A new Eunotia species, E. charliereimeri, is described from Bear Meadows Bog near State College, Pennsylvania. Bear Meadows is an open, montane, nutrient-poor fen that is about 1.6 km long and 0.5 km wide with its open wetlands dominated by Sphagnum, sedges, swamp laurel, blueberry, sundews, Rhododendron spp., alder, Spiraea spp., and mountain holly. Eunotia charliereimeri has been collected intermittently from Bear Meadows over the last decade. Among the eunotioid diatoms, E. charliereimeri is characterized by its arcuate-lunate valve, prominent terminal raphe ends, and two rimoportulae per valve. Most importantly, it has amphoroid frustule symmetry, a character recently used to support the description of the new eunotioid genus Amphorotia Williams et Reid. However, E. charliereimeri does not share several other key features with Amphorotia including marginal spines or silica-rimmed external raphe fissures. A sister taxon, E. sarraceniae Gaiser et Johansen, described from South Carolina bays, shares the characteristic amphoroid symmetry and lunate shape, but E. sarraceniae is more finely striated, less arcuate, and has more rostrate ends than E. charliereimeri.

New taxon: Eunotia charliereimeri Edlund et Brant