Zodariidae - (presumably) Storena species 3

Click image to enlarge

Zodariidae - (presumably) Storena sp. 3

These photos show the ant mimicry of this spider, which I presume is another Storena species, but such a large number of species from the Zodariidae family with its 19 genera, detailed information is required that is normally only available from specialised taxonomic journals, so without access to these, I shall allow myself a little wriggle room. Therefore, assuming this particular spider is from the genus Storena, it is one of the smaller species, being much less than 1 cm and closer to 1/2 cm (1/4") in length (excluding legs).

Two of the above photos show the female with her two front legs raised at an angle above her head to represent the ants antennae and she will keep them in that position until the need for deception is no longer required (which also included me taking photographs). Their more normal stance (shown in the other photos) is legs splayed and ready to run, which is typical of hunting ground spiders who ambush or run down their prey. Regarding this spider, their prey are often the very ants they pretend to be.

The patterning on their abdomen is quite different to those of Storena species 1, and apart from the considerable size difference, would alone indicate another species. The photographed male on the other hand, has the familiar boxing glove type pulps.

Zodariidae - (presumably) Storena species 2

Click image to enlarge

Zodariidae - (presumably) Storena sp. 2

As the Zodariidae family has 19 genera, plus coupled with my lack of taxonomic literature, I am reluctant to place this spider into Storena, although it closely resembles these spiders, except for the lack of spots on the abdomen. It has a couple of most unusual habits, one of which is to hold high one of its front legs, which is similar to a species in my previous post concerning Storena ( Spiders - Modern - Storena sp. 1 ). Secondly, it will stand on tip-toe, which I have not seen with other spiders. Why it should behave so, I can only speculate that it either wishes to appear larger, show off its body to deter or deceive, or as some sort of defensive stance. Whatever the reason it is very strange behaviour.

This spider which is a little over 1 cm (1/2") in length (excluding legs) also mimics ants by holding both its front legs at a low angle above its head to imitate the ants antennae. The size of the spider and the all black coloration brings to mind a local nocturnal broad-headed ant (shown on a Banksia flower), which may be the object of this Zodariidae mimicry. As with other members of this family, it does not build a web, but hunts it prey including the ants with whom it often mingles.

Zodariidae - Storena species

Click image to enlarge

Zodariidae - Storena sp.

The Zodariidae family has 19 genera and the Storena genus over 40 Australian species with 9 listed for Western Australia, so quite a large group. The spider shown here has a lot in common with Storena formosa that occurs in several States including WA, however I do not possess the information to accurately determine if it is. These spiders are distinctive by the front part of their carapace, which is near vertical, very high and looking like the spider is wearing a helmet. Many species, particularly the smaller black ones, hang around ants nests, with some being very good ant mimics.

These spiders do not construct webs (apart from the female building a silken retreat to brood her eggs), but actively hunt their prey on the ground and usually at night. During the day they conceal themselves under leaf-litter, logs and rocks and some species will even dig a burrow. However one the females above was encountered crossing a track on a bright sunny day at 11 o'clock in the morning. The bright orange markings probably served as a warning to predators that she was dangerous and to leave her alone, which the birds certainly did. It is not known how toxic the venom of these spiders are to humans, but with most spiders it is best to leave them alone, particularly if brightly colored.

The female above was close to 2 cm (3/4") in length excluding legs (one of the larger species), whilst the male was a little shorter but more than made up for the shortcoming by the length of its boxing glove like palps.