First record of benthic diatoms (Bacillariophyceae and Fragilariophyceae) from Isla Guadalupe, Baja California, Mexico

• Published in: Revista mexicana de biodiversidad 2015-06, Vol.86 (2), p.281-292
• Main Authors: López-Fuerte, Francisco Omar, Siqueiros-Beltrones, David A., Yabur, Ricardo
• Format: Article
• Language: English
• Subjects: Bacillariophyceae; Bacillariophyta; Biodiversity Conservation; Eastern Pacific; Epifitas; Epilithic; Epilíticas; Epiphytic; Epizoic; Epizoicas; Fragilariophyceae; Insular; Marine; Pacífico oriental
• ISSN: 1870-3453; 2007-8706; 2007-8706
• DOI: 10.1016/j.rmb.2015.04.016

Guadalupe Island represents a unique ecosystem. Its volcanic origin and remoteness from the Baja California peninsula have allowed for the successful establishment of its distinctive flora and fauna. However, the difficulty in accessing the island has precluded the study of its biotic communities, mainly the marine ones. Consequently, no studies on benthic or planktonic diatoms have been hitherto published. Thus, the first records of marine benthic diatom species (epiphytic, epilithic, epizoic) from Guadalupe Island in the NW Mexican Pacific are here provided. One hundred and nineteen diatom taxa belonging to the Bacillariophyceae and Fragilariophyceae were identified, including species and varieties. The former with 87 taxa was the most diverse. Thirteen taxa are new records for Mexico; photographic images of these are provided. Because this is the first study for the benthic diatoms of Isla Guadalupe, a particular bio-geographical affinity is not proposed. However, the best represented genus was Mastogloia which has tropical affinity, and Cocconeis thalassiana was also identified, a new species recently recorded for the Mexican Caribbean. Isla Guadalupe es única como ecosistema; su origen volcánico y lejanía de la península de Baja California han permitido que el desarrollo evolutivo de sus distintivas flora y fauna haya sido exitoso. La dificultad para acceder a la isla es causa de que algunas comunidades, principalmente marinas, no hayan sido estudiadas aún. Consecuentemente, a la fecha no existía algún estudio publicado sobre diatomeas. Así, se presenta el primer registro de diatomeas bentónicas (epilíticas, epifitas y epizoicas) de isla Guadalupe en el noroeste de México. Se identificaron 119 taxa (incluyendo especies y variedades) de diatomeas pertenecientes a las clases Bacillariophyceae y Fragilariophyceae. Las primeras fueron más diversas con 87 taxa. Del total, 13 taxa son nuevos registros para México y se proveen imágenes fotográficas de ellos. Dado que se trata apenas del primer estudio para la flora de diatomeas bentónicas de isla Guadalupe, no se propone una afinidad biogeográfica. Sin embargo, uno de los géneros con mayor número de especies es de afinidad tropical, i.e., Mastogloia y se identificó Cocconeis thalassiana, una especie nueva recientemente registrada para el Caribe mexicano.