Brown Frogs

''Rana'' is a genus of frogs commonly known as the Holarctic true frogs, pond frogs or brown frogs. Members of this genus are found through much of Eurasia and western North America. Many other genera were formerly included here.
These true frogs are usually largish species characterized by their slim waists and wrinkled skin; many have thin ridges running along their backs, but they generally lack "warts" as in typical toads. They are excellent jumpers due to their long, slender legs. The typical webbing found on their hind feet allows for easy movement through water. Coloration is mostly greens and browns above, with darker and yellowish spots.

Distribution and habitat

Many frogs in this genus breed in early spring, although subtropical and tropical species may breed throughout the year. Males of most of the species are known to call, but a few species are thought to be voiceless. Females lay eggs in rafts or large, globular clusters, and can produce up to 20,000 at one time.

Diet

''Rana'' species feed mainly on insects and invertebrates, but swallow anything they can fit into their mouths, including small vertebrates. Among their predators are egrets, crocodiles, and snakes.

Systematics

Some 50 to 100 extant species are now placed in this genus by various authors; many other species formerly placed in ''Rana'' are now placed elsewhere. Frost restricted ''Rana'' to the Old World true frogs and the Eurasian brown and pond frogs of the common frog ''R. temporaria'' group, although other authors disagreed with this arrangement. In 2016, a consortium of ''Rana'' researchers from throughout Europe, Asia, and North America revised the group, and reported that the arrangement of Frost (2006) resulted in nonmonophyletic groups. Yuan et al. (2016) included all the North American ranids within ''Rana'', and used subgenera for the well-differentiated species groups within ''Rana''. Both of these classifications are presented below.

Genera recently split from ''Rana'' are '' Babina'', ''Clinotarsus'' (including ''Nasirana''), ''Glandirana'', '' Hydrophylax'', ''Hylarana'', '' Lithobates'', ''Odorrana'' (including ''Wurana''), ''Pelophylax'', ''Pulchrana'', ''Sanguirana'', and ''Sylvirana''. Of these, ''Odorrana'' and ''Lithobates'' are so closely related to ''Rana'' proper, they could conceivably be included here once again. The others seem to be far more distant relatives, in particular ''Pelophylax''.

New species are still being described in some numbers. A number of extinct species are in the genus, including ''Rana basaltica'', from Miocene deposits in China.

Species

The following species are recognised in the genus ''Rana'':

* ''Rana amurensis'' (Boulenger, 1886) – Siberian tree frog, Siberian wood frog, Amur brown frog
* ''Rana arvalis'' – Moor frog
* ''Rana asiatica'' – Central Asiatic frog, Asian frog
* ''Rana aurora'' – Northern red-legged frog
* ''Rana boylii'' – Foothill yellow-legged frog
* '' Rana cascadae'' – Cascades frog
* ''Rana chaochiaoensis'' – Chaochiao frog
* ''Rana chensinensis'' – Asiatic grass frog, Chinese brown frog
* '' Rana chevronta'' – Chevron-spotted brown frog
* ''Rana coreana'' – Korean brown frog
* ''Rana dalmatina'' – Agile frog
* ''Rana draytonii'' – California red-legged frog
* '' Rana dybowskii'' – Dybowski's frog
* ''Rana graeca'' – Greek stream frog, Greek frog
* ''Rana hanluica''
* '' Rana huanrenensis'' – Huanren frog
* ''Rana iberica'' – Iberian frog
* '' Rana italica'' – Italian stream frog
* ''Rana japonica'' – Japanese brown frog
* ''Rana jiemuxiensis'' – Jiemuxi brown frog
* '' Rana johnsi'' – Johns' groove-toed frog
* ''Rana kobai'' – Ryukyu brown frog
* ''Rana kukunoris'' – Plateau brown frog
* ''Rana latastei'' – Italian agile frog, Lataste's frog
* '' Rana longicrus'' – Taipa frog
* '' Rana luanchuanensis''
* '' Rana luteiventris'' – Columbia spotted frog
* '' Rana macrocnemis'' – Long-legged wood frog, Caucasus frog, Turkish frog, Brusa frog
* ''Rana maoershanensis''
* ''Rana muscosa'' – Southern mountain yellow-legged frog
* '' Rana neba''
* ''Rana omeimontis'' – Omei brown frog, Omei wood frog
* '' Rana ornativentris'' – Montane brown frog, Nikkō frog
* '' Rana pirica'' – Hokkaidō frog
* ''Rana pretiosa'' – Oregon spotted frog
* '' Rana pseudodalmatina''
* †'' Rana pueyoi''
* '' Rana pyrenaica'' – Pyrenean frog, Pyrenees frog
* '' Rana sakuraii'' – Stream brown frog, Napparagawa frog
* ''Rana sauteri'' – Sauter's brown frog, Kanshirei village frog, Taiwan groove-toed frog, Taiwan pseudotorrent frog
* '' Rana sangzhiensis'' – Sangzhi frog, Sangzhi groove-toed frog
* '' Rana shuchinae'' – Sichuan frog
* ''Rana sierrae'' – Sierra Nevada yellow-legged frog, Sierra Nevada Mountain yellow-legged frog
* '' Rana tagoi'' – Tago's brown frog
* ''Rana tavasensis'' – Tavas frog
* ''Rana temporaria'' – Common frog, European common frog, European common brown frog, European grass frog
* ''Rana tsushimensis'' – Tsushima brown frog, Tsushima leopard frog
* '' Rana uenoi''
* '' Rana ulma'' – Okinawa frog
* ''Rana zhengi''
* '' Rana zhenhaiensis'' – Zhenhai brown frog

