Comparing Morphological and Molecular Estimates of Species Diversity in the Freshwater Genus Synura (Stramenopiles): A Model for Understanding Diversity of Eukaryotic Microorganisms.

We performed a comparison of molecular and morphological diversity in a freshwater colonial genus Synura (Chrysophyceae, Stramenopiles), using the island of Newfoundland (Canada) as a case study. We examined the morphological species diversity in collections from 79 localities, and compared these findings to diversity based on molecular characters for 150 strains isolated from the same sites. Of 27 species or species-level lineages identified, only one third was recorded by both molecular and morphological techniques, showing both approaches are complementary in estimating species diversity within this genus.

Speciation in protists: Spatial and ecological divergence processes cause rapid species diversification in a freshwater chrysophyte.

Although eukaryotic microorganisms are extremely numerous, diverse and essential to global ecosystem functioning, they are largely understudied by evolutionary biologists compared to multicellular macroscopic organisms. In particular, very little is known about the speciation mechanisms which may give rise to the diversity of microscopic eukaryotes. It was postulated that the enormous population sizes and ubiquitous distribution of these organisms could lead to a lack of population differentiation and therefore very low speciation rates.

Exploring Cryptic Diversity and Distribution Patterns in the Mallomonas kalinae/rasilis Species Complex with a Description of a New Taxon-Mallomonas furtiva sp. nov.

A complex of closely related Mallomonas taxa belonging to the section Papillosae, M. kalinae Řezáčová and M. rasilis Dürrschmidt, has been studied in detail by molecular and morphometric methods.