Those who are deftly afraid of spiders should avoid buying a home in Houston, as the most dangerous spider species in North America are abundant in the city. Medical literature mentions brown recluse and black widow spiders as being the only “medically significant” spiders in the US, but this claim is a bit misleading for a few reasons. For one thing, there are a total of five “widow” spider species in the country, which is the common name for spider species in the Latrodectus genus. Also, a total of 13 recluse spider species have been documented in the US, two of which are non-native. “Recluse” is the common name for spider species in the Loxosceles genus, the native brown recluse being the most common and the only one known to prefer dwelling in close association with humans. Unfortunately, the brown recluse and southern black widow spider species both inhabit Houston where they frequently appear within homes.
In addition to the southern black widow (Latrodectus mactans) and the brown recluse (Loxosceles reclusa), the recently introduced brown widow spider (Latrodectus geometricus) has become abundant in urban areas along the Gulf Coast, including Houston. The Texas recluse (L. devia) may be encountered in Houston on rare occasions, but this species is not associated with urban settings, and they are most abundant in southern Texas. Yet another recluse spider species known as the Mediterranean recluse (L. rufescens) is a non-native species that has become well established along the Gulf Coast, and they have been spotted in Houston several times. Much like the brown recluse, the Mediterranean recluse is an urban dwelling spider that is widely considered to be one of the most invasive spider species in the world, as they are in the habit of hitchhiking to new areas in cargo shipments that contain household goods, such as furniture and electronics. Currently, the southern black widow, the brown widow, the brown recluse, and to a lesser extent, the Mediterranean recluse, are the only medically significant spider species that are commonly found within Houston homes, sometimes in large numbers. Although all four of these highly venomous spiders are among the top ten most commonly controlled spider species within US homes, they are generally shy and reluctant to bite humans.
Have you ever encountered a recluse spider species within your home?