In the genus Selaginella, subgenus Tetragonostachys, there are five species that occur within Georgia.
Of these five species, four species grow as upright to sprawling plants. The fifth grows as a low growing spreading plant.
Selaginella acanthonota
http://www.flickr.com/photos/alan_cressler/2299743566/in/set-72157600029652522occurs from southern Florida westward into the Panhandle and northeasterly through eastern Georgia into southeastern
North Carolina. It occurs on sandy soils.
Selaginella arenicola
http://www.flickr.com/photos/alan_cressler/5314550735/in/set-72157600029652522occurs from southern Florida into eastern Georgia. It also occurs on sandy soils.
Selaginella corallina
http://www.flickr.com/photos/alan_cressler/3350896754/in/set-72157600029652522was formerly known as a subspecies of S. arenicola, as S. arenicola riddellii but was recently changed to species status.
It is the most widespread of any of the upright species occurring in the state and ranges from eastern Georgia into eastern Alabama and then jumps over to southwestern Arkansas and western Louisianna and spreads westward into southern
Oklahoma and into south central Texas. It is found on sandy to gravely soils and granitic outcrops.
Selaginella tortipila
http://www.flickr.com/photos/alan_cressler/3296106827/in/set-72157600029652522is the rarest of the species and is found only on granitic boulders and soils of the Blue Ridge Mountains. Its ranges is from extreme northeastern Georgia into eastern North Carolina.
Selaginella rupestris
http://www.flickr.com/photos/alan_cressler/2956610218/in/set-72157600029652522is the most widespread species in the entire subgroup, occurring along the entire course of the Appalachians, in the heartland of the US from Minnesota southward into Oklahoma and as far west as eastern Wyoming. The species occurs
well into Canada even reaching the southwestern coasts of Greenland. It occurs on a variety of substrates that appear to be all rather well draining.