Octocorallians in very deep water
Subtidal octocorallians occurring as part of a mesophotic ecosystem in very deep water.
Disclaimer: Ecosystem type descriptions are based on biophysical attributes identified in Central Queensland through expert advice and supported by scientific literature. Not all ecosystem types are mapped based on current inventory, and many of the ecosystems described here may also occur in other parts of Queensland.
Octocorallians occurring as part of a mesophotic ecosystem in very deep water (greater than 30 metres) including the octocorallian genus Dendonepthya in deep holes on the sea floor (T. Stevens, pers. comm.). Octocorallia is a subclass of the class Anthozoa in the phylum Cnidaria, and include soft corals, gorgonians, sea whips, sea pens, sea fans and octocorals. Like some of the many other anthozoans, octocorallians are sessile (i.e. attached) polyp-bearing animals with a mobile larval phase. Octocorallians are distinguished by the eight (i.e. octo) tentacles in each polyp. Most octocorallians do not deposit a rigid calcium carbonate exoskeleton, and therefore tend to attach to reefs rather than contribute to reefal frameworks as per the reef building Scleractinian (hard) corals.
Mesophotic ecosystems are potentially refugia for species also found on shallow water ecosystems.
Mesophotic ecosystems are popular recreational fishing spots.
Benthic depth 'Very deep' greater than 30m
Structural macrobiota 'Soft coral – octocorallians'
Potentially Naturalness qualifiers are relevant. Being able to be shifted by mechanical action means that these ecosystems can be potentially modified by trawling or dredging.
Poorly known distribution in Queensland waters.
The following relates to distribution of this ecosystem type within the Central Queensland mapping area:
Not differentiated on Consolidation, these ecosystems may also fall within type 94 (undifferentiated coral not on consolidated in very deep water) and type 95 (undifferentiated coral on consolidated in very deep water). Other relevant attributes are Terrain morphology (channels, pits). Deep water ecosystems are only found in the south of the mapping region, in Hervey Bay. Other deep holes in the area that are along palaeochannels include Southern Gutters (to the south of 25 Fathom Hole) and African Gutters (to the north, potentially part of the Burnett palaeochannel). With further inventory, potentially may expand in range including other palaeochannels e.g. Fitzroy (north of Curtis).
Last updated: 22 July 2019
This page should be cited as:
Department of Environment, Science and Innovation, Queensland (2019) Octocorallians in very deep water, WetlandInfo website, accessed 1 February 2024. Available at: https://wetlandinfo.des.qld.gov.au/wetlands/ecology/aquatic-ecosystems-natural/estuarine-marine/descriptions/117/