The genus Tadarida has 9 or more species of free-tailed bats divided into two subgenera, with the first of these containing seven species spread across the Old World (including southern Europe and North Africa, large parts of southern Asia, and India right across to Japan). Four species occur exclusively in Africa including Madagascar while two more species occur in central Papua New Guinea, and western and southern Australia, respectively.
The relatively well-known species T. teniotis, which occurs in southern Europe and North Africa, the Middle East and across southern Asia to Japan, is known to fly often during the late afternoon, where it will hawk for insects alongside swifts (Apodidae), swallows, and martins (Hirundinidae).
The other subgenus contains the widespread New World single species T. brasiliensis (subgenus Rhizomops), which ranges from the southern United States and the West Indies to Chile and Argentina. This species is noted for its massive maternity colonies in the United States, especially in the southwest, where an estimated population of over 25 million (possibly as high as 50 million) existed in Eagle Creek Cave in Arizona in the 1960s.
Molecular sequence data indicates Tadarida is not a monophyletic taxon. The closest relative of Tadarida aegyptiaca of Africa and southwest Asia is Chaerephon jobimena of Madagascar. These two species plus Tadarida brasiliensis of the Americas form a clade believed to be about 9.8 million years old.
The genus name "Tadarida" is attributed to the naturalist Constantine Samuel Rafinesque, who gave no clues to its etymology. It has been suggested that "Tadarida" comes from the Corsican word for bat, "Taddarita." 
Species list for genus:
- Tadarida aegyptiaca - Egyptian free-tailed bat
- Tadarida australis - white-striped free-tailed bat
- Tadarida brasiliensis (now in subgenus Rhizomops) - Mexican free-tailed bat or Brazilian free-tailed bat
- Tadarida fulminans - Madagascan large free-tailed bat
- Tadarida kuboriensis - New Guinea free-tailed bat
- Tadarida latouchei - La Touche's free-tailed bat
- Tadarida lobata - Kenyan big-eared free-tailed bat
- Tadarida plicata - Wrinkle-lipped free-tailed bat
- Tadarida teniotis European free-tailed bat syn. (Tadarida insignis)
- Tadarida ventralis - African giant free-tailed bat
- Simmons, Nancy B. (2005), "Chiroptera", in Wilson, Don E.; Reeder, DeeAnn M., Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed), Baltimore: Johns Hopkins University Press, pp. 312–529, ISBN 978-0-8018-8221-0, retrieved 29 September 2009
- Minnick, N. and P. Myers. 2006. "Tadarida australis" (On-line), Animal Diversity Web. Accessed October 22, 2006 at http://animaldiversity.ummz.umich.edu/site/accounts/information/Tadarida_australis.html.
- Lamb, J. M.; Ralph, T. M. C.; Naidoo, T.; Taylor, P. J.; Ratrimomanarivo, F.; Stanley, W. T.; Goodman, S. M. (June 2011). "Toward a Molecular Phylogeny for the Molossidae (Chiroptera) of the Afro-Malagasy Region". Acta Chiropterologica. 13 (1): 1–16. doi:10.3161/150811011X578589.
- Heidt, G. A., Elrod, D. A., & McDaniel, V. R. (1996). Biogeography of Arkansas mammals with notes on species of questionable status. Journal of the Arkansas Academy of Science, 50(1), 60-65.
- Riccucci, Marco (2015). "Derivation of the Generic Name Tadarida (Rafinesque, 1814)". Bat Research News.