LEPTODACTYLIDAE AMERICAN POND FROGS FAUNA PARAGUAY

LEPTODACTYLIDAE - THIN-TOED FROGS

Fourteen species recorded in Paraguay, all belonging to the same genus and classified in the subfamily Leptodactylinae Werner, 1896. The Leptodactylids bear the same basic shape as the Ranidae of Europe and are ecological equivalents in much of South America, though anatomically they are closer to tree-frogs. Leptodactylids are medium to large, terrestrial and semi-aquatic frogs. They exhibit 8 free procoelous, holochordal presacral vertebrae. Ribs are absent. The urostyle is free with two condyles and the pectoral girdle arciferal. They have bony elements in the sternum and the omosternum is present. The clavicle does not overlie the scapular. Palatines are present. Teeth present on the maxilla and premaxilla, those on the former being pedicellate. Astralagus and calcaneum are fused only at the ends. No intercalary phalanges. The sartorius is a separate and distinct muscle. Pupil usually horizontal. Build foam nests. Larvae aquatic or, more rarely, terrestrial. 2n=18, 20, 22 or 26. Sperm with two tail filaments.

REFERENCES
Caramaschi U, de Sá O, Heyer WR 2005 - Common Names for the Frog Genus Leptodactylus (Amphibia, Anura, Leptodactylidae) - Herpetological Review 36: p119-120.
Cei JM 1980 - Amphibians of Argentina - Monitore Zoologico Italiano Monografia 2.
Fouquette MJ (undated) - Synopsis of Recent Amphibians to Genus - Arizona University.
Whitfield P Ed.1984 - Longman Illustrated Animal Encyclopedia - Guild Publishing, London.

Key to Adults of Paraguayan Thin-toed Frogs

1a Dorsum creamy-white with shiny red blotches, thinly bordered black. Chaco only ........ Leptodactylus laticeps
1b Not as above ............................................................................................................................................... 2

2a Longitudinal dorsal glandular folds present. Dorsolateral and lateral folds present or absent. ...................... 3
2b Longitudinal dorsal glandular folds absent. Dorsolateral and lateral folds present or absent. ...................... 7

3a Large frogs with 8 to 10 longitudinal glandular folds on dorsal surface. Snout rounded and barely protruding beyond jaw......................................................................................................................................................... 4
3b Small to medium-sized frogs with 6 prominent and 5 faint longitudinal glandular folds on dorsal surface. Snout pointed and clearly protruding beyond jaw. ............................................................................................ 5

4a Patternation indistinct, with spots and blotches inconspicuous even on legs. Belly immaculate. Posterior side of thigh dull green. Two lateral longitudinal glandular folds typically distinctly paler than the others, giving a "lined" appearance to the dorsum. .................................................................................... Leptodactylus chaquensis
4b Patternation bold and conspicuous, with large blotches and dorsal surface and spots on legs broadly pale-edged. Belly marbled with grey. Posterior side of thigh green with paler marbling. Lacks pale longitudinal lines on the dorsum. ...................................................................................................................... Leptodactylus latrans

5a Slender and long-legged. Dorsal surface clearly longitudinally striped and indistinctly spotted. Broad pale vertebral stripe present. ................................................................................................................................. 6
5b Dumpy and short-legged. Dorsal surface boldly spotted but not striped. Broad pale vertebral stripe typically absent (rarely present). .......................................................................................................... Leptodactylus fuscus

6a Dorsal surface of thigh with thin yellowish longitudinal lines. Posterior surface of thigh with leopardskin pattern. SVL up to 50mm. ....................................................................................................... Leptodactylus gracilis
6b Dorsal surface of thigh without thin yellowish longitudinal lines. Posterior surface of thigh with variably distinct, light horizontal stripes. SVL <45mm. .................................................................... Leptodactylus furnarius

7a Bold "moustached" head pattern with black band to the eye and white band on across upper lip. One or sometimes two dorso-lateral folds. .................................................................................................................... 8
7b Not as above ................................................................................................................................................ 9

8a Broad black dorso-lateral bands and clear patternation of black spots and lines on flanks. No light stripe on posterior surface of thigh. Snout only moderately protruding and somewhat blunt. SVL 44-67mm. No interorbital bar ................................................................................................................... Leptodactylus mystacinus
8b Flanks typically greyish with a single light and/or dark line. Posterior surface of thigh with distinct light horizontal stripe. Snout long and somewhat pointed. SVL 38-49mm. Interorbital bar typically present. .................................................................................................................................................. Leptodactylus elenae

9a Medium-sized to enormous frogs (SVL >58mm). Males with keratinised spines on finger and sides of chest.................................................................................................................................................................. 10
9b Small to medium-sized frogs (SVL<65mm). No keratinised spines on finger and sides of chest. ................ 11

10a Enormous frog (SVL up to 200mm).. Dorsal skin smooth and uniformly brownish. Head very large, with short, rounded snout. Black-and-white vertical striped pattern on lips. Groin and thigh bright red. ........................................................................................................................................ Leptodactylus labyrinthicus
10b Large frog (SVL 58-90mm). Dorsal surface of back and legs usually wine red in colour, contrasting strongly with paler lateral skin. Known Paraguayan distribution localised and specialised, restricted to rocky hillsides east of the Paraguay River. ..................................................................................................... Leptodactylus syphax

11a Dorsal skin "toad-like" with discrete large warts. Snout sharpened or upturned in lateral view. ................ 12
11b Dorsal skin pustular and irregularly warty, or smooth. Snout rounded or slightly truncate in lateral view. .. 13

12a Small (SVL<35mm) and slender with clearly upturned snout. ............................. Leptodactylus latinasus anceps
12b Medium-sized (SVL 60-65mm) and robust. Snout sharpened, but not upturned. ......... Leptodactylus bufonius

13a Dorsal skin pustular and irregularly warty. Ventral greyish with heavily speckled with fine white circular spots. Snout rounded in lateral view. ................................................................................ Leptodactylus podicipinus
13b Dorsal skin smooth. Ventral uniformly pale. Snout slightly truncate in lateral view. ....... Leptodactylus diptyx