Is the red part of the black widow supposed to be on the top or bottom?

Question

i was researching black widow, but i thought that the red hourglass on the spider was supposed to be on the underside of the abdomen... but on some of the spiders shown, the hourglass mark can be seen on the top part on the abdomen...

Answer 1

Well, first there are 3 related species of spiders called the black widow, and there are several other close relatives that look similar.  

The tell-tale mark is always on the underside in the 3 widow species, the red widow, the Mediterranean widow, and the brown widow.  However, they often have red markings on their back side too, especially as a juvenile.

Also, color and patterns can vary within the same species, which is why trying to identify a spider with described color pattern is very, very hard.  

Here is a gallery of the black widow and it's relatives, arranged by species;

http://bugguide.net/node/view/1999/bgpag...

Additional details - Widow spiders like dark, low traffic places like sheds, garages, and outhouses (that is where most bites occurred.  With the invention of indoor plumbing BW bites went waay down).   Widow spiders and their relatives (31 species total) live worldwide outside of the arctic zones.

Answer 2

Help yourself -

http://www.spideridentification.org/

http://www.badspiderbites.com/spider-ide...

http://www.aboutbugsbugsbugs.com/spiders...

http://www.pesticide.org/spiders.html

Answer 3

The Black Widow Spiders (Latrodectus mactans) that live in the USA "always" have the red hourglass on the ventral surface of the abdomen (underside).  It is far easier to see on the female than the male, because the male is so tiny, about the size of a small grain of rice.

The Black Widow Spiders of Australia can have red markings (not an hourglass) on the dorsal (top) surface of the abdomen.  These are called Red-Back Spiders, and are every bit as venomous as the one in America.

Contrary to popular belief, Black Widow Spider bites are rarely fatal, even though once you've been bitten you'll wish you were dead because of the pain. Bites are also rare, because these beautiful animals live in dark, secretive places where they wait for their unsuspecting prey.  Females can live up to 5 years, and can rid the area of many pesky and harmful pests, like Cockroaches, other spiders, Crickets, flys, wasps, termites, gnats, and many others.

The web of these fascinating spiders is not a beautiful, symmetric thing like that of the Orb Weaver Spiders, but more of a mass of irregular webbing.

After mating the female does NOT always kill and eat the male.  But, sometimes he does "something" wrong and she wraps him up, and sucks out his body fluids to supply herself with the energy needed to lay the upcoming eggs in her large, white egg sac.

Black Widow Spiders can live almost anywhere. In your attic, or your basement, or your garage, but normally they live in the forests or deserts among the plants.  As long as they have a source of water and it does not get too cold they will survive.

Answer 4

i think its on the top