About Sicarius thomisoides Walckenaer, 1847
Description and behavior: This species grows to a body length between 12 and 20 mm. It inhabits desert areas of northern and central Chile, and has nocturnal habits. In northern Chile, it builds shelters under rocks on sandy substrate, and it is extremely common in urban regions with large amounts of household waste. Members of the genus Sicarius have been observed feeding on insects, scorpions, and other spiders. However, in 2020, a 20 mm long Sicarius thomisoides specimen was recorded preying on a 28 mm long gecko (Phyllodactylus gerrhopygus) in Mamiña, northern Chile. The spider was observed feeding on fluids from the gecko's digested body. The gecko's skin was damaged and dark, which suggests possible dermonecrotic effects. This aligns with previous reports that Sicarius spiders produce enzymes with hemolytic and dermonecrotic activity, with an action similar to that of Loxosceles spiders.
