| The area of Bahía Inútil, in the Magallanes region, continues to reveal its astonishing marine biodiversity. A recent publication led by Chilean and Argentine specialists documented for the first time in Chile the presence of the brown macroalga Microzonia velutina in the underwater environment of the Isla Grande de Tierra del Fuego, adding a new species to the diverse phycological flora of our country and expanding its distribution range on the Argentine Atlantic coast.
The discovery occurred in the context of the joint expedition carried out in March 2025 between researchers from the Marine Program of the Fundación Rewilding Chile and CADIC-CONICET of Ushuaia, as well as professionals in charge of underwater and terrestrial filming, with the aim of characterizing the biodiversity associated with Fuegian forests of Macrocystis pyrifera (kelp or sargassum).
To this end, exploratory dives were conducted between 3 and 6 meters at three sampling sites, two in Bahía Inútil, the Chilean side of the Isla Grande de Tierra Argentino, and one in the Argentine sector of Bahía Aguirre, in the Península Mitre.
Regarding the importance of the record, Mathias Hüne, Director of the Marine Program of Rewilding Chile, highlighted:
“In the context of the climate crisis, expanding knowledge about marine biodiversity in high latitudes is essential to support conservation strategies and reinforces the biogeographic value of Tierra del Fuego and particularly of Bahía Inútil, as a key area for subantarctic diversity.”
The analysis of the expedition results was published in the prestigious German journal Botánica Marina -the most classic in its field- as “New records of Microzonia velutina (Syringodermatales, Ochrophyta) in Isla Grande de Tierra del Fuego in the sub-Antarctic region”.
Its authors are Mauricio Palacios, associate researcher of the Fundación Rewilding Chile; Julieta Kaminsky, from CADIC CONICET of Ushuaia; Mathias Hüne, director of the Marine Program of Rewilding Chile; ecologists and taxonomists Erasmo Macaya from the University of Concepción and Alicia Boraso, a reference in the study of macroalgae in Argentina, from the National University of Patagonia, along with underwater photographer Mariano Rodríguez from the National University of Tierra del Fuego.
In all sampling points, Microzonia velutina was observed as part of the understory flora on rocky substrates under kelp forests.
Unlike the elongated kelps, whose underwater forests can measure up to 80 meters, this small macroalga, fan-shaped, does not exceed 3 centimeters in height and stands out for its olive-brown color with iridescent pigmentation on the edges.
“It is not easy to see, because it is very small and one might think it could be a fungus like those found in terrestrial forests, but it is a macroalga. To find it, you have to look for it intentionally, it is not easy to see, but when we find it, its fan shape is very characteristic, with small lines and it grows very close to the rock substrate,” indicates Julieta Kaminsky, researcher at CADIC-CONICET of Ushuaia.
“In general terms, it is a relatively uncommon and little-known species, more typical in New Zealand, but not abundant, with only two records in the southern hemisphere, particularly on the Atlantic coast of Argentina,” explains Mauricio Palacios, associate researcher of Rewilding Chile. “We know little about its external morphology, its life cycle, its habits, why it is here and not elsewhere, etc.,” he adds.
During the expedition, complete thalli of the small macroalga were collected and identified based on external and internal morphology, “with the naked eye,” as Julieta Kaminsky specifies to describe the method.
“Then we make small cuts that allow us to observe under the magnifying glass or optical microscope and from different characteristics that are specific or particular and comparing with other specimens that resembled those from Argentina and other parts of the world, we can determine which species it corresponds to,” she adds. Once identified, three specimens were preserved in the herbarium maintained by Rewilding Chile. |
