Cricetidae—Part 1

Abstract

Cricetids are small rodents. Because it is such a diverse family of rodents, many features of the skull are quite variable. The braincase is relatively inflated and the rostrum narrow (Fig. 20.1). The zygomasseteric structure is either hystricomorphous (infraorbital foramen enlarged for passage of the masseter medialis) or myomorphous (passage of masseter medialis through the infraorbital foramen and extension of the masseter lateralis onto the rostrum forming a tilted zygomatic plate). The incisive foramina vary in size from large to small depending on the subfamily. The zygoma is usually slender. The temporalis scar is limited to the lateral margins of the parietal bones except in eumyines where a distinct sagittal crest may be formed. The auditory bullae vary in size from small to greatly inflated.