Only when the riverbank wolf spider moves on the gravel banks of the Tyrolean Lech, it is easy to recognize. With their gray-brown coloration and contrasting markings, these spiders are very well camouflaged. They reach a considerable size. The females of the river wolf spider(Arctosa cinerea) grow to about 17 mm long, the males to about 14 mm. This makes them one of the largest native representatives of the wolf spider family.

To survive on the gravel banks of the Tyrolean Lech, the riverbank wolf spider has come up with a special trick. It digs living tubes in the sandy subsoil, which it pads with spider silk. It stays there during the day and goes hunting at night. If high water threatens, it closes the openings of its living tube. The water flows away over the cave. Meanwhile, the riverbank wolf spider can survive in the air bubble.