found in Ocala national forest in FL. October 4th 2008. Started dropping out of the trees above when it was dark, well after dusk. Were coupled up as though they were mating. the larger bug was walking the other one was riding on its back. larger was approx 4″ smaller was only about 1.5″. They were very easy to kill/smush. when they died they lost their color and turned brown. They were not bothered by our presence at all. and when we tried to ‘scoot’ them away from our area with a paper plate they charged towards to plate.
You have seen the two-striped walkingstick, a common walkingstick in the southeastern US – from FL to TX. And as you suspected, it is a mating pair. The larger being the female. It has been noted that the male and female may attach to each other even before the female is mature…the male will hang on while the female molts.
One thing to be aware of is they can shoot a chemical spray that is irritating to the eyes. This ‘odiferous’ secretion is for defense and can be shot a foot or so with great accuracy.
The Univ of FL Entomology dept notes that the distinctive black and white striped walkingsticks of this species is only seen in the Ocala National Forest (this species seen elsewhere is brown with black stripes). They note, as you saw, the insect loses its distinctive white stripes once dead.
These insects feed on the leaves of trees and shrubs. The females are known to drop to the ground in the fall to lay their eggs in the sand.
What a great find!
Thanks for all the helpful information you provided also – it really helped with the identification.