Designed by Paul Smith 2006. This website is copyrighted by law.
Material contained herewith may not be used without the prior written permission of FAUNA Paraguay.
Photographs on this web-site were taken by Paul Smith, Hemme Batjes, Regis Nossent,
Alberto Esquivel, Arne Lesterhuis, José Luis Cartes, Rebecca Zarza and Hugo del Castillo and are used with their permission.
HYLIDAE - TREE-FROGS
Twenty-eight species in three subfamilies occur in Paraguay. Tree-frogs typically have well-developed digital pads and are adapted to a basically arboreal existence (except Pseudinae). They possess eight free procoelous, holochordal presacral vertebrae. The urostyle is free with two condyles and there are no ribs. The pectoral girdle is arciferal and the sternum and omosternum are cartilaginous. Palatines are usually present and the clavicle does not overlie the scapula. Teeth are present on the maxilla and premaxilla. The astralagus and calcaneum are fused only at the ends. Cartilaginous penultimate intercalary phalanges in each digit. Sartorius muscle separate and distinct. Aquatic larvae. Sperm usually with single filament, but double filament in some species. 2n=22 to 34 (most commonly 24).
The characteristics of the three subfamilies are detailled below:
Subfamily Hylinae - Tree-frogs - Rafinesque 1815
Generalised tree-frogs. Mandibularis not differentiated in most cases, but where differentiated lacks an apical element. Pupil horizontal. Sperm with single tail filament, except for in Scinax. 2n=24 or 30. Worldwide distribution. Subfamily as it stands probably does not represent a monophyletic unit. The majority of the members of the subfamily Hylinae were formerly placed in the genus Hyla. This genus is now applied only to Old World species, the New World "Hyla" being placed in two separate genera Hypsiboas (for larger species) and Dendropsophus (for smaller species). The generic change necessitated nomenclatural adjustments in some cases.
Subfamily Phyllomedusinae - Leaf Frogs - Günther 1815
Mandibularis not differentiated and lacking distinct intermandibularis. Pupil vertically elliptical. Thumb opposable. Arboreal egg deposition and aquatic larvae. Sperm with two unequal tail filaments. Dermis of skull sometimes co-ossified. 2n=26. Confined to New World.
Subfamily Pseudinae - Paradox Frogs - Fitzinger 1843
Bony intercalcary phalanges. Eggs and larvae aquatic, larvae extremely large - larger than adult form - creating the "paradox" of the common name. Adults semi-aquatic with fully-webbed toes. 2n=24. Confined to New World.
REFERENCES
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.
