There are astoundingly around twenty Mantis species in the US. Two in the genus Tenodera (the Chinese and the Narrow-winged) and one in the genus Mantis (the European Mantis) were introduced to the US but are now widespread. All are in the family Mantidae except a small Florida creature by the name of Mantoidea. (Here is a key to the Florida species including the Mantoidea.)

 http://entnemdept.ifas.ufl.edu/choate/mantid_key2_03.pdf

Most people just assume there is one "Praying Mantis." Maybe because they all look like they are praying. This gal above with the short wing covers I believe is the brown form of Stigmomantis carolina, the Carolina Mantis. There are five Stigmomantis species in the US but several are regional. This was a big girl, over four inches long. Generally considered beneficial predators in yards and gardens, they eat virtually anything and each other. You can even purchase egg capsules on the internet and hatch your own for your garden.

Another Carolina. This one was haunting a huge sunflower head my daughter grew in the yard. Mantises are very local and tend to live their entire lives on one bush, tree or garden plot.

This is a very young mantid from the Big Bend region. Can't verify which species it is but damn it is cute.