Web-spinners look a little like earwigs or termites, with small eyes, thread-like antennae and long bodies. Unlike earwigs, the tail structures are soft and jointed, and the wings are darker than those of termites. The head is broad and carries biting jaws.
Several invasive insect species have become established in Texas. Some of these species include red-imported fire ants, argentine ants and Formosan subterranean termites. One little known invasive insect species in Texas, Oligotoma nigra, originates from India, and it is considered a nuisance pest in urban and suburban areas of the state due to their attraction to artificial light sources, such as porch lights and street lights. This species is commonly known as the “black webspinner” and residents will most likely encounter males only, as females are not capable of flight. When these insects are not swarming in large numbers around porch lights they spend most of their time within their underground nests where they remain hidden from humans.
Black webspinners are around ‘35 of an inch in length with a dark brown to black exterior. While black webspinners are not considered an ecological threat in the US, they do consume non-vascular plants, such as moss and lichen, and they may move into yards in order to feed on dead plant matter. Recent research has revealed that black webspinners also feed on grasses and ornamental plants.
Webspinners dwell in below ground nests where colonies construct tunnels coated with silk that the insects produce from specialized organs. Webspinners spend most of their lifespan below the ground in order to avoid predators. These insects have adapted to their underground habitat by developing particularly muscular hind legs that allow them to move backwards rapidly within narrow underground tunnels. Additional adaptations include thin elongated bodies, and males possess oval-shaped wings that allow for unobstructed underground tunnel movement.
There is no way to determine with certainty as to how non-native black webspinners arrived in Texas, but experts believe that this invasive pest species arrived in the state via a shipment of date palms imported from Egypt. Black webspinners are distributed throughout the Southwest, and controlling nuisance swarms around homes is often unnecessary, as most residents in areas where these insects are abundant have become accustomed to waiting out swarms.