Paramuricea clavata, the violescent sea-whip, is a species of colonial soft coral in the family Plexauridae. It is found in shallow seas of the north-eastern Atlantic Ocean and the north-western Mediterranean Sea as well as Ionian Sea. This species was first described by the French naturalist Antoine Risso in 1826.

Paramuricea clavata
Paramuricea clavata with polyps expanded
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Cnidaria
Class: Octocorallia
Order: Alcyonacea
Family: Plexauridae
Genus: Paramuricea
Species:
P. clavata
Binomial name
Paramuricea clavata
(Risso, 1826) [1]

Description

edit

P. clavata has a branching structure forming a fan-shaped colony in a single plane. The stem and branches are stiffened by gorgonin, a complex protein that produces a horny skeleton. The coenenchyme, a thin living layer of cells, covers the skeleton and the polyps protrude from this, each with eight feeding tentacles surrounding a central mouth. The polyps are up to 10 mm (0.4 in) high and the whole colony up to one m (3 ft) high and 1 m across. The colour is usually red, but may be partly yellow.[2]

Distribution and habitat

edit

The violescent sea-whip is native to the coasts of Spain and Portugal in the eastern Atlantic Ocean, and to the western Mediterranean Sea. It grows on reefs with its base buried in the sediment at depths between 10 and 100 m (33 and 328 ft), but usually between 15 and 40 m (49 and 131 ft). It is considered to be an ecosystem engineer, as its presence alters the flow of water, changes sedimentation rates, and alters the distribution of nutrients, thus affecting many organisms in its vicinity.[3]

Biology

edit

P. clavata is a filter feeder, the polyps extending their tentacles to catch food particles floating past. Its diet includes copepods, diatoms, dinoflagellates, ciliates, and organic carbon particles in suspension.[4]

Each colony is either male or female. Sperm is liberated into the sea by the male colonies and fertilisation occurs on the surface of the female colonies. The embryos are brooded there before being released as planula larvae into the water column. The larvae are photophobic and soon settle on the seabed. Once there, they develop into polyps and start secreting gorgonin to form the skeleton. Further growth of the colony is by budding of new polyps. Some new colonies may be formed from fragments that become detached from existing colonies.[5] P. clavata is a slow-growing species and colonies probably live for well over 50 years.[6][7]

References

edit
  1. ^ van Ofwegen, Leen (2014). "Paramuricea clavata (Risso, 1826)". WoRMS. World Register of Marine Species. Retrieved 2014-12-16.
  2. ^ Pontes, Miquel (2012-12-31). "La gorgonia roja" (in Spanish). Mare Nostrum. Retrieved 2014-12-16.
  3. ^ Jones, Clive G.; Lawton, John H.; Shachak, Moshe (1994). "Organisms as ecosystem engineers". Oikos. 69 (3): 373–386. doi:10.2307/3545850. JSTOR 3545850.
  4. ^ Ribes, M.; Coma, R.; Gili, J.M. (1999). "Heterogeneous feeding in benthic suspension feeders:the natural diet and grazing rate of the temperate gorgonian Paramuricea clavata (Cnidaria:Octocorallia) over a year cycle". Marine Ecology Progress Series. 183: 125–137. Bibcode:1999MEPS..183..125R. doi:10.3354/meps183125.
  5. ^ Coma, Rafel; Ribes, Marta; Zabala, Mikel; Gili, Josep-Maria (1995). "Reproduction and cycle of gonadal development in the Mediterranean gorgonian Paramuricea clavata". Marine Ecology Progress Series. 117 (1/3): 173–183. Bibcode:1995MEPS..117..173C. doi:10.3354/meps117173. JSTOR 44634829.
  6. ^ Cristina Linares; Daniel F. Doak; Rafel Coma; David Díaz & Mikel Zabala (2007). "Life history and viability of a long-lived marine invertebrate: The octocoral Paramuricea clavata" (PDF). Ecology. 88 (4): 918–928. doi:10.1890/05-1931. hdl:10261/74959. PMID 17536708.
  7. ^ Shulgin, Alexander (1997). TIHKAL: The Continuation. Transform Press. ISBN 9780963009692.
edit