Structural features of the head skeleton of the Asian (white-tailed) porcupine (Hystricidae levicura)

The purpose of research is to study the structural features of the head skeleton of the Asian (white-tailed) porcupine. The object of the study is the skeleton of the head of an Asian (white-tailed) porcupine at the age of 12 years. To make the porcupine skeleton, a biological method of processing the material was used. The study of the bones was accompanied by measuring their length and width using an electronic caliper with an accuracy of 0.1 mm, describing and photographing. The head skeleton of the Asian (white-tailed) porcupine is divided into cerebral and facial sections, the size of which is related to the size of the brain and the development of the masticatory apparatus. The brain region is represented by unpaired (occipital, sphenoid, interparietal, ethmoid) and paired (temporal, frontal, parietal, alar) bones. The facial region is represented by the maxillary, incisive, palatine, zygomatic, lacrimal and nasal bones. The rostral edge of the orbit serves as the boundary between the facial and brain regions. The facial section reaches the greatest development, occupying 59.8 % of the length of the brain. The configuration of the skull and the presence of a large number of processes make it possible to attach well-developed masticatory muscles to it. The caudal part of the skull is represented by the occipital bone, and the cranial part by the ethmoid bones. The body of the occipital bone is connected to the sphenoid bone, which participates in the formation of the foramen lacerum. The body of the sphenoid bone is trapezoidal in shape, from which the orbital and temporal wings branch. There are six foramina on the orbital wing: optic, orbital fissure, round, caudal alar, oval and carotid. The temporal wing is involved in the formation of the foramen lacerum with the oval, spinous and carotid notches. On the facial surface of the maxillary bone there is a facial ridge; between its facial and nasal surfaces there is an extensive maxillary sinus. The mandibular bone is paired, represented by two bones connected to each other by a ligament. The massive, triangular-shaped lower jaw has two processes: the condylar and the coronoid. The condylar process is convex, oval-elongated. The coronoid process is low with a bifurcated apex. The pterygoid and chewing fossae are deep and triangular in shape.