beetle discovered 6.19.2016
That is a giant mesquite bug nymph. They are typically found on mesquite trees where they feed on the sap. They don't do any significant damage to the trees so they are not considered to be a pest.
Thank you for the response to the beetle
I should have mentioned earlier that it is not a beetle but rather a different type of insect called a true bug of the order Hemiptera. It's a distinction that many people don't worry about but since I am an entomologist, I had to let you know or I wouldn't be able to sleep at night.
Peter...thanks for the correction!