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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.