Longitude W 117.8858718081394; Latitude N 33.65373347788835. � Peter J. Bryant. | Bolas spiderMastophora cornigeraAraneae: AraneidaeDuring the day, the female Bolas spider is inactive, although she can often be found in fairly exposed places. The male is much smaller than the female. The females provide a remarkable example of aggressive mimicry when they release chemicalssimilar to the sex attractants that are produced by female moths to attract males. They produce three chemicals that are identical to those produced by the moth. Thus, the main prey for these spiders is male moths. Stowe, Mark K., et al; "Chemical Mimicry: Bolas Spiders Emit Components of Moth Prey Species Sex Pheromones," Science, 236:964, 1987. Bolas spiders were featured on David Attenborough's TV series "Life in the Undergrowth" (2006).Back to Spider index page
Back to Arthropods of Orange County, California | Shortly after dusk, the spider lowers herself on silk threads, spins a silk line with a sticky blob on the end of it and swings it to catch the moths or other insects that have been attracted by the chemicals. The spider gets its name from the bolas (ball-on-a-string) weapon used by Eskimos and South American Indians. � Peter J. Bryant |
Here she has caught a cranefly. � Peter J. Bryant | Here she is hauling it in. � Peter J. Bryant |
Here she is sucking blood from her prey. � Peter J. Bryant | Here she has caught a moth, wrapped it in silk, and is feeding on it. � Peter J. Bryant |
The egg cases of this spider are round balls hanging on silk straps. When discovered, in November 2005 on a kiosk at the Peter and Mary Muth Interpretive Center at Upper Newport Bay, Newport Beach, California, this female had already made eight egg cases and hung them on a web. Two weeks later, another egg case had appeared! © Peter J. Bryant | 24 May 2006: Adult male just emerged. � Peter J. Bryant |