Giant split-pore sea rod (Plexaurella nutans)

Classification (WoRMS)

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

Accepted name: Plexaurella nutans · Authority: (Duchassaing & Michelotti, 1860) · Taxonomic status: accepted · AphiaID: 290819.

Synonyms and superseded combinations recorded for this taxon: Eunicea nutans Duchassaing & Michelotti, 1860; Plexaura friabilis Milne Edwards & Haime, 1957; Plexaurella affinis Bell, 1889; Plexaurella friabilis (Milne Edwards & Haime, 1857); Plexaurella fusifera Kunze, 1916; Plexaurella kunzei Kükenthal, 1924.

Source: World Register of Marine Species (WoRMS) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=290819 (CC BY 4.0). Accessed 2026-09-23.

Biology and life history (SeaLifeBase)

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

Depth range: 13–27 m · Habitat zone: sessile.

Source: SeaLifeBase species summary (SpecCode 43953) — https://www.sealifebase.se/summary/Plexaurella-nutans.html (CC BY-NC 3.0 — non-commercial use only). Accessed 2026-09-23.

Distribution and occurrence records (GBIF)

1,456 georeferenced occurrence records for Plexaurella nutans are published through GBIF from 24 countries or marine areas. The map above plots 63 distinct locations from a sample of 1,456 records, omitting 8 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: Puerto Rico (1,150); United States of America (198); Martinique (20); Colombia (15); Virgin Islands (U.S.) (12).

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

Source: GBIF Occurrence Search (taxonKey 2260924) — https://www.gbif.org/occurrence/search?taxon_key=2260924&has_coordinate=true (records CC0 / CC BY); WoRMS distribution records (MarineRegions) — https://www.marinespecies.org/aphia.php?p=taxdetails&id=290819 (CC BY 4.0); Natural Earth 110m basemap — https://www.naturalearthdata.com/ (public domain). Accessed 2026-09-23.

Description and natural history (Wikipedia)

Plexaurella nutans can grow to a height of over a metre (yard). It has thick cylindrical branches that occasionally fork and which are often slightly clubbed at the tips. These have a diameter of 10 to 15 cm. The polyps are rather large and protrude from round, oval or slit-shaped grooves in the cup-shaped calyces in the coral skeleton. Each of these calyces is on a slight mound giving the coral a dimpled surface. When the polyps are extended, as they usually are, they give the coral a fuzzy appearance. The colour of this coral is usually pale brown, grey or sometimes lavender.

Plexaurella nutans is an uncommon species and occurs at depths down to 50 m in the Caribbean Sea, the Bahamas and Florida. It is usually found on isolated patch reefs or on forereef slopes.

The polyps of Plexaurella nutans extend their tentacles to feed on zooplankton and other small invertebrates floating past. The food gathered is shared with neighbouring polyps via the gastrovascular cavity inside the coral's skeleton. After particles of liver marked with a radioactive tracer were fed experimentally to a single polyp, radioactivity was detected in tissues up to 11 cm away.

Plexaurella nutans is a zooxanthellate species of coral with large numbers of symbiotic dinoflagellates from the genus Symbiodinium living in its tissues. These are photosynthetic algae that provide nourishment to their host while benefiting from the coral's waste products. It was found experimentally that different species of Symbiodinium were found at different depths in Plexaurella nutans and other corals. If the corals' tissues were cultured in the laboratory, other species again became apparent, the growth of which was favoured by the laboratory environment. These must have been undetected in the tissues previously.

Source: Wikipedia: Plexaurella nutans — https://en.wikipedia.org/wiki/Plexaurella_nutans (CC BY-SA 4.0). Accessed 2026-09-23.

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