Temporal variation of Skeletonema community composition from a long-term time series in Narragansett Bay identified using high-throughput DNA sequencing
Morphologically cryptic plankton species are abundant in marine waters but are difficult or impossible to identify using microscopy, making it challenging to document biodiversity and understand how species composition influences ecosystem function. High-throughput DNA sequencing of field samples has revealed enormous hidden diversity but quantifying species abundance using this method is problematic. Using a combination of microscopy and high-throughput sequencing of field and mock communities, Canesi and Rynearson identified seasonal patterns in morphologically cryptic species in the ecologically important diatom genus Skeletonema from a long-term time series. The seasonal patterns suggest that Skeletonema species are likely adapted to different environments, raising the possibility that species composition of this important bloom-forming genus may shift as water temperatures increase due to anthropogenic influences.