Red Sea Plume, Asparagopsis taxiformis

Red Sea Plume, Asparagopsis taxiformis. Sea plum photographed in its native environment off Luigi within the Bahía de Loreto National Park, Baja California Sur, March 2025. Photograph and identification courtesy of Dr. Jake Turin, Albuquerque, New Mexico.

Phylogeny: The Red Sea Plume, Asparagopsis taxiformis ((Delile) Trevisan de Saint-Léon, 1845), is a Red Algae that is a member of the Bonnemaisoniaceae Family of Sea Plumes. The Asparagopsis genus is one of six genera in the Bonnemaisoniaceae Family, and there are three species in the Asparagopsis genus. They are known in Mexico as Alga Plumero Rojo and Pluma de mar Roja. The genus name Aseragopsis comes from the Greek words mean “appearing like asparagus”. This refers to the plants feathery plume-like structure. The species name taxiformis comes from Latin and means “yew tree-like”, referring to this plant’s two vertical rows of flattened leaves.

Morphology: The Red Sea Plume have erect thalli that are greenish to red in color that are feathery or plumose, originated from a creeping stolon and attached by a rhizoid to the solid substrate. The central axis is terete (circular) with branches at its upper half and to two-thirds. The feathery or plumose branches are composed of numerous fine and delicate smaller branches which are densely deposited around an axis. Their cyrstocarps (fruit) are distinctive globes in shape and bright red in color found at the tips of the smaller branches. The Red Sea Plume reach a maximum of 13 cm (5.1 inches) in height. They have a haplodiplontic life cycle alternating between a multicellular haploid or gametophyte stage and a diploid or sporophyte stage with each phase being morphologically distinct. Both stages undergo mitosis to grow, with meiosis occurring in the sporophyte to produce spores, and mitosis in the gametophyte to produce gametes, showcasing alternation of generations with distinct phases.

Habitat and Distribution: The Red Sea Plume has a global cosmopolitan distribution and is found in all Mexican waters of the Atlantic and Pacific Oceans. The Red Sea Plume is found attached to solid substrate on reef and rocky shores that are exposed to moderately strong water movement at depths up to 14 m (46 feet). They also attach themselves to coral, mangrove roots, other plants, and rocks. During their gametophyte stage they grow on rock faces and compacted gravel and sand.

Reproduction: Asparagopsis taxiformis has a complex triphasic life cycle, reproducing sexually (gametophyte to carposporophyte to tetrasporophyte) and asexually (fragmentation/rhizomes), with distinct macroscopic stages: a prominent, branching gametophyte (male/female) and a smaller, filamentous tetrasporophyte, with both stages able to propagate vegetatively, contributing to its widespread success. Reproduction involves carpospores from the gametophyte leading to the tetrasporophyte, and tetraspores from the tetrasporophyte forming new gametophytes, often influenced by light, nutrients, and temperature.

Diet: The Red Sea Plume possesses zooxanthellae that use photosynthesis to create food (amino acids, fats, sugars) from sunlight, water and coral waste carbon dioxide.

Conservation: From a conservation perspective the Red Sea Plume has not been formally evaluated. It has become highly invasive in some parts of the world. The Red Sea Plume is utilized by humans as a food being a component of limu poke, popular in Hawaii. and in medicine possessing antibiotic and antimicrobial properties. This seaweed has been shown to possess bioactive natural products, bromoform, dibromochloromehane and dicholoromethane, which, when added to the diets of ruminant livestock in very small amounts, can eradicate methane emissions. The production of Asparagopsis taxiformis via aquaculture is currently being heavily pursued by the academic community and by several global start-up companies using various approaches to make this seaweed available to the livestock industry.

Synonyms: Asparagopsis sanfordiana.