We found this praying mantis at Crescent Bay on the bunch grass that is drying out. We were surprised to see that cavity between its legs, with that white sac in it. We still don’t know for sure what it is, but we did learn something new: the praying mantis is the only animal with only one ear– and it is between the two sets of legs, close to the back legs.
The cavity we seem to see could just be stretched legs from the angle we looked at it as it hung upside down on the blade of grass because this cavity looks larger than the ear cavity we found on us mantis.com.
Anyway, the praying mantis can easily hear the chirps of the bats that are hunting it and thereby save itself from becoming lunch. See National Wildlife Federation.
If you have any other ideas, let us know!
I wonder, if I draw a line... 