My personal experiance of dangerous beasts in Greece are mosquito's, for some reason I am extremely tasty to them but what makes it worse I have a reaction to the bite.
During our travels in Greece we have seen several snakes squashed on the road, and only the tail end of one as it slithered away in the undergrowth.
Chris (hubby) did once get bitten by a small (about 8 inches) millipede, but thankfully it did no lasting harm. We were later told by locals that it was only a baby!
Also when travelling through the mountain region a land crab decided to take on the car, the car just ignored it an ran over the top of it but didn't cause any harm