White Gorgonian

White Gorgonian, Leptagorgia alba

White Gorgonian, Leptagorgia alba. Coral provided by the commercial fishermen in the greater Los Cabos area, Baja California Sur, July 2009. Size: 38 cm (15 inches) x 23 cm (9.1 inches).

Phylogeny: The White Gorgonian, Leptagorgia alba, (Duchassaing Michelotti, 1864) is an octocoral and a member of the Gorgoniidae Family of Gorgonians.   The Genus Leptagorgia is a large genus with ninety-four recognized species, and it is one of thirteen genera in this family. This species known in Mexico as either gorgonia blanca or látigo de mar. There are two accepted varieties within this species, Leptogorgia alba capensis and L. alba sulcata.

Morphology: The White Gorgonian has a small thin base with several long slender white stalks about 1 mm in diameter that taper to a pointed end that bear white polyps. The stalks are seldom branched. They reach 90 cm (35 inches) in length.

Habitat and Distribution: White Gorgonians are found attached to rocky reefs, subtidally to depths up to at least 70 m (230 feet).  In Mexican waters White Gorgonians are found along the entire Pacific Coast except for the west coast of the Baja Peninsula. They are found throughout the Sea of Cortez, being very common in Bahía de Los Ángeles, Baja California. They range south to Panama, including the Cocos and Galapagos Islands.

Diet: White Gorgonians are suspension feeders. The polyps use their eight tentacles to capture zooplankton, such as fish larva and amphipods, from the surrounding water.

Predators: White Gorgonians are eaten by the Gorgonian Spindle Slug,  Neosimnia avena.

Reproduction:   Reproduction in White Gorgonians is sexual with mature gametes being shed into the coelenteron and spawned through the mouth. The zygote develop into planktonic planula larva and metamorphosis begins with early morphogenesis of tentacles, septa, and pharynx before larval settlement on to the bottom substrate.

Ecosystem Interactions: White Gorgonians are known to host the Commensal Brittle Star, Ophiothela mirabilis. The gorgonian provides structure for the brittle star to climb up, into the nutrient rich current. The brittle stars do not appear to cause damage to the gorgonian.

Human Interactions:  White Gorgonians are currently of interest to scientists because they contain a series of novel biochemicals (thought to be present to ward off fish predators) that are being evaluated to kill malaria causing parasites in humans. Otherwise they have limited direct impact on human activities. From a conservation perspective they have not been formally evaluated however they are fairly common with a relatively wide distribution and should be consider to be of Least Concern.

Synonyms: Euplexaura lemasti, Leptogorgia rigida var. laevis, Litigorgia levis, and Lophogorgia alba.

Request for Help. This identification should be considered tentative due to the very remote location of the collection (Latitude 23oN and Longitude 110oW). I have found very little scientific focus on this area of the world and therefore supporting scientific documentation is not available. I welcome additional information on this coral from anyone who cares to contact us.