New record of Sargassum filicinum Harvey (Fucales, Phaeophyceae) in the Pacific Coast of Mexico

doi:2007.22.1.17

Algae > Volume 22(1); 2007 > Article

Algae 2007;22(1): 17-21. doi: https://doi.org/10.4490/algae.2007.22.1.017

Luis E. Aguilar-Rosas¹^*, Raúl Aguilar-Rosas², Hiroshi Kawai³, Shinya Uwai³ and Enrique Valenzuela-Espinoza¹

¹Instituto de Investigaciones Oceanológicas, Universidad Autónoma de Baja California, Apartado Postal 453, 22830, Ensenada, Baja California, México
²Facultad de Ciencias Marinas, Universidad Autónoma de Baja California, Apartado Postal 453, 22830, Ensenada, Baja California, México
³Research Center for Inland Seas. Kobe University, Rokkodai, Kobe 657-8501, Japan

*Corresponding Author

Email: laguilar@uabc.mx

ABSTRACT

Sargassum filicinum Harvey, a brown alga (Phaeophyceae) native to Northeastern Asia, has been recently reported from the coast of Southern California (USA). Here we report the occurrence and range extension of this introduced species, as we found the alga at La Jolla and Rancho Packard in Todos Santos Bay, Baja California, Mexico. The first collections of S. filicinum correspond to several immature plants, found on September 8, 2005, drifting in the intertidal zone at La Jolla. Later on November 9, 2006, we found a well-established population in Rancho Packard in the middle intertidal zone to 2 m depth. Since S. filicinum is an annual monoecious species with air bladders, the risk there is a high risk of spreading rapidly along the Pacific, as in the case for S. muticum. The population in Rancho Packard extends 500 m along the coast, consisting mainly of young plants with an average length of 30 cm and a density of 5 thallus/m2. This is the first record of this invasive species for the Mexican Pacific coast, and it represents the southern limit along the Pacific coast of North America. This finding suggests that this invasive species has successfully colonized the Pacific coast of North America and its distributional range is still expanding.

Key words: introduced species, invasive species, molecular identification, Pacific Mexico, Sargassum filicinum