The genus Holasteron was described by Barbara Baehr in 2004 for a number of Zodariid species across Australia. The name comes from Greek holo-, entire, all; as this genus of the Asteron-complex is found in all states of Australia except the Northern Territory. H. spinosum is the largest of its and easily recognised by the 4 strong spines at the end of the male palp. The carapace, sternum and chelicerae are sepia brown. Abdomen sepia brown on top with 2 pairs of white spots on top and 1 spot in front of the spinnerets and 2 elongate white patches on the flanks. The abdomen of females can be twice normal size when she is carrying eggs. Found in Western Australia, South Australia and north Victoria in open Acacia woodland.