Lichenmarked orbweaver


Number 119 ; June 17, 2015 ; Jeffrey K. Barnes


Lichenmarked orbweaver

Order: Araneae
Family: Araneidae
Genus and species: Araneus bicentenarius (McCook)


The orbweavers are spiders of the large family Araneidae. They are sedentary spiders readily recognized by their somewhat circular, spiral, wheel-shaped, silken webs. Insect prey snared in the lichenmarked orbweaversticky spiral silk lines are usually stunned by a bite from spider fangs and then wrapped, or mummified, in silk. Often the spider will consume the old web as evening approaches, rest for a time, then spin a new web in the same general location, thus keeping the web free of accumulating detritus.

The lichenmarked orbweaver occurs in the eastern North America from Nova Scotia and Minnesota south to northern Florida and Texas. It is a large spider, with females up to an inch in length, and it has a distinctive pastel green abdominal pattern and prominent bumps on the anterolateral margins of the abdomen. Its legs are distinctively ringed in dark and light colors. The base of all femora are orange, while the remainder of each leg has alternating black and white bands.

This species is considered to be somewhat rare. It is most often found in association with trees in wooded areas where it is superbly camouflaged among green-colored lichens. Reported prey include hornworms and adult dragonflies, but the lichenmarked orbweaver, like other orbweavers, is almost certainly a non-specialized predator, taking whatever happens into its snare. Scorpionflies have been known to steal food from its web.