Long-Bodied Cellar Spider | Pholcus phalangioides
The most common and widespread species is the long-bodied cellar spider, Pholcus phalangioides. Originally from Europe, the long-bodied cellar spider has been in the Americas for centuries. It has an elongate tannish-gray abdomen with no other markings. It also has a darkened pattern around the eyes that is frequently mistaken for the violin of a brown recluse, causing it to be misidentified, leading to unnecessary concern.
In the southwestern portion of the U.S., a Mediterranean species, the marbled cellar spider, Holocnemus pluchei, has become well established from the San Francisco Bay area, south to San Diego along the coast and east to Arizona. This spider also has an elongate abdomen with mottled coloration with a dark brown sternum and dark brown longitudinal stripe on its belly. From Florida to Texas, another cellar spider, Crossopriza lyoni, has become established and congregates around buildings in large enough numbers to elicit pest control measures. It has a truncated abdomen that looks like someone hacked off the posterior end.
As their name implies, cellar spiders, especially the long-bodied cellar spiders, are commonly found in the semi-subterranean basements of homes where they leave unsightly cobwebs in corners and by windows. The marbled cellar spider is commonly found under house eaves, in corners inside the house, and under outdoor porch overhangs. Their populations can result in dozens to more than 100 spiders inhabiting the outside of a single home. These spiders cause no appreciable damage, but they do make aesthetically unsightly webs.
Spraying the spider in the webs should result in control. Sweeping away old spider webs reinforces to the homeowner that the area has been treated. It also allows pest management professionals to reassess how well the treatment worked on subsequent visits. One useful aspect about controlling cellar spiders is that they carry their egg sac, with the eggs surrounded by a few strands of silk, in their fangs. Therefore, vacuuming spiders carrying eggs will also eliminate a portion of the next generation.