Morphological observations on Pseudoeunotia linearis Carter (Bacillariophyta) and its transfer to the genus Eunotia

摘要

During a survey of the moss-inhabiting diatom flora of Gough Island (Tristan da Cunha archipelago, southern Atlantic Ocean), a large population of Pseudoeunotia linearis Carter has been observed. A detailed morphological analysis has been made using light and scanning electron microscopy to reveal its ultrastructure. The results show a eunotioid structure with short raphe branches, uniseriate striae with irregularly placed rimmed areolae, and marginal linking spines surrounding the valve face. Based on these features, the position of P. linearis within the genus Pseudoeunotia cannot be confirmed and a transfer to the genus Eunotia is therefore suggested.