Fig. 6 in Revisionary Notes on Neotropical Porcupines (Rodentia: Erethizontidae). 2. A Review of the Coendou vestitus Group with Descriptions of Two New Species from Amazonia

Fig. 6. Ventrolateral cranial views of Coendou vestitus (A, AMNH 71360) and C. pruinosus (B, MCZ 18738) showing species differences in alisphenoid morphology. In Coendou vestitus, the alisphenoid is incompletely ossified, resulting in an open sphenopterygoid canal and a buccinator­masticatory foramen (bmf) that is confluent with the foramen ovale (fo). By contrast, the alisphenoid is fully ossified in C. pruinosus, whose sphenopterygoid canal (arrow) is laterally enclosed and whose buccinator­masticatory and oval foramina are separate.