Sunday, April 19, 2015
Northern False Widow
There are a few spiders in the genus Steatoda which possess venom capable of causing medically significant responses in humans, but most do not. The majority of people who may be bitten by one of these spiders would not experience any reaction at all. Like all spiders they have venom which is used to subdue prey, it is not designed to cause harm to human tissue, but if you are allergic to the proteins in the venom a very serious reaction may occur.
This species has a dark brown body, and a lighter brownish-red abdomen with a yellow or cream color "T" marking. The underside of the abdomen is much lighter than the top.
Reaching lengths up to 7 mm, females are larger than males, as is the case with most spiders. Females construct messy webs that males will tap on to signal to the female that he is nearby and interested in mating. The male will tap on the web in a specific little dance that hopefully the female will find enticing in terms of mating and not dining. If she is not in the mood for mating, she will capture him and treat him like any other unfortunate arthropod that finds itself in her web. However if she is receptive mating will occur. After mating, the female will form two or more egg sacs that she places at the edge of her web and will guard. Egg sacs hatch in the fall when many dozens of spiderlings will disperse into the environment. Some females will overwinter if the weather is warm enough or if they are able to find a sheltered area.
These spider will often build their webs in the corners of our homes, especially in cellars and basements, as well as outside under logs, rocks or other debris. Like all spiders they are beneficial because of their preference for many insects that may become pests like flies and certain species of moths.