New and interesting species of the genus Muelleria (Bacillariophyta) from the Antarctic region and South Africa

Abstract

Van de Vijver B., Mataloni G., Stanish L. and Spaulding S.A. 2010. New and interesting species of the genus Muelleria (Bacillariophyta) from the Antarctic region and South Africa. Phycologia 49: 22–41. DOI: 10.2216/09-27.1

During a survey of the terrestrial diatom flora of some sub-Antarctic islands in the southern Indian and Atlantic Oceans and of the Antarctic continent, more than 15 taxa belonging to the genus Muelleria were observed. Nine of these taxa are described as new species using light and scanning electron microscopy. Comments are made on their systematic position and how they are distinguished from other species in the genus. Additionally, two previously unrecognized taxa within the genus were discovered in samples from South Africa. One of these, Muelleria taylorii Van de Vijver & Cocquyt sp. nov., is new to science; the other, Muelleria vandermerwei (Cholnoky) Van de Vijver & Cocquyt nov. comb., had been included in the genus Diploneis. The large number of new Muelleria taxa on the (sub)-Antarctic locations is not surprising. Species in Muelleria occur rarely in collections; in many habitats, it is unusual to find more than 1–2 valves in any slide preparation. As a result, records are scarce. The practice of “force-fitting” (shoehorning) specimens into descriptions from common taxonomic keys (and species drift) results in European species, such as M. gibbula and M. linearis, being applied to Antarctic forms in ecological studies. Finally, the typical terrestrial habitats of soils, mosses and ephemeral water bodies of most of these taxa have been poorly studied in the past.

ACKNOWLEDGMENTS

The authors wish to thank Prof. Dr Louis Beyens and Dr Niek Gremmen for the collection of samples on King George Island, Heard Island and the Prince Edward Islands. Sampling on Crozet and Kerguelen has been made possible thanks to the logistic and financial support of the French Polar Institute-Paul-Emile Victor in the framework of the terrestrial program 136 (Ir. Marc Lebouvier & Dr. Yves Frenot). Part of the study was financed by the FWO project G.0533.07. Mrs Myriam de Haan and Mr Marcel Verhaegen are thanked for their technical assistance with the SEM. Thank you to the USGS Fort Collins Science Center for support for S.A. Spaulding for this project. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the US government. Dr David M. Williams and two anonymous referees are thanked for their comments that greatly improved the manuscript.