Cadlina rumia is a species of sea slug or dorid nudibranch, a marine gastropod mollusk in the family Cadlinidae.

[2] Distribution in Western Atlantic includes: Florida, Belize, Panama, Venezuela, Bahamas, Dominican Republic, Jamaica, Puerto Rico, Curaçao, St. Maarten/St.

[2] Distribution in Eastern Atlantic includes: ...[further explanation needed] Its body is oval and flat, covered with numerous small tubercles.

[2] Minimum and maximum recorded depth is 0 m.[3] Cadlina rumia was found under rocks and on various sponges.

[2] Prey of Cadlina rumia include sponges Dysidea etheria, Haliclona sp., Callyspongia sp.