The Muscles of Mastication in the Caspian Seal (Phoca caspica)

  title={The Muscles of Mastication in the Caspian Seal (Phoca caspica)},
  author={Hideki Endo and Shinji Sakata and Takaomi Arai and Nobuyuki Miyazaki},
The muscles of mastication and their related skull characters in the Caspian seal (Phoca caspica) were anatomically examined and compared with those of the Baikal (Phoca sibirica) and ringed (Phoca hispida) seals. A well‐developed masseter muscle was observed in the Caspian seal, whereas the temporal muscle consisted of thin bundles. The skull of the Caspian seal possessed the same thin frontal bone and the dorso‐ventrally developed zygomatic arch found in the Baikal seal that are required to… 
Muscles of Mastication and the Temporo-Mandibular Joint of the Saimaa (Pusa hispida saimensis) and Baltic (Pusa hispida botnica) Ringed Seals
The authors' data on masticatory-muscle masses indicated that similarly to terrestrial mammal species, the growth patterns of mastication muscles of the Saimaa ringed seal differed from each other according to the body size.
Comparative study of the digastric and the stylohyoid muscles between wild boars (Sus scrofa scrofa) and domestic swine (Sus scrofa domesticus): revisiting the gross anatomy
The digastric muscle presented only one muscle belly as anatomical component of a tendinous origin in the jugular process of the occipital bone, and muscle insertion in the midventral edge of the caudal two thirds of the body of the mandible which, by the way, can deliver greater muscle power at lesser energy expense.
Comparison of the musculoskeletal forelimb anatomy of the Saimaa ( Pusa hispida saimensis ) and Baltic ringed seals ( Pusa hispida botnica )
The unique evolutionary history of the Saimaa ringed seal offers an excellent opportunity for comparative anatomical studies with other ringed Seal subspecies adapted to different habitats, but such studies are also challenging due to the endangered status of the endangered seal.
Variation and Integration of the Simple Mandibular Postcanine Dentition in Two Species of Phocid Seal
PC size in ringed and harp seals was slightly more variable than cheek teeth in complex dentitions of fissipeds, and the 2 seals were similar to fissIPeds in strong bilateral symmetry in mandibular and PC size, patterned variation along the toothrow, and correlated size between adjacent PCs.


Functional relationship between muscles of mastication and the skull with enlarged orbit in the Baikal seal (Phoca sibirica).
It is suggested that the Baikal seal has especially developed the Mm. temporalis and masseter using an enlarged area of zygomatic arch among Pusa species and the robust temporal bone is equipped to have the M. digastricus developed as a main retractor of mandibular body in the ringed seal.
It is suggested that the M. orbicularis oculi muscles move the eye and palpebral area and constitute a morphological and synergistic facial muscle complex system.
CT examination of the head of the Baikal seal (Phoca sibirica)
It is suggested that adaptation for the Lake Baikal environment primarily resulted in orbital enlargement, and that the altered orbital design may subsequently have influenced the form and function of the masticatory and respiratory system.
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Craniometric characteristics of the Baikal seal
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Morphological characteristics of the ringed seal ( Pusa hispida ; Pinnipedia , Mammalia ) in the Okhotsk Sea
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Anatomical notes on Pinnipedia and Cetacea
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