Mouse spider - Scotophaeus blackwalli
Photo: Kersti Nebelsiek / License

The mouse spider (Scotophaeus blackwalli) is so called not because it eats mice but because it has a lovely soft furry abdomen just like a mouse! I for one am quite relieved about this. Another thing to be pleased about is it isn’t related to the Australian mouse spider which probably would have a go at a mouse.

The mouse spider is relatively common throughout the UK, although not seen in the far north. It prefers the indoors, which might suggest it was once native to warmer climes. Often seen in sheds and attics it can sometimes be found outside, under the bark of trees. It has been noted that those found outdoors are considerably bigger than those inside.
The mouse spider can measure up to 12mm along the length of its body, making it a touch smaller than a large false widow.

S blackwalli can give people quite a fright owing to its nocturnal hunting habits. It may be spotted creeping along walls and ceilings looking for prey. Not what everyone wants to see when they turn the light on for a midnight pee!

The European mouse spider is one of the few species of spiders found in the UK that are capable of inflicting a bite on humans. They have sufficiently large fangs to penetrate the skin and the bite is described as being painful. One report states the bite resembled a pimple with a pus-filled head surrounded by red. This led to the whole hand becoming infected. Whether this is directly attributable to the spider bite is difficult to know.

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  1. Cheers,was just making sure the Spider️I caught wasn’t a Brazilian Wanderer☠️ that had got in my house by stowing away in a punnet of Brazilian grapes that I frequently buy.I found this very helpful.Thanks again

  2. Omfg! One of these just ran out from my iPad I’m watching bed. Never seen one before but managed to catch it. I do not do spiders! They seriously freak me out. Only came here to try and identify it and yes it was one of these aargh.

  3. Found one on the carpet last night and caught it with our bug kit for the children to see this morning. Very docile (whilst in captivity). About to put out on the bug house. Thanks for helping with the ID.

    1. They would have an open buffet in the big house, they hunt other spiders. They are fine really, they can move quickly though so some people get a freight. Fine too pick up once you don’t squeeze it or poke it’s face end.

  4. Typical…I’m convinced the one in my shed is one of these, except mine is jet black, and more disturbingly…25mm long 🙁 I got as near as I dared with a tape rule.
    It’s the same shape, just bigger and black.

    1. Sounds like you have a Tube Web spider female, they are big beautiful black spiders with blue/green irridescent fangs. They aren’t native but have been here so long they are naturalised.

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