Description: Keeled diatoms refer to a broad, informal morphological group of taxa with raphes in a canal often raised on a keel. But what is a keel? And what is a raphe in a canal?? This webinar will cover important morphological structures used to identify keeled diatoms, many of which are relatively large and highly ornamented. A high-level overview of freshwater genera in the orders Bacillariales, Surirellales, and Rhopalodiales will include morphology and basic ecology. The most technical part of the webinar will be about the recent reclassification of Rhopalodia, Surirella, and related taxa proposed by Ruck and colleagues. Reading the following articles prior to or after the webinar is highly encouraged:

  • Ruck, E.C., Nakov, T., Alverson, A.J. and Theriot, E.C., 2016. Phylogeny, ecology, morphological evolution, and reclassification of the diatom orders Surirellales and Rhopalodiales. Molecular phylogenetics and evolution, 103: 155-171.
  • Jahn, R., Kusber, W.H. and Cocquyt, C., 2017. Differentiating Iconella from Surirella (Bacillariophyceae): typifying four Ehrenberg names and a preliminary checklist of the African taxa. PhytoKeys, 82: 73-112.

Target audience: This presentation will be directed at participants with a specialized interest in diatom systematics and taxonomy. It will be of particular interest to analysts and students working on rivers and lakes of North America. Others, however, from beginners to lay public are welcome to attend.