Arid-ecosystems
Guides
Efferia
Hammertails
Efferia is one of the most species-rich genera of robber flies (family Asilidae), comprising approximately 241 recognized species distributed primarily across the Neotropical and Nearctic regions. These medium to large predatory flies (10–40 mm) exhibit exceptional diversity in arid and semi-arid ecosystems of the New World, with particularly high abundance in desert and grassland habitats. The genus is distinguished by pronounced sexual dimorphism in abdominal morphology and is notable for the males' distinctive 'helicopter tail' genital structure.
Eremobates
sun spiders, camel spiders, wind scorpions
Eremobates is a genus of solifuges (sun spiders/camel spiders) in the family Eremobatidae, distributed primarily in western North America. These fast-moving arachnids are notable for having the largest jaw-to-body ratio of any animal. They are non-venomous predators that rely on powerful chelicerae to subdue prey. Most species are nocturnal and navigate primarily using their pedipalps rather than vision. The genus contains approximately 97 accepted species.