Arthroleptidae

Arthroleptidae ( /ˌɑrθrɵˈlɛptɨdiː/) is a family of frogs found in Sub-Saharan Africa. They are also known as squeakers because of their high-pitched call. They are small, less than 4 centimetres (1.6 in) in length, terrestrial frogs found mostly in leaf litter on the forest floor. They completely bypass any aquatic stage, and therefore do not have tadpoles. They lay their eggs on the ground, in crevices or in leaf litter, and the offspring undergo direct development. Some species hatch already completely metamorphosed into the adult form, while others still have tails when they hatch^[1].

Contents 1 Overview 2 Taxonomy 3 References 4 Further information

Overview

This family contains a unique frog, the Hairy Frog (Trichobatrachus robustus). Breeding male Hairy Frogs develop highly vascularised, hair-like projections on their thighs and flanks. They will sit on their eggs for long periods of time, and it is thought that the hairs assist in respiration through the skin, while they cannot use their lungs in the water. The hairy frog is also notable in possessing retractable "claws" (though unlike true claws, they are made of bone, not keratin), which is may project through the skin, apparently by intentionally breaking the bones of the toe ^[1]. In addition, the researchers found a small bony nodule nestled in the tissue just beyond the frog's fingertip. When sheathed, each claw is anchored to the nodule with tough strands of collagen, but when the frog is grabbed or attacked, the frog breaks the nodule connection and forces its sharpened bones through the skin.

Amphibian researcher and biologist David Wake of the University of California, Berkeley, says that this type of weaponry appears to be unique in the animal kingdom. But David Cannatella, a herpetologist at the University of Texas, Austin, questions whether the bony protrusions are meant for fighting. They could allow a frog's feet "to get a better grip on whatever rocky habitat they might be in," he says.^[2]

Taxonomy

Arthroleptidae is separated into two sub-families: Arthroleptinae and Leptopelinae. Some consider these to be separate families ^[2].

The two sub-families consist of the following genera:

Subfamilia	Spe- cies	Common name	Scientific name
Arthroleptinae Mivart, 1869
	37	Screeching Frogs	Arthroleptis Smith, 1849
	11	Night Frogs	Astylosternus Werner, 1898
	15	Long-Fingered Frogs	Cardioglossa Boulenger, 1900
	15	Egg Frogs	Leptodactylodon Andersson, 1903
	1	Southern Night Frog	Nyctibates Boulenger, 1904
	1	Gaboon Forest Frog	Scotobleps Boulenger, 1900
	1	Hairy Frog	Trichobatrachus Boulenger, 1900
Leptopelinae Laurent, 1972	51	Forest Treefrogs	Leptopelis Günther, 1859

References

^ *" 'Horror frog' breaks own bones to produce claws." NewScientist.com, 2008

^ *Amphibian Species of the World - Arthroleptidae Mivart, 1869

Further information

• ADW: Arthroleptidae: Information
• Cogger, H.G.; R.G. Zweifel, and D. Kirschner (2004). Encyclopedia of Reptiles & Amphibians Second Edition. Fog City Press. ISBN 1-877019-69-0. 

Extant anuran families by suborder Kingdom Animalia Phylum Chordata Subphylum Craniata Superclass Tetrapoda Class Amphibia Archaeobatrachia Ascaphidae Bombinatoridae Discoglossidae Leiopelmatidae Mesobatrachia Megophryidae Pelobatidae Pelodytidae Pipidae Scaphiopodidae Rhinophrynidae Neobatrachia Amphignathodontidae Aromobatidae Arthroleptidae Brachycephalidae Bufonidae Centrolenidae Craugastoridae Dendrobatidae Heleophrynidae Hemiphractidae Hemisotidae Hylidae Hyperoliidae Leptodactylidae Mantellidae Microhylidae Myobatrachidae Petropedetidae Pyxicephalidae Ranidae Rhacophoridae Rhinodermatidae Sooglossidae