Desmophyllum dianthus is assessed as Least Concern. It is a cosmopolitan solitary coral /pseudocolonial species, with a broad distribution, occurs between 8–3,380 m depth, and has a broadly defined niche. It is associated with species that are in continuous decline: the broad distribution for D. dianthus means it also overlaps with a number of protected areas globally which could act as reservoirs for the species. For D. dianthus, regional decline is likely, such as has been assessed in the Mediterranean (where it was classified as Endangered), but it is not currently at a level that will impact the population at a global scale.

Desmophyllum dianthus is a cosmopolitan solitary coral species, occurring in every ocean. It is found at depths from around 8–3,380 m, with most records between 200–2,000 m.

Desmophyllum dianthus is found in cold-water habitats across the globe. It grows on hard substrates ranging from D. pertusum reefs, to canyon walls, to boulders and has even been found growing on plastic debris (Bergami et al. 2021). Limited data are available for reproduction for this species across its entire range, but studies in an isolated Pacific fjord population demonstrated that the species is a dioecious, broadcast spawning species, with highly seasonal reproduction, and high fecundity (Feehan et al. 2019).

Desmophyllum dianthus is long lived (up to 200 years) and slow growing, with a growth rate of 0.5–2 mm per year (Adkins et al. 2004, Risk et al. 2002). Higher growth rate has also been recorded in Chilean fjords, with maximum growth of 2.2–10 mm per year (Jantzen et al. 2013). They are thus slow to recover from damage. This species is gonochoric (Feehan et al. 2019). In Chile, it has a seasonal reproductive cycle, beginning gamete production in early September (spring) and spawning a year later in August (Austral winter). Fecundity is high compared to other deep-sea scleractinians, ranging from ~2,400 to 172,000 oocytes per polyp (Feehan et al. 2019).

This species also contributes to the reef framework as aggregated colonies or “clumps of specimens” (Cairns 1982). In Chile, D. dianthus corals form extensive banks below 20 m, which provide habitat for numerous associated species (Försterra et al. 2016). Also in Chile, D. dianthus has been found in an unusual symbiosis with the phototrophic alga Ostrobium quecketii (Försterra and Häussermann 2008).

Desmophyllum dianthus is resilient to the effect of ocean acidification in laboratory-based experiments (Carreiro-Silva et al. 2014) and transplant studies showing no difference in growth or fitness (Beck et al. 2022).

Its broad geographic and depth distribution mean that D. dianthus is subjected to a variety of threats. It is threatened by fishing activity. The coral framework is easily destroyed by heavy trawl doors and the bobbins that weight the ground rope of benthic trawls. It has been recorded in bycatch from numerous regions. In New Zealand, it has been the most frequently recorded protected coral species in bycatch (Tracey et al. 2019). Another emerging concern for hard coral species is ocean acidification, which will make it more difficult for corals to sequester and maintain their calcium carbonate skeleton. A regional assessment for D. dianthus in the Mediterranean listed this species as regionally Endangered.

Specifically in Chile, where the population is large, the construction of the austral road could greatly affect the populations due to increasing sediment load. Sediment load increase is a threat that is occurring in many coastal areas.

This species is protected by CITES Appendix II.

Desmophyllum dianthus is often associated with reef building scleractinians such as D. pertusum, and clear evidence of damage to and destruction of D. pertusum reefs has led to legislation to protect these habitats. The occurrence and conservation of D. pertusum reefs can be taken as a proxy for D. dianthus; however, D. dianthus is more widespread. Existing protection for part of the D. pertusum reefs provides protection for some populations of D. dianthus.

Within the OSPAR Maritime Area, over 70% of D. pertusum occurrences lie outside protected areas (OSPAR 2022), but with considerable regional variation and with relatively less protection in Arctic waters. Approximately 40% of D. pertusum habitat predicted by a model covering the UK and Irish margins was found to be within a Marine Protected Area (MPA), but this varied from 84% in UK waters to 4% in Irish waters (Howell et al. 2022). The number of known occurrences of the habitat has increased over the last 10 years due to targeted research. Newly discovered reefs can be vulnerable, although 'move on' rules may be implemented by Regional Fisheries Management Organisations (OSPAR 2022).

Accurate distribution maps of scleractinian reefs are required to better assess threats to D. dianthus from human activities, and monitoring of species occurrence as well as the extent of the reef habitat for further declines are required.