There are over 3000 species in this family of orb spider. They are identified by a large golf ball shaped abdomen or brightly colored oval abdomen except for the Micrathena and Gastercantha species, which do not fit this typical look but are equally easily identified by their unique shapes (tending to look like seeds for camouflage.
Within the family Araneidae is the subgrouping Argiopes, which are known for adding a specialized zig-zag pattern to the center of their webs. Although the reason for this is unknown, it is speculated that this both deters predators by making the spider look larger and enhances the capture rate of the web by adding more sticky surface area.
Nephilidae – Golden Orb Spiders
These 75 species used to be part of the Araneidae family but due to their large size, the golden hue of their silk, female reproductive plug and the unique behavior of the male after mating they were moved into their own subgroup. These spiders are the largest of the orb weavers and reach sizes up to two inches (five centimeters) across in the abdomen region. They often weave webs of over two feet across and are the most common “garden spiders" in the United States.
Males, instead of wandering off to die after mating, stand guard to deter other males from trying to mate with the female. Another unique Nephilidae aspect is that females have a plug that blocks secondary insemination so that once her eggs are fertilized a second male will not be able to mate with her.
Tetragnathidae - Long Jawed Orb Weavers
This particular sub family consists of spiders with exceptionally long jaws. They spin smaller webs than their cousins and do not fit them with signal lines or avenues of retreat. These spiders don’t spin tightly woven webs but use only a few radials and interior circles to catch their favorite prey, moths and butterflies. They also prey on mosquitoes and dragonflies near their chosen wetland habitat.
Uloboridae – Cribellate Orb Weavers
These spiders are both non-venomous and produce non-sticky filament silk. They rely on the tight weave of their webs to snare flying insects by using the prey’s own momentum to draw the web in around them.
Orb Weavers that Don’t build Webs
Bolas spiders create a small globule of web and cast it out like a fishing net to snare flying insects. They are often referred to as angler or fisher spiders. They initially attract the prey by using pheromones that mimic the mating scents of female moths. When the prey is within range, the globule net is launched with deadly accuracy.