Aulacoseira principissa sp. nov., a new ‘centric’ diatom species from the sub-Antarctic region

• Published in: Phytotaxa
• Main Author: DE VIJVER, BART VAN
• Format: Article in Journal/Newspaper
• Language: English
• Published: Phytotaxa 2012
• Subjects: aquatic habitat; morphology; sub-Antarctic Region; ultrastructure; Algae; Antarctic; Indian; Antarc*
• Online Access: http://www.mapress.com/j/pt/article/view/phytotaxa.52.1.5; https://doi.org/10.11646/phytotaxa.52.1.5

A new centric diatom, Aulacoseira principissa sp. nov., is described from the sub-Antarctic region. The morphology of the species is illustrated using detailed light and scanning electron microscopy observations. Its main discriminating features include the presence of typical bifurcating spines, a single rimoportula, a typical valve heterovalvy with spineless separation valves and a variable striation pattern on the discus. The new species is compared to related species belonging to the complex of Aulacoseira distans. Aulacoseira principissa has a broad geographical distribution ranging from the sub-Antarctic islands in the southern Indian Ocean to South Georgia in the southern Atlantic Ocean. It is commonly found in slightly acidic, oligotrophic pools with low specific conductance values.