Dondice parguerensis, Brandon & Cutress, 1985 (revisited)
Dondice parguerensis is one of the most fascinating aeolid nudibranchs found in the Caribbean. This species lives its entire life cycle in association with the scyphozoan medusa Cassiopea frondosa, otherwise known as the upside down jellyfish. As the name suggests it was originally described from La Parguera, Puerto Rico. Anne's photo here was taken at Lake Worth Lagoon, Riviera Beach, Florida, in only 12 feet of water. See Caribbean Sea Slugs , page 252, for more photos.
This nudibranch/jelly association is not symbiotic as the Branch is deriving all the benefit, food, protection and substrate; the poor jellyfish, gets nothing in return. The eggs are even laid directly on the jelly and the larvae are thought to settle directly upon the medusa.
This species differs from the other Caribbean species, Dondice occidentalis , in three noticeable characteristics. D. parguerensis is larger, reaching 48 mm ( D. occidentalis is rarely over 30 mm). It has nine groups of cerata (D. occidentalis has six) and it lacks the red medial stripe that runs along the head and body to the tail. Seen here, the color of D. parguerensis closely matches that of the of the jellyfish.
Although quite cryptically colored , Dondice parguerensis is relatively easy to find and photograph because of exclusive occurrence of its specific food preference. The next time you see Cassiopea pulsating rhythmically on the bottom, pick it up and take a close look at the tentacles of the jellyfish.
Anne DuPont on location in the Bahamas
Anne DuPont is a scientific diver and underwater photographer specializing in opisthobranchs and polyclad flatworms. She is a Museum Associate in Malacology at the Natural History Museum of Los Angeles County and is a volunteer scientific diver and underwater photographer for the "Flatworm Wrangler's Team" at the University of New Hampshire. She also works with the Natural History Museum of Florida. Her photos have been published in numerous books, magazines, and educational DVDs.
Anne is retired from IBM. She and her husband live in Delray Beach, Florida. They spend 4 months a year on their trawler in the Bahamas. Her favorite pastime at home is "muck" diving in Lake Worth Lagoon.
She is one of the co-authors of " Caribbean Sea Slugs , A field guide to the opisthobranch mollusks from the tropical northwestern Atlantic."
Send Anne email at email@example.com