The northern crab spider has many spiny hairs covering the top surfaces of the carapace, abdomen, and legs, and it has usually has greenish-yellow or yellow-brown markings (similar to those on the ridge-faced crab spider). There are a wide variety of possible color combinations, however. They can be very hard even for specialists to identify with certainty.
Like other crab spiders, they generally resemble crabs: Their legs extend outward from the sides, and they can walk in any direction. Learn more about the northern crab spider and other foliage flower spiders in their group page.