Parietal bone

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Side view of the skull:
1. Frontal bone (Os frontale)
2. Parietal bone (Os parietale) (blue)
3. Nasal bone (Os nasale)
4. Ethmoid bone (Os ethmoidale)
5. Lacrimal bone (Os lacrimale)
6. Sphenoid bone (Os sphenoidale)
7 . occiput (occipital)
8. temporal bone (temporal bone)
9. cheekbone (zygomatic bone)
10. upper jaw (maxilla)
11 lower jaw (mandible)

The paired parietal bone ( Latin os parietale ') is a part of the brain skull . It forms the roof of the skull and the side wall of the bony brain capsule . In ruminants , due to the very large frontal bone , only the side part of the skullcap is formed by the parietal bone.

Representation of the parietal bone.

In humans, the parietal bone is bounded by several cranial sutures : Sutura sagittalis (between the left and right parietal bones), Sutura coronalis (in front, towards the frontal bone) and Sutura lambdoidea (behind, towards the occipital bone ). In the newborn, fontanelles are formed between the parietal bone on the one hand and the frontal bone ( Fonticulus major ), the wedge bone ( Fonticulus sphenoidalis ), the occiput ( Fonticulus minor ) and the temporal and occipital bone ( Fonticulus mastoideus ) .

In all mammals , the parietal bone is connected to the temporal and sphenoid bones by a bone suture.

The temporalis muscle, one of the masticatory muscles, originates on the side of the parietal bone . The upper limit of its origin forms a clear line, the linea temporalis . With the exception of humans and ruminants, the temporal lineae on both sides combine to form a strong median bone ridge ( crista sagittalis externa ) on the upper roof of the skull.

Occipital there are sometimes small holes in the bone as passage points for vessels, so-called foramina parietalia .

Skull of a sheep
os parietale marked in color


In the radiation fins (Actinopterygii), a class of bony fish , the bone that is homologous to the parietal bone of the meat fins (Sarcopterygii) and terrestrial vertebrates (Tetrapoda) is referred to as the frontal, which can be confused with the frontal bone (os frontale) of the meat fins and land vertebrates can lead. The parietal of the ray fins is homologous to the post parietal of the meat fins and terrestrial vertebrates.

Web links

Commons : Parietal Bone  - Collection of images, videos, and audio files

Individual evidence

  1. Federative Committee on Anatomical Terminology (FCAT) (1998). Terminologia Anatomica . Stuttgart: Thieme
  2. ^ A b Franz-Viktor Salomon: Bony skeleton . In: Franz-Viktor Salomon et al. (Hrsg.): Anatomie für die Tiermedizin . 3. Edition. Enke, Stuttgart 2015, ISBN 978-3-8304-1288-5 , pp. 94 .
  3. ^ EO Wiley & G. David Johnson: A teleost classification based on monophyletic groups. Page 129 in Joseph S. Nelson , Hans-Peter Schultze & Mark VH Wilson: Origin and Phylogenetic Interrelationships of Teleosts. Publishing house Dr. Friedrich Pfeil, Munich 2010, ISBN 978-3-89937-107-9 .