Araneus saevus is a northern species found from Canada into the northern United States. It is often confused with other large, dark orbweavers such as A. nordmanni.
A. saevus is a large dark-brown to black species with conspicuous dorsal humps on the lateral anterior abdomen. The humps may be lighter in color than the other areas. The abdomen is generally very dark brown and has a dorsal black folium. Between the abdominal humps there is a stripe of white or cream of varying length/width depending on the specimen at hand. The underside of the abdomen has two white spots located opposite each other. Females are 11 to 21 millimeters long, and males are 9 to 14 millimeters in length and darker than females.
Little information is available on the life history of this species, but it undoubtedly overwinters in the egg stage with adults found from mid-summer to mid-autumn. Most often found in forested locations on a variety of trees, it can also be seen in suburbia that is landscaped with mature plantings.
Most orbweavers either scurry to a silken retreat or drop to the ground when disturbed. There is one recorded, verified case of the fierce orbweaver bite causing pain, swelling, fever, and numbness.
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Authored by: Steve Jacobs, Sr. Extension Associate