Crocodylus is derived from the Greek krokodeilos which means literally "pebble worm" and rhombifer apparently refers to the shape of flank scales.
It is a medium-sized crocodile, reaching 3.5 m in length (although 5 m individuals have been reported) - slightly smaller than C. acutus. Head is short and broad, and a bony ridge is present behind eyes. Scales forming the dorsal shield (across the back) extend onto the back of the neck, and scales on the legs are unusually large, and heavily keeled on the rear legs.
Juveniles possess eyes with a light iris, which is reported to become darker with age. A characteristic yellow and black patterning has led to the name 'Pearly' crocodile. Its diet is mainly fish and chelonia, with the occasional small mammal.