These sizeable spiders are hunters that feed on cave weta (Gymnoplectron spp.), large grasshopper-like insects (4). Secured to the wall or ceiling via a drag line, the spider locates its prey and then drops down on top of it, before whisking it away in its grasp (4).
The Nelson cave spider produces large, almost spherical egg sacs that it suspends from the cave ceiling on silk threads (2) (4). Apparently long-lived, these spiders take three to five years to reach mature size, and have a low reproductive rate (5).