FIGURE 1.

(A) Higher magnification of the segmented cranial air-filled spaces in the living C. rhombifer. The meatal chambers are fully aerated and open to the air anteriorly in a thin slit (broken lines). The ears are internally coupled caudally. (B) and (C) Frontal section at the posterior region of the tympanic cavity (TC) with aerated meatal recesses. Columellae and tympanic membranes are visible. The peritympanic air spaces continue into the pharynx (bold arrow) (C) Ears are also internally coupled rostrally.