). I was wrong!
I was inquisitive and switched on the light. Bloody Hell, it's a woodlouse spider!
They aren't anywhere near deadly. They have a bite with very little neurotoxin, but it is very acidic, much like a wasp sting. People have been hospitalised by these spiders. I've always said though, unless you know which species it is, you should never handle a spider or scorpion.
Woodlouse Spiders aren't endangered, but they are quite unusual to find indoors, or to spot at all really.
They have the largest chelicerae of any spider in the UK, which is scarily obvious when you see one in the flesh!
They're not particularly massive spiders either. Very robust though. Like little, red armoured tanks.

So, the young male I kept from the other night.
It's easily identified as a male. It's abdomen is relatively slender. Females have bulbous abdomens. Males have a massive thorax. As with all spiders, the male has pedipalps (boxing glove-like bulbous feelers either side of its mouthparts). Pedipalps are sex organs in the spider world, but not in crustaceans. Evolution is very weird.

The young male dysdera crocata I kept has now been fed. I have him in a container. I found woodlice and he has eaten two.

A small mouse spider (herpyllus blackwalli) wandered into my flat earlier. I trapped it, totally humanely, and, as an experiment, dropped it into the woodlouse spider's tub. The woodlouse spider absolutely desecrated it. As far as I know, dysdera don't predate on other spiders, so I presume it saw it as threat to its food supply.

Anyway, I include some photos. Unfortunately, said Mr Woodlouse Spider chose to fold back his fangs for every picture, but I'll be keeping him for a while, as long as I have a supply of woodlouse! I'm determined to snap those bl**dy massive fangs!
I'm uploading three pictures. One of them shows the woodlouse spider walking away from the remains of the mouse spider I dropped in. And they WERE remains. It annihilated it! Click on any photo for a larger view.