In 2006 two eager shell collectors hauled in some small but strangely shaped mollusks in deep water off Key West, Florida. Like the good animal nerds they were, they brought their findings to a shell collectors convention in Mobile, Alabama where the Director of the Bailey-Matthews Shell Museum on Sanibel Island, Jose H. Leal, took up the challenge of identifying the critters.
Two years later, Leal finally published his findings in the May 7th edition of Zootaxa, announcing that the heart-shaped bivalves were an entirely new genus. As explained to Florida's News-Press by Leal, "This particular clam is a rare, totally unheard of clam that eats small shrimp and at the same time is permanently attached to rocky bottoms... Usually they are out and about because they need to move a little and hunt for their little prey." The description in Zootaxa is a little less definitive "...discovery of the new genus reveals an unusual instance of predation by sessile, permanently attached mollusks." It would surprise me if this behavior really was totally unique... but I'm no molluscologist. Paging Dr. Z...
Dilemma Frumarkernorum gets its 1:27 minutes of fame (CAUTION: loud ads)
Full Zootaxa paper available here.
A photo of the critter is included below the fold in anticipation of the video link breaking at some point and readers in the distant future of 2009 writing me in protest.







Comments
Time for a "vacation" to Fla.
"Honest it was all work related...."
Posted by: Eric | June 3, 2008 1:33 PM
Cool find Bleimy! Yes it is rare for a carnivore to lose mobility. Other clams use their muscular foot to move around reposition itself. Clams typically are passive feeders, filtering organic material out of the water column. This can include plankton and bacteria, but rarely if ever specialize on a mobile animal, such as a shrimp.
Posted by: kevin z | June 3, 2008 3:37 PM
A few bivalves (Poromyidae, Verticordiidae, Cuspidariidae) are carnivores. They're mostly infaunal, living in sediment, but I dunno if they're attached to anything. They're probably not very mobile as adults, although they might hurtle around like go karts when no one's looking. Who knows?
Posted by: Snail | June 4, 2008 6:16 AM