This list of Anuran families shows all extant

families Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideal ...

of Anura. Anura is an order of animals in the class

Amphibia Amphibians are four-limbed and ectothermic vertebrates of the class Amphibia. All living amphibians belong to the group Lissamphibia. They inhabit a wide variety of habitats, with most species living within terrestrial, fossorial, arbor ...

that includes

frog A frog is any member of a diverse and largely carnivorous group of short-bodied, tailless amphibians composing the order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-frog" ''Triadobatrachus'' is ...

s and

toad Toad is a common name for certain frogs, especially of the family Bufonidae, that are characterized by dry, leathery skin, short legs, and large bumps covering the parotoid glands. A distinction between frogs and toads is not made in scient ...

s. More than 5,000 species are described in the order. The living anurans are typically divided into three suborders:

Archaeobatrachia Archaeobatrachia (New Latin ''archaeo-'' ("old") + ''batrachia'' ("frog")) is a suborder of the order Anura containing various primitive frogs and toads. As the name suggests, these are the most primitive frogs. Many of the species (28 in total) ...

, Mesobatrachia, and

Neobatrachia The Neobatrachia (New Latin ''neo-'' ("new") + ''batrachia'' ("frogs")) are a suborder of the Anura, the order of frogs and toads. This suborder is the most advanced and apomorphic of the three anuran suborders alive today, hence its name, whi ...

. This classification is based on such morphological features as the number of vertebrae, the structure of the pectoral girdle, and the morphology of tadpoles.

Taxonomy

The archaeobatrachians are the most primitive of frogs. These frogs have morphological characteristics which are found mostly in extinct frogs, and are absent in most of the modern frog species. Most of these characteristics are not common between all the families of Archaeobatrachia, or are not absent from all the modern species of frogs. However, all archaeobatrachians have free vertebrae, whereas all other species of frogs have their ribs fused to their vertebrae. The Neobatrachia comprise the most modern species of frogs. Most of these frogs have morphological features which are more complex than those of the mesobatrachians and archaeobatrachians. The neobatrachians all have a palatine bone, which braces the upper jaw to the

neurocranium In human anatomy, the neurocranium, also known as the braincase, brainpan, or brain-pan is the upper and back part of the skull, which forms a protective case around the brain. In the human skull, the neurocranium includes the calvaria or skul ...

. This is absent in all Archaeobatrachia and some Mesobatrachia. The third distal

carpus In human anatomy, the wrist is variously defined as (1) the carpus or carpal bones, the complex of eight bones forming the proximal skeletal segment of the hand; "The wrist contains eight bones, roughly aligned in two rows, known as the carpal ...

is fused with the remaining carpal bones. The

adductor longus In the human body, the adductor longus is a skeletal muscle located in the thigh. One of the adductor muscles of the hip, its main function is to adduct the thigh and it is innervated by the obturator nerve. It forms the medial wall of the fem ...

muscle is present in the neobatrachians, but absent in the archaeobatrachians and some mesobatrachians. It is believed to have differentiated from

pectineus muscle The pectineus muscle (, from the Latin word ''pecten'', meaning comb) is a flat, quadrangular muscle, situated at the anterior (front) part of the upper and medial (inner) aspect of the thigh. The pectineus muscle is the most anterior adductor o ...

, and this differentiation has not occurred in the primitive frogs. The Mesobatrachia are considered the evolutionary link between the Archaeobatrachia and the Neobatrachia. The families within the mesobatrachian suborder generally contain morphological features typical of both the other suborders. For example, the palatine bone is absent in all archaeobatrachians, and present in all neobatrachians. However, within the mesobatrachians families, it can be dependent on the species as to whether the palatine bone is present. Due to the many morphological features which separate the frogs, many different systems are used for the classification of the anuran suborders. These different classification systems usually split the Mesobatrachia suborder.

Families

References

* * * *{{cite web , last = Cannatella , first = David , author2=Ford, Linda , author3=Bockstanz, Lori , year =1995 , url = http://tolweb.org/Neobatrachia/16987 , title = Neobatrachia , publisher = Tree of Life Web Project , access-date = 2006-05-19

Anuran A frog is any member of a diverse and largely Carnivore, carnivorous group of short-bodied, tailless amphibians composing the order (biology), order Anura (ανοὐρά, literally ''without tail'' in Ancient Greek). The oldest fossil "proto-f ...