Madrepora oculata, also called zigzag coral, is a stony coral that is found worldwide outside of the polar regions, growing in deep water at depths of 50 to at least 1500 meters.[1] It was first described by Carl Linnaeus in his landmark 1758 10th edition of Systema Naturae.[2] It is one of only 12 species of coral that are found worldwide, including in Subantarctic oceans.[3] In some areas, such as in the Mediterranean Sea and the Northeast Atlantic Ocean, it dominates communities of coral.[4] Due to their similar distribution and taxonomic relationship, M. oculata is often experimentally compared to related deep sea coral, Lophelia pertusa.[5]

Madrepora oculata
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Cnidaria
Class: Hexacorallia
Order: Scleractinia
Family: Oculinidae
Genus: Madrepora
Species:
M. oculata
Binomial name
Madrepora oculata
Synonyms
List
  • Amphihelia moresbyi Alcock, 1898
  • Cyathohelia formosa Alcock, 1898
  • Lophohelia investigatoris Alcock, 1898
  • Lophohelia tenuis Moseley, 1881
  • Madrepora alcocki Faustino, 1927
  • Madrepora candida (Moseley, 1881)
  • Madrepora kauaiensis Vaughan, 1907
  • Madrepora tenuis (Moseley, 1881)
  • Madrepora venusta Milne Edwards & Haime, 1850
  • Madrepora vitiae Squires & Keyes, 1967

Description edit

The species is quite variable in its tendency to branch, its texture, and its color, even within specimens of the same coral colony. It is bushy, growing in small colonies that form thickets, creating matrices that are fan-shaped and about 30 to 50 cm high. It has thick skeletal parts that grow in a lamellar pattern.[6] The coral has been found to grow 3–18 mm per year with the addition of about 5 polyps a year. This growth rate has been found to be comparable to related deep sea coral, Lophelia pertusa.[7]

As its skeleton is fragile and unable to sustain a large framework, it is usually found among stronger coral, such as Lophelia pertusa and Goniocorella dumosa, that offer protection. In areas where it dominates, it is usually found in rubble and debris rather than in coral reefs.[4]

The species is a bank-building coral, meaning it tends to build upwards, in a linear fashion. Bank reefs are built by non-photosynthetic calcifiers, as they occur at depths sunlight cannot reach.[8]

Madrepora oculata produces large amounts of extracellular mucus, which acts in a protective capacity to shield the coral skeleton from being bored into by endolithic organisms.[6]

Distribution & Habitat edit

M. oculata is distributed worldwide, but is most densely concentrated in the northern Atlantic Ocean, southern and western Pacific Ocean, and the Mediterranean Sea.[9] While temperatures range from 5-9 °C in the northern Atlantic Ocean, temperatures reach 11-13 °C in the Mediterranean. Though the species is distributed through many temperatures, it has been shown experimentally that the species does not display thermal acclimation in both respiration and calcification. Alternatively, L. pertusa does exhibit thermal acclimation in respiration and calcification, indicating species-specific diversity between deep sea corals.[10] While M. oculata does not exhibit thermal acclimation, has been experimentally shown to have a high resistance to pH in terms of skeletal growth and calcification.[11]

Reproduction edit

The species is known to perform continuous reproduction, releasing fewer but larger oocytes when compared to seasonal reproducers like Desmophyllum pertusum. They are broadcast spawners, meaning they release their gametes into open water for fertilization. Madrepora oculata are also gonochoristic, as they possess different gametes for different sexes.[12]

There has been some evidence of seasonality reproduction for the species, although this is hypothesized to be due to environmental signals such as periods of increased primary productivity (allowing for more particulate organic carbon availability in the benthos) rather than true seasonality.[13]

Hypertrophy edit

The first instances of possible cancer in coral were reported in a species of Madrepora in Hawaiian waters in which hypertrophied corallites were noted. Similarly hypertrophied corallites were described in colonies of Madrepora oculata near northwestern Australia and Japan, as well as in the Formosa Strait and other areas, but have never been confirmed. A recent provisional reinterpretation is that these abnormal corallites are a form of internal gall, an abnormal swelling or growth caused by infection by a parasite, rather than a classical neoplasm.[14]

