Deep-Sea, Swimming Worms with Luminescent "Bombs"

• Published in: Science (American Association for the Advancement of Science) Vol. 325; no. 5943; p. 964
• Main Authors: Osborn, Karen J., Haddock, Steven H. D., Pleijel, Fredrik, Madin, Laurence P., Rouse, Greg W.
• Format: Journal Article
• Language: English
• Published: Washington, DC American Association for the Advancement of Science 21-08-2009; The American Association for the Advancement of Science
• Subjects: Acrocirridae; Animal populations; Animals; Annelida; Annelida and closely related phyla: sipuncula. Echiura. Nemertinea; Aquatic life; Biological and medical sciences; Bioluminescence; Brevia; Ecology; Ecosystem; Ekologi; Evolutionary biology; Fundamental and applied biological sciences. Psychology; Genomics; Invertebrates; Luminescence; Marine; Microbiology; Mikrobiologi; Molecular Sequence Data; Ocean floor; Oceanography; Polychaeta - anatomy & histology; Polychaeta - classification; Polychaeta - genetics; Polychaeta - physiology; Seawater; Swimming; Worms; West Pacific; Pacific Ocean; Northeast Pacific; Bioluminescence; Taxonomy; Luminescence; Diagnosis (taxonomy); Defense mechanism; Deep water; Invertebrata; Anatomy; Autotomy; Annelida
• ISSN: 0036-8075; 1095-9203
• DOI: 10.1126/science.1172488

By using remotely operated vehicles, we found seven previously unknown species of swimming annelid worms below 1800 meters. Specimens were large and bore a variety of elaborate head appendages. In addition, five species have pairs of ellipsoidal organs homologous to branchiae that produce brilliant green bioluminescence when autotomized. Five genes were used to determine the evolutionary relationships of these worms within Cirratuliformia. These species form a clade within Acrocirridae and were not closely related to either of the two known pelagic cirratuliforms. Thus, this clade represents a third invasion of the pelagic realm from Cirratuliformia. This finding emphasizes the wealth of discoveries to be made in pelagic and deep demersal habitats.