Austera Gorgonian, Muricea austera
Austera Gorgonian, Muricea austera. Underwater photograph taken in the greater Cabo San Lucas area, Baja California Sur, March 2018. Photograph courtesy of Bob Hillis, Ivins, Utah. Identification courtesy of Greg Timms, youtube.com/@Coralmasterdives-PuertoVallarta/videos.
Austera Gorgonian, Muricea austera. Underwater photographs taken at various locations Bahía de Banderas, Puerto Vallartqa Jalisco, July 2026. Photographs and identifications courtesy of Greg Timms, youtube.com/@Coralmaster-divesPuertoVallarta/videos.
Phylogeny: The Austera Gorgonian, Muricea austera (Verrill, 1869), is an octocoral member of the Plexauridae Family of Gorgonians. The Muricea Genus is one of five genera in the Plexauridae Family and there are thirty-three species in the Muricea Genus. The species name austera comes from the Latin adjective meaning “dry”, “harsh”, “severe”, or “bitter”. They are also known as the Austera Sea Fan and in Mexico as the Gorgonia Austera.
Morphology: The Austera Gorgonian is a colonial organism that is composed of thousands of individual polyps. Gorgonians have flexible branches that often sway with the currents, unlike stony corals. Austera Gorgonians may grow as a single finger-like branch, or multiple branches in a plane or bush-like structure. The branches can bifurcate (fork) up to six times. In some cases the colony holdfast grows along the substrate, sending up branches the entire length. The branches range in diameter from 6 mm (0.24 inches) to 10 mm (0.39 inches), and are reddish-brown with yellow to orange polyps. The polyps are flower-like, with eight tentacles around the oral disk. The individual polyp cups (calyces) can reach 2 mm in height. Austera Gorgonian colonies reach a maximum of around 20 cm (7.9 inches) in height.
Habitat and Distribution: Austera Gorgonians are found attached to hard surfaces such as coral, pilings, rocks, and wreckage, in clear, moderately current-swept, areas. They live at depths between the lowest intertidal zone and 30 m (98 feet), though some sources push the maximum depth to 200 m (656 feet). Austera Gorgonians are a tropical Eastern Pacific species that are found in all Mexican waters of the Pacific Ocean with the exception that they are absent from the west coast of the Baja Peninsula, and the north of La Paz, Baja California Sur in the Sea of Cortez.
Diet: The Austera Gorgonian is a sessile suspension feeder that captures drifting food in the water column by individual polyps with small tentacles. These nutrients will reach all members of the colony through channels in the gastrovascular cavity. The Austera Gorgonian’s diet consists of water-borne prey like eggs, coral spawn, larvae and plankton. They are an azooxanthellate coral.
Predation: Documentation of Austera Gorgonian predators is very limited. Other similar species in the Muricea Genus are preyed upon by butterfly fishes, damselfishes, gastropods and sea stars.
Reproduction: Austera Gorgonians can reproduce asexually through budding and sexually through spawning. During spawning, mass amounts of eggs and sperm are released into the water and fuse into gametes. The larvae will eventually settle on a substrate and begin to form a polyp. From here, a colony grows through cloning (asexual reproduction). Spawning usually takes place in early summer.
Ecosystem Interactions: Austera Gorgonians are a poorly studied and documented species. Their parasitic, commensal, and mutualistic relationships have not been formally documented. Other species in this genus have microbial corallicolids living in their cells. It is thought that these corallicolids are parasitic, but they may be commensal. Austera Gorgonians use a mixture of diterpenes and lipids to chemically deter marine snow, bacteria, and algae from settling on the colony, causing suffocation. Many invertebrates species, such as amphipods, copepods, polychaetes, and brittle stars find shelter in the branches of Austera Gorgonians.
Human Interactions: Austera Gorgonians have a very limited impact on human activities. From a conservation perspective they have not been formally evaluated. Regional threats to the species include coastal development, water pollution, and increased sedimentation from coastal activities.
Synonyms: None