Net Casting Spider from Australia

Subject:  Four-legged Spider
Geographic location of the bug:  NSW, Australia
Date: 01/12/2018
Time: 07:19 PM EDT
Your letter to the bugman:  Hello Bugman,
Found a four-legged Spider at my fence. When I placed it in a dust pan to put outside it turned out it had 8 legs.
Is this harmful as well?
I keep seeing a lot of spiders lately.
How you want your letter signed:  Carlo

Net Casting Spider

Dear Carlo,
This is a Net Casting Spider in the family Deinopidae.  According to Atlas of Living Australia, they are reported from all over your continent.  According to Australian Museum:  “Net-casting Spiders have a unique way of catching their prey. They make a small web in the form of a net held by the front legs that can be stretched out wide to envelop an unwary insect passing by.”  That site further elaborates:  “Net-casting Spiders have stick-like bodies, with spindly legs. Members of the genus
Deinopis have a large, prominent pair of eyes at the front of the head (hence their other common name of Ogre-faced Spiders) and vary in colouring from fawn to pinkish brown or chocolate brown. Members of the genus Avella have smaller eyes and have subtle greenish brown to grey patterning. The males are smaller and even more slender and stick-like than the females, and can differ from them in their colour and patterning.”  Here is some additional information from Australian Museum:  “When at rest, the spider hangs from vegetation with its head downwards, its long body and long, thin front and back legs held together on each side, giving the spider a stick-like appearance. The spider also assumes a head-down position when it is waiting for prey, except that it now holds its net with the front four legs and suspends itself by the back legs and spinnerets from support lines to surrounding foliage. The net is a blueish-white square of wool-like cribellate silk, whose coiled lines are designed to stretch and entangle prey. In order to have an aiming point, the spider often drops splashes of white faecal droppings onto the leaf or bark substrate over which it is poised. When an insect walks across this ‘target’, the spider plunges its net downward to envelop and entangle it. If successful, the spider silk-wraps the prey item, bites and paralyses it, and then feeds on it. Net strikes will also be made at flying insects that stray too close. An unused net is sometimes stored by hanging it on nearby leaves for the next night’s hunting, or the spider may eat it.”

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