The living specimen was 28 mm in length and 7 mm wide. The general body color of the living animal (Fig. 1C) is whitish with a “v”-shaped maroon patch present on the head. Maroon spots are present along the parapodial margins. The entire dorsal and lateral surfaces of the body are ornamented with scattered, irregular yellow spots and a few whitish patches. The ventral surface of the single animal is pale pink with a series of large yellowish and maroon spots on the foot. Living animals are elongate and wide. The anterior end of the cephalic shield is indented but blunt and quadrangular. The cephalic shield is roughly rectangular and terminates posteriorly with an elongate, rounded papilla. The posterior shield is slightly rounded anteriorly and terminates in an elongate conical posterior protrusion that is well-elevated from the base of the shield. The two lateral posterior lobes of the posterior shield are elongate and simply rounded. The left posterior lobe is longer than the right one. The parapodia are very short, leaving most of the cephalic and posterior shields visible. The gill is simply plicate consisting of 13 primary folds and is situated on the right posterior side of the animal.
Known only from the Philippines
The name “coronata” comes from the Latin corona, meaning crown. This refers to the ring of rounded tubercles at the apex of the penis, which resemble a crown.