from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Of or relating to the thin, platelike part of the human temporal bone or to a corresponding part in other vertebrates.
- n. A squamosal bone.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Of or pertaining to the platelike part of the temporal bone
from the GNU version of the Collaborative International Dictionary of English
- adj. Scalelike; squamous.
- adj. Of or pertaining to the squamosal bone.
from The Century Dictionary and Cyclopedia
- Scale-like or squamous: noting only the squamosal, See II.
- n. In zoology and anatomy, the squamous division of the temporal bone; the thin, expansive, scale-like element of the compound temporal bone; a membrane-bone, morphologically distinct from other parts of the temporal, filling a gap in the cranial walls, articulating in man and mammals with the lower jaw, in birds and reptiles with the suspensorium (quadrate bone) of the lower jaw, effecting squamous suture with various cranial bones, and forming by its zygomatic process in mammals a part of the zygoma, or jugal bar.
The squamosal-parietal contact isn't exactly right, which I tried to fix in the final version.
Anyway, within this group, an affinity between Aldabrachampsus and ‘Crocodylus’ robustus is particularly plausible given that both taxa share a vaulted palate and large squamosal crests.
However, its most obvious feature would almost certainly have been the convex crests that grew from the dorsolateral edges of the squamosal bones at the back of its skull.
A few cranial elements are preserved, including parts of a parietal, squamosal, maxilla, and two dentaries.
Only the raised bar along the squamosal/parietal suture, present in T. latus; and the midline epiparietal, absent in T. latus, may discriminate the two species.
At the same time, notwithstanding the great length of the skull, the sagittal suture is remarkably short (4 1/2 inches), and the squamosal suture is very straight.
Under whatever aspect we view this cranium, whether we regard its vertical depression, the enormous thickness of its supraciliary ridges, its sloped occiput, or its long and straight squamosal suture, we meet with ape-like characters, stamping it as the most pithecoid of human crania yet discovered.
In this animal, not only was the ancient reptilian joint between a reduced quadrate and articular still present, but also the new mammalian joint between the squamosal and dentary bones had come into functional being.
In mammals, by contrast, the lower jaw is made up of a single bone, the dentary, which articulates with the squamosal bone in the skull to form the jaw joint.
The therapsid-mammal transition was completed with the appearence of the morganucodonts in the late Triassic: The axes of the two jaw hinges, dentary-squamosal and articular-quadrate, coincide along a lateral-medial line, and therefore the double jaw articulation of the most advanced cynodonts is still present … The secondary dentary-squamosal jaw hinge had enlarged in the morganucodonts and took a greater proportion if not all of the stresses at the jaw articulation.
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