The biology of an aberrant saltioid spider,EuryattusThorell sp. indet., is described from observations in a Queensland rain forest and the laboratory. Pronounced morphological and behavioural changes occur during post‐embryological development. Juveniles spin webs, but adult females make ‘suspension nests’ by suspending a curled‐up leaf by heavy guylines from a rock ledge or vegetation. Adult males spin neither webs nor suspension nests. Females oviposit inside their suspension nests, but if denied access to leaves for suspension, they spin and oviposit in webs similar to those spun by juveniles. The flat, papery egg sacs ofEuryattusare atypical for a salticid, being more like the egg sacs of many of the Gnaphosidae. Intraspecific display behaviour has characteristics in common with typical salticids, but also includes unique features. Male courtship includes vibratory displays performed on the surface of the suspended leaf. Mating occurs inside the curled‐up leaf. Males co‐habit with sub‐adult females in suspension nests. Females take over suspension nests of other females and eat each other's eggs. Normal locomotion, intraspecific interactions, and predatory behaviour are characterized by frequent leaping.Euryattusroutinely makes long and accurate leaps on to prey, including flying insects intercepted in mid‐air and spiders and insects located in alien webs. The phylogenetic implications of the unusual characteristics ofEuryattu