The whole article is a bit tongue-in-cheek, with it's references to "terrifying" even though it also says they're harmless
A spider the size of the palm of your hand sounds pretty terrifying to me no matter how harmless it is, but then I really don't like spiders of any size.
I was shocked to come back and now find 17 points on it. Some people are absolutely petrified by spiders, and I take great joy in taking the harmless ones and letting them crawl on my hands and so on. They're a very polarizing creature
Having come across them in Japan many times, they can get as big as 10 cm across. Slightly less than a hand, but still extremely distressing when you run face-first into one.
Some jerk is going to bring spiders and it will turn out that they're perfectly adapted to the Martian environment and it will just become the spider planet.
A spider the size of the palm of your hand sounds pretty terrifying to me no matter how harmless it is, but then I really don't like spiders of any size.