Home / Diatoms / Pennate / Biraphes / Unicells / Asymmetric / Rhoicosphenia
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Name derivation:
Classification:
Rhoicosphenia Grunow 1860; 11 of 22 species descriptions are currently accepted taxonomically (Guiry and Guiry 2014). Order Cymbellales; Family Rhoicosphenia
Morphology:
Biraphe unicellular diatom asymmetric in girdle view, curved. The convex valve has a raphe on its central axis; the concave valve has a short raphe ‘branch’ near the ‘footpole’. (Spaulding and Edlund 2008). Cells produce short mucilaginous stalks that are attached to a substrate.
Similar genera:
Habitat:
Common in both freshwater and marine ecosystems and has been found on nearly every continent (Thomas and Kociolek 2015). Freshwater streams and wave-washed littoral benthos of lakes. Widely found in Antarctica in near shore ecosystems is Heteropolar Rhoicosphenia (Ligowski et al. 2014)
References:
Grunow, A. 1860. Über neue oder ungenügend gekannte Algen. Erste Folge, Diatomeen, Familie Naviculaceen. Verhandlungen der Kaiserlich-Königlichen Zoologisch-Botanischen Gesellschaft in Wein 10: 503-582, pls III-VII. Guiry, M.D. and G.M. Guiry 2013. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 22 May 2013. Spaulding, S., and M. Edlund 2008. Rhoicosphenia. In Diatoms of the United States. Retrieved June 13, 2014, from http://westerndiatoms.colorado.edu/taxa/genus/Rhoicosphenia (online) Thomas, E., Kociolek P. 2015. Taxonomy of three new Rhoicosphenia (Bacillariophyta) species from California, USA. 204 (1): 001–021. Ligowski R., Handal A., Wulff A., Jordan R. 2014. Rhoicosphenia michali: a new species of marine diatom (Bacillariophyta) from King George Island, Antarctica. 191 (1): 141–153.