True frogs is thecommon name for thefrogfamilyRanidae. They have the widest distribution of any frog family. They are abundant throughout most of the world, occurring on allcontinents except Antarctica. The true frogs are present in North America, northern South America, Europe, Africa (includingMadagascar), and Asia. The Asian range extends across theEast Indies toNew Guinea and a single species, theAustralian wood frog (Hylarana daemelii), has spread into the far north of Australia.
Typically, true frogs are smooth and moist-skinned, with large, powerful legs and extensively webbed feet. The true frogs vary greatly in size, ranging from small—such as thewood frog (Lithobates sylvatica)—to large.
Many of the true frogs are aquatic or live close to water. Most species lay their eggs in the water and go through a tadpole stage. However, as in most families of frogs, there is large variation ofhabitat within the family. There are also arboreal species of true frogs, and the family includes some of the very fewamphibians that can live inbrackish water.[1]
The Ranidae are related to several other frog families that haveEurasian andIndian origins, includingRhacophoridae,Dicroglossidae,Nyctibatrachidae,Micrixalidae, andRanixalidae. They are thought to be most closely related to the Indian-endemic Nyctibatrachidae, from which they diverged in the earlyEocene. However, other studies recover a closer relationship with the Dicroglossidae.[2][3]
It was previously thought that the Ranidae and their closest relatives were ofGondwanan origins, having evolved onInsular India during theCretaceous. They were then entirely restricted to theIndian subcontinent until the lateEocene, whenIndia collided with Asia, allowing the Ranidae to colonize Eurasia and eventually the rest of the world.[3] However, more recent studies instead propose that the Ranidae originated in Eurasia, and their close relationship with India-endemic frog lineages is due to those lineages colonizing India from Eurasia during thePaleogene.[2][4]
The subdivisions of the Ranidae are still a matter of dispute, although most are coming to an agreement. Several formersubfamilies are now recognised as separate families (Petropedetidae,Cacosterninae,Mantellidae, andDicroglossidae). The genusRana has now been split up and is much reduced in size.
While too little of the vast diversity of true frogs has been subject to recent studies to say something definite, as of mid-2008, studies are going on, and several lineages are recognizable.[5][6][7]
The genusStaurois is probably a very ancient offshoot of the mainRaninae lineage.
Most of the subfamilies formerly included under Ranidae are now treated as separate families, leaving only Raninae remaining. The following genera are recognised in the family Ranidae:[10]
AbavoranaOliver, Prendini, Kraus, and Raxworthy, 2015 (three species)
^Cai, Hong-xia; Che, Jing; Pang, Jun-feng;Zhao, Er-mi; Zhang, Ya-ping (2007): Paraphyly of ChineseAmolops (Anura, Ranidae) and phylogenetic position of the rare Chinese frog,Amolops tormotus.Zootaxa1531: 49–55.PDF fulltext
^Kotaki, Manabu; Kurabayashi, Atsushi;Matsui, Masafumi; Khonsue, Wichase; Djong, Tjong Hon; Tandon, Manuj; Sumida, Masayuki (2008): Genetic Divergences and Phylogenetic Relationships Among theFejervarya limnocharis Complex in Thailand and Neighboring Countries Revealed by Mitochondrial and Nuclear Genes.Zool. Sci.25 (4): 381–390.doi:10.2108/zsj.25.381 (HTML abstract)
^Amphibian Species of the World 5.5, an Online Reference."Hylarana Tschudi, 1838". American Museum of Natural History.{{cite web}}: CS1 maint: numeric names: authors list (link)
Frost, Darrel R. (2006): Amphibian Species of the World Version 3 -Petropedetidae Noble, 1931. American Museum of Natural History, New York, USA. Retrieved 2006-AUG-05.
Frost, Darrel R. et al. (2006): The amphibian tree of life. Bulletin of the American Museum of Natural History. Number 297. New York.
Pauly, Greg B.; Hillis, David M.;Cannatella, David C. (2009): Taxonomic freedom and the role of official lists of species names.Herpetologica65: 115–128.
Rafinesque, C.S. (2007): "Fine del prodromo d'erpetologia siciliana ".Specchio delle Scienze, o, Giornale Enciclopedico di Sicilia2: 102–104. (Ranidae, new family). (inItalian).
.jpg)
