The shell or the kernel: biodiversity estimates of benthic foraminifera

• Published in: Journal of Eukaryotic Microbiology
• Main Authors: HABURA, ANDREA, HANES, STEVEN D., ALEXANDER, STEPHEN P., BOWSER, SAMUEL S.
• Format: Article in Journal/Newspaper
• Language: English
• Published: Wiley 2005
• Subjects: Antarctic; McMurdo Sound; Antarc*; Antarctica
• Online Access: http://dx.doi.org/10.1111/j.1550-7408.2005.05202003_1_31.x; https://api.wiley.com/onlinelibrary/tdm/v1/articles/10.1111%2Fj.1550-7408.2005.05202003_1_31.x; https://onlinelibrary.wiley.com/doi/pdf/10.1111/j.1550-7408.2005.05202003_1_31.x

Estimates of protist biodiversity and distribution have until recently relied on the morphological identification of individual cells. The advent of environmental‐DNA‐based surveys of these protist communities has broadened our understanding of species richness and diversity. A “total‐evidence biodiversity” approach gives two benefits. First, it allows “back‐comparison” to previous studies of ecosystems, permitting estimates of the amount of cryptic diversity in different sampling regimes (and by extension, the fossil record). Second, it will provide the best possible estimate of the total species richness of current study sites. Here, we use a well‐studied benthic protist community, the foraminiferal assemblage of McMurdo Sound, Antarctica, to determine the effective parameters of both detection methods. We find that molecular‐based techniques detect well‐characterized calcareous species at depths too great to allow calcification, suggesting that these forms may be able to survive without their distinctive tests. “Fragile” taxa also appear to be better represented in molecular surveys than in morphological ones. The strengths of a combined morphological–molecular approach are demonstrated by an assessment of the distribution of two species in the genus Notodendrodes; morphological detection excels in the identification of distinctive, patchily distributed adults, whereas molecular detection with taxon‐specific probes enabled identification in less favorable sampling conditions. Such a “broad‐plus‐deep” approach appears to maximize detection efficiency in this Antarctic setting. Work supported by NSF OPP0003639.