Most spiders are predators , but the jumping spider Bagheera kiplingi gets over 90 % of its food from fairly solid plant material produced by acacias as part of a beneficial relationship with a species of ant . Although spiders are generally regarded as predatory , the jumping spider Bagheera kiplingi gets over 90 % of its food from fairly solid plant material produced by acacias as part of a mutually beneficial relationship with a species of ant .