Search results
Results from the WOW.Com Content Network
In tetrapods with a quadratojugal bone, it often forms a portion of the jaw joint. Developmentally, the quadratojugal bone is a dermal bone in the temporal series, forming the original braincase. The squamosal and quadratojugal bones together form the cheek region [4] and may provide muscular attachments for facial muscles. [5]
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 ...
The posterior end of the lower jaw bones contains a quadrate bone, allowing jaw extension. The anterior tips of the lower jaw bones are joined by a flexible ligament allowing them to bow outwards, increasing the mouth gape. [76] [77] The Pacific tree frog and the Baja California chorus frog are some of the only frog species that make a "ribbit ...
The tuatara and some extinct rhynchocephalians have a more rigid skull with a complete lower temporal bar closing the lower temporal fenestra formed by the fusion of the jugal and quadrate/quadratojugal bones, similar to the condition found in primitive diapsids. However early rhynchocephalians and lepidosauromorphs had an open lower temporal ...
The squamosal is a skull bone found in most reptiles, amphibians, and birds. In fishes, it is also called the pterotic bone. [1] In most tetrapods, the squamosal and quadratojugal bones form the cheek series of the skull. [2] The bone forms an ancestral component of the dermal roof and is typically thin compared to other skull bones. [3]
In the English language, many animals have different names depending on whether they are male, female, young, domesticated, or in groups. The best-known source of many English words used for collective groupings of animals is The Book of Saint Albans, an essay on hunting published in 1486 and attributed to Juliana Berners. [1]
A correspondingly large intervomerine fontanelle is found on the palate. The quadratojugal is expanded, and in Acanthostomatops and Zatrachys, bears discrete spiky projections. The quadratojugal also obscures the quadrate in dorsal profile. Dasyceps and Zatrachys are only confidently known from cranial material.
The complete lower temporal bar (caused by the fusion of the jugal and quadtrate/quadratojugal bones of the skull) of the tuatara, often historically asserted to be a primitive feature retained from earlier reptiles, is actually a derived feature among sphenodontians, with primitive lepidosauromorphs and many rhynchocephalians including the ...