Trinacria (diatom) on:
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''Trinacria'' is an extinct genus of diatoms present during the early Eocene, named for its 
triskelion
A triskelion or triskeles is an ancient motif consisting of a triple spiral exhibiting rotational symmetry.
The spiral design can be based on interlocking Archimedean spirals, or represent three bent human legs. It is found in artefacts o ...
shape.M.D. Guiry in Guiry, M.D. & Guiry, G.M. 2014. AlgaeBase. World-wide electronic publication, National University of Ireland, Galway. http://www.algaebase.org; searched on 21 December 2014.
References
† Prehistoric SAR supergroup genera Fossil algae {{Diatom-stub