Sunday, July 25, 2010
This odd yet pretty little spider is a Spined Micrathena (Micrathena gracilis), they are very common in gardens and woodlands throughout Eastern North America. I see them all the time in my backyard flower gardens.....I easily have a dozen or more of these little females sitting in the middle of their simple yet effective web. These webs will measure approximately 30 cm (6 to 8 inches) in diameter. Like most spiders, only the female is responsible for web building. The males are capable of producing silk, but it used in mating rituals only. Males will carefully approach the web, and using his legs will tap out specific signals to the female on a specific piece of silk that he will use to attach to her web. If the female is feeling amorous, she will not eat him. Mating will occur and if he is quick enough he will live to see another day. The life of a male spider is truly a life lived on the edge. He is almost always at the mercy of the mood of his potential mate. The female will lay eggs in a sac woven of silk that will overwinter near the original location of the web; usually hidden in the bushes. It takes approximately one year for them to complete their lifecycle.
These are relatively small spiders; females measure up 1/2 of an inch in length, males are about half that size. They are a glossy black with white spiny abdomen, males will have no spines and will be lighter in color. There will be a total of 10 spines located around the perimeter of the abdomen.The spines on the abdomen are an adaptation that protects the spider from being eaten. They are quite sharp and can even draw blood if smashed against your skin. Any bird, frog, or other insect bent on munching on this spider would get a nasty surprise when the spines hit the palate. I would assume it would feel very much like munching on a cocklebur.
They mainly feed on flies and other small insects. Their web is too small to contain very large prey. Butterflies and large moths would most likely tear the web to pieces. While walking through the timber these are the most commonly encountered webs in this area. There is very little that is more discerning that walking into a web and not knowing if the spider has now taken up residence on your body somewhere. Makes me shiver to think about it!