The giant Laotian harvestman dwells inside the caves of Laos, and has a leg span stretching just over 330 millimeters (13 inches), thus making it the second largest harvestman discovered so far - surpassed only by another species in South America. It is currently unknown why it has such a large leg span, but it is believed that, since opiliones breathe[clarification needed] through their legs, a larger leg span makes respiration easier in the caves' low oxygen environment.