References edit

  1. ^ Hansson, Lina; Agis, Martin; Maier, Cornelia; Weinbauer, Markus G. (2009). "Community composition of bacteria associated with cold-water coral Madrepora oculata: within and between colony variability". Marine Ecology Progress Series. 397: 89–102. doi:10.3354/meps08429. ISSN 0171-8630. JSTOR 24874291.
  2. ^ Covadonga Orejas, Christine Ferrier-Pagès, Stéphanie Reynaud, Georgios Tsounis, Denis Allemand, Josep Maria Gili, "Experimental comparison of skeletal growth rates in the cold-water coral Madrepora oculata Linnaeus, 1758 and three tropical scleractinian corals," Journal of Experimental Marine Biology and Ecology, 405(1-2), 2011, p. 1-5. https://doi.org/10.1016/j.jembe.2011.05.008.
  3. ^ "NOAA's Coral Reef Information System (CoRIS) - Deep Water Corals". coris.noaa.gov. Archived from the original on 2010-02-21. Retrieved 2009-10-30.
  4. ^ a b "What is Madrepora oculata?" (PDF). Deepsea Conservation for the United Kingdom Project. Retrieved 2009-10-30.
  5. ^ Arnaud-Haond, S.; Van den Beld, I.M.J.; Becheler, R.; Orejas, C.; Menot, L.; Frank, N.; Grehan, A.; Bourillet, J.F. (November 2017). "Two "pillars" of cold-water coral reefs along Atlantic European margins: Prevalent association of Madrepora oculata with Lophelia pertusa, from reef to colony scale". Deep Sea Research Part II: Topical Studies in Oceanography. 145: 110–119. doi:10.1016/j.dsr2.2015.07.013. ISSN 0967-0645.
  6. ^ a b Reitner, Joachim. Calcifying extracellular mucus substances (EMS) of Madrepora oculata. www.springerlink.com. doi:10.1007/3-540-27673-4_38. ISBN 9783540241362, 9783540276739.
  7. ^ Orejas, C.; Gori, A.; Gili, J. M. (2008-06-01). "Growth rates of live Lophelia pertusa and Madrepora oculata from the Mediterranean Sea maintained in aquaria". Coral Reefs. 27 (2): 255. doi:10.1007/s00338-007-0350-7. ISSN 1432-0975.
  8. ^ Altuna, Álvaro (2013). "Scleractinia (Cnidaria: Anthozoa) from ECOMARG 2003, 2008 and 2009 expeditions to bathyal waters off north and northwest Spain (northeast Atlantic)". Zootaxa. 3641 (2): 101–128. doi:10.11646/zootaxa.3641.2.1. ISSN 1175-5326. PMID 26287072.
  9. ^ Orejas, Covadonga; Wienberg, Claudia; Titschack, Jürgen; Tamborrino, Leonardo; Freiwald, André; Hebbeln, Dierk (2021-07-26). "Madrepora oculata forms large frameworks in hypoxic waters off Angola (SE Atlantic)". Scientific Reports. 11 (1): 15170. doi:10.1038/s41598-021-94579-6. ISSN 2045-2322. PMC 8313707. PMID 34312452.
  10. ^ Naumann, Malik S.; Orejas, Covadonga; Ferrier-Pagès, Christine (January 2014). "Species-specific physiological response by the cold-water corals Lophelia pertusa and Madrepora oculata to variations within their natural temperature range". Deep Sea Research Part II: Topical Studies in Oceanography. 99: 36–41. doi:10.1016/j.dsr2.2013.05.025.
  11. ^ Movilla, Juancho; Gori, Andrea; Calvo, Eva; Orejas, Covadonga; López-Sanz, Àngel; Domínguez-Carrió, Carlos; Grinyó, Jordi; Pelejero, Carles (2013-12-31). "Resistance of Two Mediterranean Cold-Water Coral Species to Low-pH Conditions". Water. 6 (1): 59–67. doi:10.3390/w6010059. hdl:2445/98901. ISSN 2073-4441.
  12. ^ Chemel, M.; Meistertzheim, A. L.; Mouchi, V.; Lartaud, F. (2023-05-01). "Reproductive biology of the two main reef-building cold-water coral species (Desmophyllum pertusum and Madrepora oculata) in the Mediterranean Sea". Deep Sea Research Part I: Oceanographic Research Papers. 195: 103984. doi:10.1016/j.dsr.2023.103984. ISSN 0967-0637.
  13. ^ Waller, Rhian G.; Tyler, Paul A. (2005-11-01). "The reproductive biology of two deep-water, reef-building scleractinians from the NE Atlantic Ocean". Coral Reefs. 24 (3): 514–522. doi:10.1007/s00338-005-0501-7. ISSN 1432-0975.
  14. ^ Mark J. Grygier, Stephen D. Cairns (January 4, 1996). "Suspected neoplasms in deep-sea corals (Scleractinia: Oculinidae: Madrepora spp.) reinterpreted as galls caused by Petrarca madreporae n. sp. (Crustacea: Ascothoracida: Petrarcidae)" (PDF). Diseases of Aquatic Organisms. Retrieved 2009-10-30.

External links edit