Northwest Diatoms, Volume 5: Encyonopsis
Bahls LL. 2013. Northwest Diatoms, Volume 5: Encyonopsis. Helena, MT
Thirty-one species of Encyonopsis from western North America are documented with photographs of specimens on slides in the Montana Diatom Collection (MDC). Seventeen of these species are described as new: Encyonopsis aequaliformis, E. albertana, E. anacondae, E. bobmarshallensis, E. czarneckii, E. dakotae, E. descriptiformis, E. hustedtii, E. kutenaiorum, E. lacusalpini, E. lacuscaerulei, E. lacusglacialis, E. medicinalis, E. montana, E. stafsholtii, E. treinishii, and E. weilandii. Also, one infraspecific taxon is elevated to species: Cymbella microcephala fo. robusta to Encyonopsis robusta. The study area encompasses mountainous and forested regions of Alberta, Idaho, Montana, Oregon, South Dakota, and Washington. Here species of Encyonopsis are found mostly in small headwater lakes, ponds, springs, seeps and streams. These waters are typically unpolluted, cold and weakly acidic to moderately alkaline, with high dissolved oxygen and low to moderate concentrations of nutrients and dissolved solids. Northwest Montana, west of the Continental Divide, is a biodiversity hotspot for Encyonopsis species. The potential is substantial for finding new species in other diatom genera among samples in the MDC and in other collections from remote regions of North America.