Ophioglossum engelmannii, commonly known as the limestone adder's-tongue,[1] is a species of fern native to the Western Hemisphere. It is widespread and native to the United States, Mexico, and Central America.[1] Its primary natural habitat is dry barrens and glades in calcareous areas.[2]
It is a small species that produces leaves in the spring and dies back in the summer. A second growth of leaves is sometimes produced with the fall rains.[3]