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Salamanders, caecilians and some frogs have one or two rows of teeth in both jaws, but some frogs (Rana spp.) lack teeth in the lower jaw, and toads (Bufo spp.) have no teeth. In many amphibians there are also vomerine teeth attached to a facial bone in the roof of the mouth. [144] Edible frog (Pelophylax esculentus) exhibiting cannibalism
Most amphibians have one or two rows of teeth in both jaws but some frogs lack teeth in the lower jaw. In many amphibians, there are also vomerine teeth attached to the bone in the roof of the mouth. [15] The mouths of reptiles are largely similar to those of mammals. The crocodilians are the only reptiles to have teeth anchored in sockets in ...
Amphibians today generally remain semi-aquatic, living the first stage of their lives as fish-like tadpoles. Several groups of tetrapods, such as the reptillian snakes and mammalian cetaceans, have lost some or all of their limbs, and many tetrapods have returned to partially aquatic or (in the case of cetaceans and sirenians) fully aquatic lives.
The lower jaw is specialized in caecilians. Gymnophionans, including extinct species, have only two components of the jaw: the pseudodentary (at the front, bearing teeth) and pseudoangular (at the back, bearing the jaw joint and muscle attachments). These two components are what remains following fusion between a larger set of bones.
Gastrotheca guentheri is the only known frog with true teeth in its lower jaw. [ 2 ] [ 6 ] Its teeth have re-evolved after being absent for over 200 million years, challenging Dollo's law . [ 6 ] Re-evolution of teeth in the lower jaw may have been made easier because the frogs have teeth in their upper jaw so there was already a biochemical ...
The muscles of the jaw give them the ability to grab and hold on to prey as well as create a negative pressure to suck in the prey and displace the jaw. Muscles of note in the amphiuma include: the levator mandibulae anterior and levator mandibulae externus, which elevate the lower jaw of the amphiuma while the depressor mandibulae depresses ...
Many fish have modified posterior gill arches into pharyngeal jaws, often equipped with specialized pharyngeal teeth for handling particular prey items (long, sharp teeth in carnivorous moray eels compared to broad, crushing teeth in durophagous black carp). In amphibians and reptiles, the hyoid arch is modified for similar reasons.
The quadrate bone is a skull bone in most tetrapods, including amphibians, sauropsids (reptiles, birds), and early synapsids. In most tetrapods, the quadrate bone connects to the quadratojugal and squamosal bones in the skull, and forms upper part of the jaw joint. The lower jaw articulates at the articular bone, located at the rear end of the ...