C. fimbriatus is one of the most common beetles on the sandy beach. Their body size ranges from 2.5mm to 4.0mm. Wide color variations are seen commonly within these beetles. They can be distinguished from clown beetles by their golden coloration (when present) and straight elytral lines. C. fimbriatus are found in large numbers across all beaches throughout the year, but can be seen in largest concentrations around spring and summer. They are herbivorous and potentially consume fly larvae and dead arthropods. The high numbers of these beetles mean they can be a more significant factor in kelp removal on beaches than most beetles.