It can just be a red back spider...
Have seen a very small spider with 4 white dots and 1 red dot. Not a red back. Ta ~Snaff
yes it means the poisonous spider
A black spider with a red back and thick fuzzy legs is commonly called a jumping spider. The formal name is Phiddipus audax.
a wolf spider. they hurt but are not deadly to humans
A spider.
Redback Spider is indigenous to Australia. It is a venomous spider.
The spider that is black with a white crescent on its back is the Brown House Spider. This spider is often confused with the red-back spider.
The Red Back Spider and the Funnel Web Spider (sometimes called the Sydney Funnel Web spider) are Australia's two poisonous spiders.
a red back.
red back spider
A black widow spider is black with a red mark on it's abdomen; this might or might not be what you meant. The black widow sometimes has a red mark on her back, as well. The red backed spider of Australia, a relative of the black widow, has an orange red mark on the back.
a spider.