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Posted

They frequent the flat in Gauteng, South Africa, where a friend of mine lives, much to her dismay. (She'd especially like to know if its venomous.) The specimen here is about 4 cm long.

 

Posted
They frequent the flat in Gauteng, South Africa, where a friend of mine lives, much to her dismay. (She'd especially like to know if its venomous.) The specimen here is about 4 cm long.

 

 

Well It's obviously an arachnid, a spider, maybe in the trap door spider family. It closely resembles a spider we have here in the South East US, the garage at my old house was full of them. Possibly one of these spiders...

 

 

Eresidae (velvet spiders, social spiders, buck-spoor spiders)

Posted
They frequent the flat in Gauteng, South Africa, where a friend of mine lives, much to her dismay. (She'd especially like to know if its venomous.) The specimen here is about 4 cm long.

 

I am pretty confident that all spiders are poisonous. The question becomes is it dangerous to humans. In most regions the "dangerous" varieties are well documented, so if you don't know, and none of your neighbors know, then you are probably not in danger. Be careful anyway.

 

Bill

Posted

The photo is not really good enough for ID purposes, but I would say it is a Velvet Spider of the family Eresidae.

 

South African Spiders by Martin R. Filmer has this to say:

The eresids are corpulent spiders, with the carapace bluntly rounded in front, and they usually have thick, short legs. They all possess a cribellum and calamistrum. The median eyes are set close to each other, while both pairs of lateral eyes are set far apart from them. There is usually sexual dimorphism, with the males being smaller and different in colour. Behaviourally, the erisids can be both arboreal and terrestrial.

 

being of mono colour, while most genera are decorative, I would say it belongs to the genus Gandanomeno (Common Velvet Spiders)

 

Again from South African Spiders by Martin R. Filmer:

Spiders of the Gandanomeno genus are black or dark brown to reddish-brown and are covered in fine hairs, giving them a velvety appearance. The cephalic area in both males and females is weakly raised, with the fovea present as a circular pit. It has a cribellum which is bipartite. Gandenomeno is usually found under loose bark or in crevices and old knot holes of trees. They build a funnel like web into a crevice, with the entrance to the web sheltered under a tarpaulin-like, flat and solid web, anchored to the substrate by scalloped, tough, silken threads.

 

Contrary to TheBigDog's believe, they are not poisonous. :friday::painting:

 

Oh, and the book say 12-30mm in size.

 

Mynah, I would love you to test this info against your friend's pets and report back. Well only the looks, not the poisonous part. :turtle:

 

By the way, do your friend has any plant growth near her windows. Your weather in Gauteng was a bit weird lately, so they might be attracted to a cooler environment indoors.

Posted

Thanks everyone - evidence seems quite conclusive! I'll ask my friend if she'll send a full frontal close-up, but am not sure she'll be willing to comply.:painting: (Her 4 cm estimate may be a bit excessive, but we all know what fear can do...)

Posted
I stand by them being venomous, but I find no indication that they are among those spiders who are a danger to humans.
As I understand it, all spiders are venomous but only a few can pierce human skin. So, if you have open sores, I guess any house spider could be unpleasant. Trivia question, what is the common name of the UK's only capably venomous spider?
Posted

you are talking about false widows, no? (steatoda nobilis)

 

its not the only one, one of very very few, but probably the most wide-sread species that can cause a pretty painful bite...

 

other then that, it is not unlikely that one may see a brown recluse, as they are spread so widely around the world, but yeah false widow would be the one you are referring to

Posted

Forgot to mention they're mostly in the garage, rather than the house.

 

Round here we have an unremarkable creature called a sac spider. I got bitten by one (I think - didn't see it in action) a few weeks ago. It felt like a flea bite - small and very itchy - and I didn't think much of it until I woke up in the night and found four weals on my arm. Two days later it looked like this:

 

Posted

sure it was a spider? pretty hard to get bit by most spiders, possible but not as common as thought.

 

and i think almost every single spider is venomous...but the back of my noggin tells me there is a few species that lack venom glands or fangs or something....too long ago to remember.

 

many spiders are just too tiny to bite humans, thats why the oh so toxic black widow has so few bite records, cause its just SO HARD to get bit by them. that and the fact many of the super toxic spiders are not as aggressive (although some are).

 

I am not too sure about your spider, but from that picture, a specie ID will be impossible.

Posted

Although I didn't see the culprit, I'd say it was most likely a sac spider (Cheiracanthium), as:

 

These spiders are common at the locality;

They are less reclusive than violin spiders, and often bite when accidentally trapped between skin and clothes;

The itchiness, followed by blistering, is more consistent with sac spider bite than that of the violin spider, which is usually painless, but causes worse necrosis.

 

I also know of no other arthropod bite that causes the same set of symptoms.

Posted

I'd love to show my friend the critter that surfaced when I watered the garden yesterday - but she might stop visiting... :hyper: It is enormous: Though I thought it best not to take a direct measurement, the post on which the spider is sitting measures 4 cm on the left side and 12 cm on the right. Any guesses as to its identity?

 

Posted
I'd love to show my friend the critter that surfaced when I watered the garden yesterday - but she might stop visiting... :) It is enormous: Though I thought it best not to take a direct measurement, the post on which the spider is sitting measures 4 cm on the left side and 12 cm on the right. Any guesses as to its identity?

 

 

Try the rain spider. Picture here shows the white band with black border. I would guess thats an ID point.

 

Spider Club of Southern Africa

 

additional info:

 

Fishing Owl

Posted

Thanks - hard to decide, though. It does not seem to be the local rain spider that I know well - that one is darker and somehow different-looking, although without a live specimen at hand the difference is difficult to pinpoint. I showed it to my sister, who also thought it was a different species. Still, it is very possibly a relative, and if I spot my garden pet again, I'll know what to look for!

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