Weird and Wonderful: The fish-eating siphonophore Erenna

This intricate gelatinous animal, armed with powerful stinging tentacles, is the fish-eating siphonophore, Erenna sirena. The individuals that comprise the front half of this colonial animal are specialized for swimming and those in the back, for reproduction and feeding. It attracts prey by wiggling an array of bioluminescent red lures. These unusual creatures are too fragile to survive traditional collection methods--they completely fall to pieces in nets. Scientists are just beginning to learn more using remotely operated vehicles that allow us to carefully observe them in their natural habitat.

Images at 0:10 (filmed in blue light with a yellow filter to highlight the fluorescence); 00:24; 0:29 courtesy of Steve Haddock.

Publication citation: Pugh, P.R. and S.H.D. Haddock (2016). A description of two new species of the genus Erenna (Siphonophora, Physonectae, Erennidae), with notes on recently collected specimens of other Erenna species. Zootaxa. 4189: 401-446. doi:10.11646/zootaxa.4189.3.1.

Video editor: Ted Blanco
Writer: Kyra Schlining
Production team: Nancy Barr, Nancy Jacobsen Stout, Heidi Cullen