1. Introduction Octocorals are Anthozoans in the subclass Alcyonaria. They are commonly referred to as gorgonians, and they are most easily identified by eight pinnate tentacles surrounding the polyp's oral disk. The order Alcyonacea is species rich, with more than 2800 species documented worldwide, compared to some 1500 scleractinians. They range from the equator to the poles, from the subtidal to the abyss. Octocorals are filter feeders, often orienting in a perpendicular fashion to prevailing currents. Many octocorals, like the tropical seafans, exhibit complex branching morphologies and grow large enough to form structure for numerous associated species. However, particular branching patterns should not be considered taxon- or taxa-specific. There are remarkable cases of convergent evolution where nearly identical morphologies (e.g. pinnate branching) in multiple octocorals differ in their modular (e.g., polyp and calyx) and ultrastuctural (e.g., sclerites) nature (Sanchez et al., 2003). The single most important character in octocoral identification is the microscopic calcareous sclerite (Bayer, 1956). A tissue sample containing these sclerites must be preserved to ensure genus and species level identifications. 2. Documenting your specimen in situ The most useful in-situ photo documentations include wide shots that illustrate community composition, medium shots of individual colonies to illustrate branching morphologies, close-ups of holdfast and attached substrate, and close-ups of extended polyps. Make note of colony size and branching variability, as rigorous documentation of these morphologies can be coupled with tissue samples to document within species variability. 3. Collecting A small well-preserved clipping from a colony is all that's necessary to isolate sclerites for traditional morphological identification and DNA for molecular study. In certain cases, e.g., vouchers and age studies, entire colonies, including holdfasts, should be collected. The holdfasts of Alcyonacea are known to exhibit unique chemical compositions. Entire colonies are useful if space allows, especially if the specimen is rare and/or unrepresented in collections. We recommend both wet and dry samples. The ideal wet samples will include well preserved polyps from branched segments less than 2 cm thick in duplicate solutions of 95% ethanol, fixed with 10% formalin if desired and another stored in a lysis buffer (a long-term alternative to DMSO) and later frozen for molecular study. Photography To keep these polyps extended on-deck, maintain the colony in its native seawater as long as possible. Many researchers relax their specimens in magnesium sulfate. Alternatively, place the colony in a bucket of refrigerated seawater, cut a small branch from the colony, and place this in a Petri dish of refrigerated seawater to examine and photograph the extended polyps through the oculus of a dissection microscope. Then photograph the larger colony with a sample number and scale. 4. Preserving your specimen to enhance long-term investigation and study For morphological vouchers and specimens for SEM analysis, both dried and ethanol preserved (95%) specimens are useful. Tissue fixation for morphological and histological study should be in 10% formalin, with preservation in 95% ethanol. For molecular studies tissue should be treated with DMSO or lysis buffer and preserved in liquid nitrogen or at -80°C. 5. Labeling The best labels are on paper inside the vial, in the preservative, clearly written in pencil. Paper should preferably be either 100% rag bond, Nalgene (TM) or Resistal (TM). Contact: University Products 517 Main Street, P.O. Box 101, Holyoke, MA 01041-0101. Write the date, cruise name, ship, researcher, station number, and sample number in clear block letters include geoposition (longitude and latitude), place name, depth in meters, related wet or dry samples, collection method, and substrate. Links NOAA Office of Ocean Exploration Website http://www.oceanexplorer.noaa.gov/explorations/04mountains/welcome.html Visiting a seamount is a special event, but returning to a previously visited seamount is truly rare. Three seamounts, Manning, Kelvin, and Bear, had spectacular gardens of octocorals. http://www.oceanexplorer.noaa.gov/explorations/03mex/welcome.html An interdisciplinary scientific team spends 12 days exploring deep-sea coral habitats in the Northern Gulf of Mexico. Deep water corals in the Gulf of Mexico (GOM) has been documented for some time, they may be widely distributed in this region that is heavily utilized by the oil and gas industry. http://oceanexplorer.noaa.gov/explorations/03nwhi/missions/leg2_summary/leg2_summary.html The 2003 Expedition to the Northwestern Hawaiian Islands studied the reproductive biology and population genetics of precious corals in the Hawaiian archipelago. This site contains first ever footage of an endangered monk seal foraging in precious coral beds. http://www.oceanexplorer.noaa.gov/explorations/02alaska/welcome.html The 2002 Exploring Alaska's Seamounts Expedition collected several excellent specimens