Abstract
Observations and collections made using remotely operated vehicles (ROV) outfit with high-definition video cameras on bathyal seamounts of the North Atlantic and North Pacific have revealed a bamboo coral (Octocorallia, Keratoisididae) with consistent and recognizable colony morphology: a long unbranched “stem” from which many vertically aligned branches arise in a single plane to produce the aspect of a tall candelabrum. Additional observations encountered colonies with only 3 branches arising from the central terminal node to produce the appearance of a standing trident. Genetic analyses suggested both colony morphologies (trident and candelabrum) to be the same species at different growth stages. Herein we formally describe this taxon, Tridentisis candelabrum n. gen. n. sp., erecting a new genus to accommodate the unique and distinctive colony morphology, and discuss morphological variation observed across the documented geographic range.
References
- Brugler, M.R. & France, S.C. (2008) The mitochondrial genome of a deep-sea bamboo coral (Cnidaria, Anthozoa, Octocorallia, Isididae): genome structure and putative origins of replication are not conserved among octocorals. Journal of Molecular Evolution, 67, 125–136. https://doi.org/10.1007/s00239-008-9116-2
- Etnoyer, P.J. (2008) A new species of Isidella bamboo coral (Octocorallia: Alcyonacea: Isididae) from northeast Pacific seamounts. Proceedings of the Biological Society of Washington, 121 (4), 541–553. https://doi.org/10.2988/08-16.1
- France, S.C. (2007) Genetic analysis of bamboo corals (Cnidaria: Octocorallia: Isididae): does lack of colony branching distinguish Lepidisis from Keratoisis?. Bulletin of Marine Science, 81 (3), 323–333. [https://www.ingentaconnect.com/contentone/umrsmas/bullmar/2007/00000081/00000003/art00003]
- Ganguly, U. & France, S.C. (2024) Expanded distribution and a new genus for rock-inhabiting sea pens (Cnidaria, Anthozoa, Octocorallia, Pennatuloidea). Zootaxa, in press.
- Heestand Saucier, E. (2016) Phylogenetic studies of the deep-sea bamboo corals (Octocorallia: Isididae: Keratoisidinae). PhD dissertation, University of Louisiana, Lafayette, Louisiana, 206 pp.
- Heestand Saucier, E., France, S.C. & Watling, L. (2021) Toward a revision of the bamboo corals: Part 3, deconstructing the Family Isididae. Zootaxa, 5047 (3), 247–272. https://doi.org/10.11646/zootaxa.5047.3.2
- Hogan, R.I., Hopkins, K., Wheeler, A.J., Allcock, A.L. & Yesson, C. (2019) Novel diversity in mitochondrial genomes of deep-sea Pennatulacea (Cnidaria: Anthozoa: Octocorallia). Mitochondrial DNA, Part A, 30 (6), 764–777. https://doi.org/10.1080/24701394.2019.1634699
- Kennedy, B.R., Cantwell, K., Malik, M., Kelley, C., Potter, J., Elliott, K., Lobecker, E., Gray, L.M., Sowers, D., White, M.P. & France, S.C. (2019) The unknown and the unexplored: Insights into the Pacific deep-sea following NOAA CAPSTONE expeditions. Frontiers in Marine Science, 6, 480. https://doi.org/10.3389/fmars.2019.00480
- Lapointe, A. & Watling, L. (2022) Towards a revision of the bamboo corals (Octocorallia): Part 5, new genera and species of Keratoisididae from the Tasmanian deep sea. Zootaxa, 5168 (2), 137–157. https://doi.org/10.11646/zootaxa.5168.2.3
- McFadden, C.S., Benayahu, Y., Pante, E., Thoma, J.N., Nevarez, P.A. & France, S.C. (2011) Limitations of mitochondrial gene barcoding in Octocorallia. Molecular ecology resources, 11 (1), 19–31. https://doi.org/10.1111/j.1755-0998.2010.02875.x
- Morrissey, D., Gordon, J.D., Saso, E., Bilewitch, J., Taylor, M.L., Hayes, V., McFadden, C.S., Quattrini, A.M. & Allcock, A.L. (2023) Bamboozled! Resolving deep evolutionary nodes within the phylogeny of bamboo corals (Octocorallia: Scleralcyonacea: Keratoisididae). Molecular Phylogenetics and Evolution, 188, 107910. https://doi.org/10.1016/j.ympev.2023.107910
- NOAA Ocean Exploration (2023) NOAA Ocean Exploration Data Atlas, Version 1.0.4, Available from: https://www.ncei.noaa.gov/maps/ocean-exploration-data-atlas/ (accessed 9 June 2023)
- Pante, E., France, S.C., Couloux, A., Cruaud, C., McFadden, C.S., Samadi, S. & Watling, L. (2012) Deep-sea origin and in-situ diversification of chrysogorgiid octocorals. PLoS One, 7 (6), e38357. https://doi.org/10.1371/journal.pone.0038357
- Pante, E., France, S.C., Gey, D., Cruaud, C. & Samadi, S. (2015) An inter‐ocean comparison of coral endemism on seamounts: the case of Chrysogorgia. Journal of Biogeography, 42 (10), 1907–1918. https://doi.org/10.1111/jbi.12564
- van der Ham, J.L., Brugler, M.R. & France, S.C. (2009) Exploring the utility of an indel-rich, mitochondrial intergenic region as a molecular barcode for bamboo corals (Octocorallia: Isididae). Marine Genomics, 2 (3–4), 183–192. https://doi.org/10.1016/j.margen.2009.10.002
- Watling, L., Heestand Saucier, E. & France, S.C. (2022) Towards a revision of the bamboo corals (Octocorallia): Part 4, delineating the family Keratoisididae. Zootaxa, 5093 (3), 337–375. https://doi.org/10.11646/zootaxa.5093.3.4
- Zapata, F., Goetz, F. E., Smith, S.A., Howison, M., Siebert, S., Church, S.H., Sanders, S.M., Ames, C.L., McFadden, C.S., France, S.C., Daly, M., Collins, A.G., Haddock, S.H.D., Dunn, C.W. & Cartwright, P. (2015) Phylogenomic analyses support traditional relationships within Cnidaria. PLoS ONE, 10 (10), e0139068. https://doi.org/10.1371/journal.pone.0139068