pugsly said:
Redbacks were'nt but Black Widows are American so they probably were.
Closely related species, once thought to be subspecies but now all elevated to species level.
Lactrodectus mactans is the Black Widow, range - Nth America. Most popularly identified as being black with a red hourglass on it's underside just anterior to the spinnarets.
Lactrodectus hasseltii is the Australian Redback, so named because of the broad redstripe down the middle of it's back.
Latrodectus tridecimguttatus, the Malmignatte or 13-spotted Spider. Found in Southern Russia, Ukraine. Black with 13 pale spots over the body.
Latrodectus katipo, the Katipo. Found in New Zealand. Interestingly, the Katipo's habitat is beaches.
Latrodectus atritus, the Black Katipo, also found in NZ. Both species are endangered and the subject of management plans.
I can't talk about the variation in the non-Australian species, but I am familiar with the Redback. They come in many different colours. I've heard there are some with greenish and yellow stripes. I've seen some with white stripes. Some come with no stripes at all (i.e. all black). Others come with spots.
Many come with the red hourglass. In fact, I was looking at one today - big red stripe and the hourglass. I found one years ago with just the hourglass and, thinking it was a Black Widow, took it into the Museum to Dr Mike Gray who told me it was actually a Redback but looked like a Widow.
The reason I bring all this up is because, as far as I'm aware, there are no Black Widows in Australia, just Redback lookalikes.
Interestingly, one theory that has been suggested is that the Redback itself is introduced from some Pacific Islands, arriving here in the 1800's.
Hix