Venom of a six-eyed crab spider, Sicarius testaceus (Purcell, 1908), causes necrotic and haemorrhagic lesions in the rabbit

By employing haematological, histological and isotope studies on rabbit, it was shown that envenomation by the South African crab spider, Sicarius testaceus, results in tissue necrosis and a marked increase in the permeability of the blood vessels in the vicinity of envenomation. The venom also acts systemically, which results in petechial bleeding of some viscera, thrombocytopaenia and elevated fibrinogen levels. Rabbit envenomation by this species results in a dramatic drop of the platelet count, without haemolytic anaemia. Should these parameters be the same in humans, they may serve as a yardstick to distinguish presumptive S. testaceus envenomation from that of Loxosceles.