The genus Pseudo-nitzschia (Bacillariophyceae) in Manzanillo and Santiago Bays, Colima, Mexico

Abstract

Abstract In this study, morphological characters were used to describe the diversity and seasonal variability of the genus Pseudo-nitzschia in a coastal region of the Mexican tropical Pacific Ocean. Eleven species were characterized from cultures and field material: Pseudo-nitzschia americana, Pseudo-nitzschia australis, Pseudo-nitzschia brasiliana, Pseudo-nitzschia delicatissima, Pseudo-nitzschia cf. delicatissima, Pseudo-nitzschia dolorosa, Pseudo-nitzschia cf. fryxelliana, Pseudo-nitzschia micropora, Pseudo-nitzschia multistriata, Pseudo-nitzschia pungens var. aveirensis, and Pseudo-nitzschia subfraudulenta. The maximum diversity and abundance occurred in spring, in parallel with a local upwelling, whereas fewer species were detected in autumn. Among those analyzed, the only species to be detected throughout the year at several stations was P. cf. fryxelliana, whereas the rarest species in the study area was P. americana, which was detected only in the spring.