The Montana Diatom Collection

Helena, MT, United States

The Montana Diatom Collection

Helena, MT, United States
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Five new species of Stauroneis are described from the northern Rocky Mountains-S. clarkii, S. lewisii, S. sacajaweae, S. spauldingiae, and S. thompsonii-for a total of 21 new Stauroneis species from the region. All of the new species are local or regional endemics. Water bodies supporting populations of Stauroneis tend to be small, remote, isolated, circumneutral, oligo- or dystrophic, and with low levels of electrolytes. These findings have implications for estimating diatom biodiversity and for conserving endemic diatom species and their habitats. © 2012 Magnolia Press.


Staurophora brantii is described from streams of the northwestern Great Plains in the western United States. The new species is placed in Staurophora by virtue of its plastid type, valve structure, and ecology. It is distinguished from similar species by its size, valve shape, end shape, striae count, and habitat. Staurophora brantii sp. nov. lives in alkaline freshwater streams with soft, muddy bottoms and elevated concentrations of electrolytes, particularly sodium and sulfate. Stauroneis tackei, an associate of Staurophora brantii on the Great Plains, is transferred to Staurophora. © 2012 Magnolia Press.


The new genus Kurtkrammeria is erected to include 13 species assigned to Encyonopsis that have (1) slit-like or crescent-shaped areolae aligned lengthwise along the apical axis, (2) striae convergent at the apices, and (3) internal proximal raphe ends hooked strongly towards the dorsal side of the valve. Some species of Kurtkrammeria also have dorsal stigmata, apical pore fields and internal anastomosing costae at both poles, and lateral papilla-like projections from intercostae into internal areola openings. Species of Kurtkrammeria are reported infrequently from fossil deposits and from recent diatom assemblages. Kurtkrammeria is a genus of remote and undeveloped regions from the Arctic to the Tropics, in both the Old World and New World. Most species are local or regional endemics and only four species – K. aequalis, K. neoamphioxys, K. recta, and K. subspicula – appear to be widely distributed. Kurtkrammeria species consistently occur in oligotrophic or dystrophic waters with very low specific conductance and circumneutral pH. An extant population of the very rare Kurtkrammeria stodderi is described from Montana, USA. Living cells of K. stodderi were observed to be motile and to have plastids similar to those of Encyonema species. Examination under SEM reveals that K. stodderi also has apical pore fields at both poles. © 2014 J. Cramer in Gebr. Borntraeger Verlagsbuchhandlung, Stuttgart, Germany.


Bahls L.,The Montana Diatom Collection | Potapova M.,Drexel University
Phytotaxa | Year: 2015

Two species of Navicula—N. volcanica and N. subwalkeri—are described as new based on LM and SEM observations and a comparison with similar species. Modern distributions of the new species are restricted to two adjacent headwater streams along the crest of the Cascade Mountains in western Oregon, USA. Both species are established as extant based on observations of cells with intact chloroplasts. Navicula volcanica has uniquely structured areolae with small external openings fused into narrow and occasionally interrupted transapical slits, while in most other Navicula species both the external and internal openings are separate and apically elongated. When observed under LM, N. volcanica resembles N. ludloviana, from which it can be distinguished by its rhombic valve shape, unprotracted apices, and larger size. We present here the first SEM images of N. ludloviana, showing that unlike N. volcanica, this species has ultrastructure typical for Navicula sensu stricto. We also present new distribution records for N. ludloviana and populations that eclipse published ranges of valve size and shape for this species. Navicula subwalkeri is similar to N. walkeri in that both species possess an internal axial plate that partially covers the striae. It is distinguished from N. walkeri by its narrower valves and axial plate, protracted apices, smaller central area, curved striae, and higher density of areolae. Navicula subwalkeri and N. walkeri are sympatric species, although N. walkeri is much more widely distributed. Additional distribution records are provided for N. walkeri, including the first record from the State of Washington. © 2015 Magnolia Press.


Winter D.,Rhithron Associates Inc | Bahls L.,The Montana Diatom Collection
Phytotaxa | Year: 2013

A new species of Encyonema is described from the benthos of small mountain streams and rivers in western Montana and northern Wyoming. Previously this species had been identified incorrectly as E. hebridicum Grunow ex Cleve and Cymbella affinis Kützing or assigned the provisional name Encyonema sp. 1 MONTANA HAMSHER ANSP. Here we formally recognize this taxon as a new species, Encyonema hamsherae. © 2013 Magnolia Press.


Bahls L.,The Montana Diatom Collection
Phytotaxa | Year: 2013

Twelve new species of diatoms are described from material collected in Colorado, Montana, Oregon, Washington, and Wyoming, USA, and in Alberta and British Columbia, Canada. The new species are Cavinula davisiae, Craticula johnstoniae, Craticula sardiniana, Cymatopleura internationale, Cymbella cosleyi, Cymbopleura edlundii, Gomphonema johnsonii, Navicula supleeorum, Navicula trilatera, Neidium bobmarshallensis, Stauroneis boyntoniae, and Staurophora columbiana. Two varieties are elevated to species: Neidium fogedii (replaced synonym: N. kozlowii var. densestriata) and Neidium undulatum (replaced synonym: N. kozlowii var. undulata). Two species are transferred to new genera: Cymbella rainierensis to Cymbopleura and Navicula soodensis to Staurophora. An Alberta population of Neidium inconstans representing significant morphological variation and range extension for this species is also presented. Water quality preferences of these taxa run the gamut from ultraoligotrophic to hypereutrophic and fresh water to hypersaline. Thirteen of these taxa are either local or Northwest regional endemics. Four of these taxa are members of the Holarctic diatom flora or they are cosmopolitan. © 2013 Magnolia Press.

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