Rhogostoma
Rhogostoma
Rhogostoma spec. – Kloosterhaar and R. minus (photomicrograph: Yana Eglit)

Genus Rhogostoma Belar, 1921

Belar (1921) described two Rhogostoma species that differed from freshwater Lecythium in four respects:

  1. having a narrow crack-like, not a large round, aperture;
  2. being filose not reticulose;
  3. being several times smaller (R. minus 10-12 µm, R. schuessleri 15 µm);
  4. thecae having bilateral not radial symmetry.
from Dumack et al., 2017
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