Alternative classifications

AmphibiaWeb includes the following species, arranged in subgenera:

Subgenus ''Amerana'' (Pacific brown frogs)
* ''Rana aurora'' – northern red-legged frog
* ''Rana boylii'' – foothill yellow-legged frog
* ''Rana cascadae'' – Cascades frog
* ''Rana draytonii'' – California red-legged frog
* ''Rana luteiventris'' – Columbia spotted frog
* ''Rana muscosa'' – southern mountain yellow-legged frog
* ''Rana pretiosa'' – Oregon spotted frog
* ''Rana sierrae'' – Sierra Nevada yellow-legged frog, Sierra Nevada Mountain yellow-legged frog

Subgenus ''Aquarana'' (North American water frogs)
* '' Rana catesbeiana'' Shaw, 1802 – American bullfrog
* '' Rana clamitans'' Latreille, 1801 – green frog, bronze frog, northern green frog
* '' Rana grylio'' Stejneger, 1901 – pig frog
* '' Rana heckscheri'' Wright, 1924 – river frog
* '' Rana okaloosae'' Moler, 1985 – Florida bog frog
* '' Rana septentrionalis'' Baird, 1854 – mink frog
* '' Rana virgatipes'' Cope, 1891 – carpenter frog

Subgenus ''Lithobates'' (neotropical true frogs)
* '' Rana bwana'' Hillis and de Sá, 1988 – Rio Chipillico frog
* '' Rana juliani'' Hillis and de Sá, 1988 – Maya Mountains frog
* ''Rana maculata'' Brocchi, 1877
* ''Rana palmipes'' Spix, 1824 – Amazon River frog
* '' Rana vaillanti'' Brocchi, 1877 – Vaillant's frog
* '' Rana vibicaria'' (Cope, 1894)
* ''Rana warszewitschii'' Schmidt, 1857

Subgenus ''Liuhurana''
* '' Rana shuchinae'' Liu, 1950

Subgenus ''Pantherana'' (leopard, pickerel and gopher frogs)
* '' Rana areolata'' Baird and Girard, 1852 – crawfish frog
* '' Rana berlandieri'' Baird, 1859 – Rio Grande leopard frog
* '' Rana blairi'' Mecham ''et al''., 1973 – plains leopard frog
* '' Rana brownorum'' Sanders, 1973 – Gulf Coast leopard frog
* ''Rana capito'' LeConte, 1855 – Carolina gopher frog
* ''Rana chichicuahutla'' Cuellar, Méndez-De La Cruz, and Villagrán-Santa Cruz, 1996
* ''Rana chiricahuensis'' Platz and Mecham, 1979 – Chiricahua leopard frog
* '' Rana dunni'' Zweifel, 1957 – Lake Patzcuaro frog
* ''Rana fisheri'' Stejneger, 1893 – Mogollon Rim leopard frog
* ''Rana forreri'' (Boulenger, 1883) – Forrer's leopard frog
* '' Rana kauffeldi'' Feinberg et al., 2014 – Atlantic Coast leopard frog
* ''Rana lemosespinali'' Smith and Chiszar, 2003
* '' Rana lenca'' (Luque-Montes ''et al''., 2018)
* ''Rana macroglossa'' Brocchi, 1877
* ''Rana magnaocularis ...