Lindeberg, 1970
Body
Medium sized larvae up to 7 mm long. The posterior parapods bear only simpel claws (Wiederholm, 1983).
Head
S3 is simpel.
Antenna
The antenna stands on a tall smooth pedestal and consists of 5 segments. The basal segment is much longer than the flagellum Tatars antenna. Segment 2 is cylindrical and longer than the remaining segments. The pedestals of the small Lauterborn organs reach far beyond the antennal apex.
Mentum
The mentum consists of 3 median mental teeth, and set backwards 2 sets of 4 pairs of lateral teeth. The ventromental plates are close together medially and wider than the mentum.
Labrum
SI is a comb and labral lamellae a single plate with numerous apical teeth. The pecten epipharyngis consists of 3 smooth plates with distal teeth. The premandible has 5 teeth.
Mandible
The mandible has 3 dorsal teeth, one apical tooth and 3 inner teeth. An additional toothed lobe is present on the dorsal side of the mandible Cor oliveri mandible. The pecten mandibularis is present and seta interna with branches.
Differential characteristics
The mentum is distinctive for the genus in having a central and dorsal or lateral part with only 1-2 or 4 pairs of teeth Cor ambigua mentum small.
C. oliveri can be separated from C. ambigua by the teeth and lobes on the mandible and the mentum flatter and 4 pairs of lateral teeth.