Dead mans fingers (Alcyonium digitatum)

Classification (WoRMS)

Full classification as recorded by WoRMS: Kingdom: Animalia · Phylum: Cnidaria · Class: Octocorallia · Order: Malacalcyonacea · Family: Alcyoniidae · Genus: Alcyonium.

Accepted name: Alcyonium digitatum · Authority: Linnaeus, 1758 · Taxonomic status: accepted · AphiaID: 125333.

Synonyms and superseded combinations recorded for this taxon: Alcyonidium digitatum (Linnaeus, 1758); Lobularia digitata (Linnaeus, 1758).

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=125333 (CC BY 4.0). Accessed 2026-09-25.

Biology and life history (SeaLifeBase)

Measured values published by SeaLifeBase for Alcyonium digitatum. Only fields the database actually holds for this species are shown; these are database values, not aquarium guidance.

Habitat zone: sessile.

SeaLifeBase notes: Attached species (Ref. 3123). This organism prey on sea urchins, gastropods, bivalves, or crustaceans that crawl or swim into their grasp, indicating its carnivorous feeding type (Ref. 87872).

Source: SeaLifeBase species summary (SpecCode 43607) — https://www.sealifebase.se/summary/Alcyonium-digitatum.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-25.

Distribution and occurrence records (GBIF)

51,414 georeferenced occurrence records for Alcyonium digitatum are published through GBIF from 22 countries or marine areas. The map above plots 207 distinct locations from a sample of 3,000 records, omitting 92 inland records that carry an institution's coordinates rather than a collection site; it shows where the species has been observed and reported, not a modelled range.

Most records by country or area: United Kingdom of Great Britain and Northern Ireland (35,226); Sweden (6,679); Ireland (2,832); France (1,503); Isle of Man (1,044).

The full country table, WoRMS marine regions and the sampling notes are on this species' Distribution page.

Source: GBIF Occurrence Search (taxonKey 5185175) — https://www.gbif.org/occurrence/search?taxon_key=5185175&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=125333 (CC BY 4.0); Natural Earth 110m basemap — https://www.naturalearthdata.com/ (public domain). Accessed 2026-09-25.

Description and natural history (Wikipedia)

Dead man's fingers is a colonial coral forming clumps of yellow, white or cream-coloured fleshy masses of finger-like lobes. The surface layer include many sclerites which form a crust. The individual polyps are white and translucent, and project from the leathery surface when feeding, giving the colony a furry appearance.

Distribution and habitat

Dead man's fingers is found along the Atlantic coasts of north west Europe from Portugal to Norway, most recently being discovered in the uncharted waters of Jammerbugt bay off the north-west coast of Denmark by a 2020 seafloor mapping project led by explorer Klaus Thymann. The species also occurs in parts of Canada, northeastern coast of the United States, the Gulf of Maine and the Bay of Fundy and the northern waters of New Zealand. The polyps live in colonies attached to bedrock, boulders, stones and occasionally the shells of crabs and gastropods.

They are most plentiful in areas with strong water movement and where there is insufficient sunlight for algae to predominate. They are usually found in the sublittoral zone down to about fifty metres. This coral is common around the coasts of Britain and Ireland where Alcyonium glomeratum and Alcyonium hibernicum are also found but these are much rarer and misidentification is unlikely.

Biology

The colonies of dead man's fingers are nearly always either male or female, although a small number of hermaphrodite colonies are found. Colony growth occurs mainly in the first half of the year with the polyps becoming inactive in late summer, and the base tissue turning reddish or brownish due to the growth of algae and hydroids on the surface. At this time the gonads are developing and spawning occurs in December and January. Populations have been found to synchronize their gametogenesis and spawning activities.

Fertilisation takes place externally and the embryos float for a few days before developing into free swimming larvae. Most of these soon settle on a suitable substrate and new polyps develop but a few may remain in the zooplankton for some time and disperse over a wide area. Colonies have been known to live for twenty years.

The polyps feed at various times of the day with their tentacles extended. They are suspension feeders gathering plankton from the water with the help of cilia, and absorbing oxygen at the same time.

Source: Wikipedia: Alcyonium digitatum — https://en.wikipedia.org/wiki/Alcyonium_digitatum (CC BY-SA 4.0). Accessed 2026-09-25.