This species has a palearctic distribution. M. virescens is the only European representative of the family Sparassidae, that is actually native to the tropics. It occurs naturally in Northern and Central Europe, including Denmark.
In the females of Micrommata virescens the body length can reach 12–16 millimetres (0.47–0.63 in), while in the males it is about 7–10 millimetres (0.28–0.39 in).
The cephalothorax and the long legs of the females are bright green, with a lighter green abdomen showing a darker green median stripe. The eight eyes are arranged in two rows and surrounded by white hairs. Males are dark green-olive and have a narrower abdomen, with red sides and a red to red-brown median stripe bordered yellow. Young spiders have a yellow-brown cepahlothorax, with dark marginal and median stripes. Only after the last molting in the following spring the juveniles assume the typical coloration of the adults.
The green coloration is due to the bilin micromatabilin and its conjugates in haemolymph, interstitial tissues and the yolk of oocytes. A bite from this spider on a human may cause some local swelling and a little bit of pain, and would be gone within 2 days.