from the Northeast Pacific Ocean. An article in the mission background describes some fascinating dispersal studies by Amy Baco-Taylor. She goes into greater detail in the July 7th log. The July 14th log details some of the problems with morphological classification in the Family Isididae. http://www.oceanexplorer.noaa.gov/explorations/03mountains/welcome.html The 2003 Mountains in the Sea Expedition also made some fascinating finds, and they detail sophisticated methods in the July 15 Daily Log by Scott France. NOAA Coral Reef Information System This portal favors Atlantic scleractinia, with links to myriad other online documents describing deep ahermatypic reefs. It includes lovely images, and a dense bibliography on Lophelia sp. and Oculina sp. Octocoral Research Center at the California Academy of Sciences This website created and maintained by Dr. Gary C. Williams at the California Academy of Sciences. The bibliography from Bayer is exhaustive, around 50 pages in its original form. The list of genera is extensive, and includes many photographs. Bibliography Alderslade, P. 1998. Revisionary systematics in the gorgonian family Isididae, with descriptions of numerous new taxa (Coelenterata: Octocorallia). Records of the Australian Museum suppl. 55: 1-359. Bayer, F.M. 1956. Octocorallia. In: Moore, R.C. (ed.), Treatise on invertebrate paleontology, Part F, Coelenterata: 166-231. Geological Society of America and University of Kansas Press, Lawrence. Bayer, F.M. 1981. Key to the Genera of Octocorallia Exclusive of the Pennatulacea (Coelenterata: Anthozoa), with diagnoses of new taxa. Proc. Biol. Soc. Wash. 943: 902-947. Bayer, F.M., M. Grasshoff. and J. Vossevelt. (eds.) 1983. Illustrated Trilingual Glossary of Morphological and Anatomical Terms Applied to Octocorallia. published by E. J. Brill, The Netherlands, 1983. Cairns S. D. and C. Messing, eds.. 2001. Bulletin of the Biological Society of Washington. Number 10. Commemorative Volume for the 80th Birthday of Frederick M. Bayer in 2001. Smithsonian Institution National Museum of Natural History. Cairns, S.D. 2002. Studies on western Atlantic Octocorallia (Coelenterata: Anthozoa). Part 1. The genus Chrysogorgia Duchassaing & Michelotti, 1864. Proceedings of the Biological Society of Washington 114: 746-787. Cairns, S.D. 1981. Marine Flora and Fauna of the Northeastern United States. Scleractinia. NOAA technical report NMFS Circular 438. Chave, E. and A. Malahoff. 1998. In Deeper Waters: Photographic Studies of Hawaiian Deep-sea Habitats and Life Forms. University of Hawaii Press, Honolulu, Hawaii. Etnoyer, P. (ed.), S. Cairns, J. A. Sanchez, J. Reed, S. Brooke , A. Baco-Taylor. In prep. "Deep-Sea Coral Collection Protocols". NOAA Technical Memorandum. Etnoyer P., and Morgan L. 2005. Habitat-forming deep-sea corals in the Northeast Pacific Ocean. In: Coldwater Corals and Ecosystems (eds. A Freiwald, JMRoberts), Springer Publishing House, Heidelberg, Germany. Fabricius K, Alderslade P. 2001. Soft Corals and Sea Fans: a comprehensive guide to Indo-Pacific coral reefs. Genin, A., P. K. Dayton, P. F. Lonsdale, and F. N. Spiess. 1986. Corals on seamount peaks provide evidence of current acceleration over deep-sea topography. Nature 322:59-61. Heifetz, J. 2002. Coral in Alaska: distribution, abundance, and species associations. Hydrobiologia 471: 19-28. Krieger, K. J. and B. L. Wing. 2002. Megafauna associations with deepwater corals (Primnoa spp.) in the Gulf of Alaska. Hydrobiologia 471: 82-90. Proceedings of the First and Second International Symposiums on Deep-sea Corals. Reed, J. K. 2002, Comparison of deep-water coral reefs and lithoherms off southeastern U.S.A. Hydrobiologia 471: 57-69. Report of the International Council for the Exploration of the Sea (ICES) Study Group on Deep-sea Corals. 2003. http://www.ices.dk/reports/ACE/2003/SGCOR03.pdf Roberts, S. and M. Hirshfield. 2004. Deep-sea coral, out of sight, but no longer out of mind. Frontiers of ecology and environment. 2: 123-130. Sánchez J.A.et al. 2003. Molecular phylogenetic analyses of shallow-water Caribbean octocorals. Marine Biology 142: 975-987 Sánchez J.A., H.R.Lasker & D.J. Taylor. 2003a. Phylogenetic analyses among octocorals (Cnidaria) according to mitochondrial and nuclear DNA sequences (lsu-rRNA 16S, and ssu-rRNA 18S) support two convergent clades of branching gorgonians. Molecular Phylogenetics & Evolution. 29(1): 31-42. Sánchez J.A., W. Zeng, V. R. Coluci, C. Simpson & H. R. Lasker. 2003. How similar are branching networks in nature? A view from the ocean: Caribbean gorgonian corals. Journal of Theoretical Biology. 222: 135-138. Sponaugle, S. and M. LaBarbera. 1991. Drag-induced deformation: a functional feeding strategy in two species of gorgonians. Journal of Experimental Marine Biology and Ecology 148:121-134. UN Status Report on Cold-water Coral Reefs. 2004. http://www.unep-wcmc.org/press/cold-water-coral-reefs/ Watling, L., and M. Risk, eds. 2002. Biology of Cold Water Corals. Vol. 471. Hydrobiologia. Kluwer Academic Publishers, Dordrecht, Netherlands.
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