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Lara Panayotoff Kentucky Division of Water

Ensuring quality diatom taxonomic identifications and developing diatom-based metrics for diagnosing nutrient impairment in Kentucky. Lara Panayotoff Kentucky Division of Water. Does it matter?. Genus Level resolution? Isn’t internal consistency enough?

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Lara Panayotoff Kentucky Division of Water

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  1. Ensuring quality diatom taxonomic identifications and developing diatom-based metrics for diagnosing nutrient impairment in Kentucky Lara Panayotoff Kentucky Division of Water

  2. Does it matter? • Genus Level resolution? • Isn’t internal consistency enough? • All this “splitting” is messing with my head! Why are taxonomists doing this to me? • My historical dataset is worth what now? • It’s doable, it’s getting easier • Regional and national comparability provides more complete context for local information • It expands the usefulness of our data beyond our borders

  3. Diatoms of the US: Kickin’ it old school • despite 800+ taxa represented, quite incomplete • line drawings often hard to interpret • many taxa represented by just one drawing

  4. Sprechensie Deutsch?

  5. Regional floras, monographs, and journal articles

  6. National Programs – comparability, consistency? • North American Diatom Ecological Database (NADED) - ANSP • Image databases • Program-focused taxonomy workshops • Slides deposited in publically accessible herbarium • Numerous publications of new taxa or treatment of problem groups NAWQA

  7. New Web Resource for Diatom Identification Diatoms of the United States • formal editorial review • high quality information • dynamic • relative few species at this time (207) but expanding quickly Spaulding, S.A., Lubinski, D.J. and Potapova, M. (2010). Diatoms of the United States. http://westerndiatoms.colorado.edu Accessed on 07 November, 2011.

  8. Diatoms of the US: way informative species pages • many images representing size range • original species description and images • comparison with similar taxa • autecological information • species occurrence maps from EMAP

  9. KDOW’s 2008 Diatom taxonomy update project • reviewed taxa list, identification notes, and slides • nomenclature changes (e.g., genus transfers) • newly clarified concepts • taxa likely to be present but not reported • possible misidentifications • compare with NADED list and taxonomic concepts • some issues: • many cases of simple nomenclature differences • Achnanthidium deflexum • Gomphonema angustatum • “Achnanthes lanceolata” complex • Nitzschia, many groups • small Navicula • many unreported taxa

  10. KDOW’s 2008 Diatom taxonomy update project • original list 678 names - 319 taxon names added • 193 names “deactived” – historical data left unchanged but these names no longer accepted for new analyses • added new fields to taxa table: • reference description citation • reference figures citation • Authority • is_active • combine_to_name • NADED_ID • 87 names added since – currently 841 active names • 73 do not have NADED IDs: 42 legit names, 31 “unknowns”

  11. Diatom Digital Image Library • Spot Insight 4MP digital camera • SPOT software associates notes, measurements, scale bars with images – can burn to image or not • standardized filenames hold the taxon code and the sample ID; stamped onto image

  12. Diatom Digital Image Library • over 1000 images representing hundreds of taxa, filed in genus folders • hope to create database for easier searching and viewing; using Windows search for now • database also will help track verification status and notes

  13. 2011 Diatom QA project • FY09 106 supplemental grant funds (in part) • MOA with Academy of Natural Sciences, Diatom Herbarium Curator Marina Potapova • Focus on 2008-10 nutrient studies in Pennyroyal and Mountains regions

  14. 2011 Diatom QA project • Objectives: • Verification of 300+ voucher images representing 150 taxa – all “common” or “frequent” taxa (>1% in any sample) • Verification or guidance for 2 taxonomic problem areas • “Achnanthidium deflexum complex” • “Gomphonema angustatum complex” • Recommendations for several “unknowns” or uncertain identifications

  15. 2011 Diatom QA project: Image Verification Differences in splitting Cocconeis placentula var. lineata vs. euglypta Navicula minima vs. Sellaphora seminulum Differences in nomenclature Achanthes nollii is Achnanthidium latecephalum Gomphonema pumilum is G. kobayasii Downright wrong Navicula absoluta, really N. ruttneri var. capitata Diplonies boldtiana, really D. puella Nitzschia supralitorea, really N. liebetruthii Voucher image verifications: 305 of 368 confirmed ok

  16. 2011 Diatom QA project: Image Verification Voucher image verifications: 305 of 368 confirmed ok “Achnanthes pinnata” “Chamaepinnularia evanida” “Encyonema hebridicum” undescribed Platessa Navicula sp. 5 ANS NEW JERSEY KCP Encyonema sp. 1 MONTANA HAMSHER

  17. 2011 Diatom QA project : Achnanthidium A. sp. 1 KYDOW LAP A. deflexum A. rivulare • gracillumum • latecephalum • (“A. nollii”) A. druartii ( A. sp. 3 KDOW LAP) (Achnanthidium sp. 3 cf. alteragracillima KYDOW LAP)

  18. 2011 Diatom QA project : Achnanthidium Spaulding, S.A., Lubinski, D.J. and Potapova, M. (2010). Diatoms of the United States. http://westerndiatoms.colorado.edu Accessed on 07 November, 2011.

  19. 2011 Diatom QA project: Achnanthidium undescribed Achnanthidium Achnanthidium sp. 1 KYDOW LAP. Photo by Marina Potapova Scale bars = 1 micron

  20. 2011 Diatom QA project: Gomphonema “Gomphonema angustatum complex” G. drutiligense G. cymbelliclinum G. innocens G. micropus G. sp. 8 cf. sarcophagus KYDOW LAP

  21. 2011 Diatom QA project: Unknowns 6 unknowns judged to be “probably undescribed species” 10µm Planothidium sp. 1 KYDOW LAP Sellaphora sp. 1 KYDOW LAP Sellaphora sp. 2 KYDOW LAP Navicula sp. 1 KYDOW LAP Navicula sp. 2 KYDOW LAP Nitzschia sp. 2 KYDOW LAP

  22. 2011 Diatom QA project: Unknowns holotype Hohn, M.H. 1961. The Relationship Between Species Diversity and Population Density in Diatom Populations from Silver Springs, Florida. Trans. Amer. Micro. Soc. 80(2):140-165. Navicula dibola Hohn Photos by Marina Potapova

  23. 2011 Diatom QA project: QC Analyses QC analyses on 19 slides: 1000 valve count, separate “strips” Discrepancies- many of the same issues from voucher images, plus several more • Achnanthidium eutrophilum / A. minutissimum • Cymbella turgidula / C. subturgidula / C. tropica • Encyonema silesiacum / E. neogracile • Remeria sinuata / uniseriata • Navicula absoluta / N. ruttneri var. capitata Percent Similarity: Initial: range from 49 – 89% After resolving identification discrepancies: 76-91% where: ai = percentage of species i i count A bi = percentage of species i in count B

  24. 2011 Diatom QA project outcomes • verified images can be used as reference in the future • improved confidence in comparability • many unknowns confirmed to still be unknown • problems to look out for • contributed to understanding of rarely reported taxa, slides accessioned at ANSP accessible to researchers • better idea of range of recount % similarity to expect • QC recounts, voucher verifications, and special problems work gave different and complementary information

  25. So where does that get us? • % Eutrophic diatom individuals or taxa • Trophic Index • % Hi TP/TN and Low TP/TN indicating individuals or taxa • Oxygen Tolerance Index • Saprobity Index http://pubs.usgs.gov/ds/ds329/

  26. Thanks! Questions?

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