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Showing posts from October, 2017

Diatom of the Month - October 2017: Lindavia (Pantocsekiella) comensis complex

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by Elizabeth Alexson*
Twice a year, in early spring and late summer, our lab boards the Environmental Protection Agency’s Lake Guardian research vessel to collect samples as a part of their Great Lakes National Program Office biological monitoring program. Our role is to monitor phytoplankton in all five of the Great Lakes. In addition to assessing modern phytoplankton, we collect cores for paleolimnological investigations to examine historical shifts in diatom indicators.
Figure 1. Photographs taken aboard R/V Lake Guardian: (A) rosette sampler collecting water samples at sunrise, (B) sunset on Lake Huron, (C) box corer collecting sediment cores for paleolimnological analysis.
In our paleolimnology and monitoring work, we’ve encountered an abundance of the small centric diatom Lindavia comensis (Grunow) T. Nakov et al., which forms a diverse complex with high morphological plasticity. A species complex is a group of related species that share many characteristics and can be difficult to…