Fissidens obtusifolius
“blunt-leaved pocket moss”
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Fissidens obtusifolius. Greenville Falls State Nature Preserve. Miami County OH. October 11, 2014.
How to recognize blunt-leaved pocket moss: Fissidens obtusifolius is a typical Fissidens; the plants are flat with leaves in 4-12 pairs, but the rounded leaf tips are distinctive. The leaves are usually over 1 mm in length at the stem tip. The leaf tips are broadly rounded and usually obtuse on an oblong leaf. There are no teeth on the edges of the leaves and sometimes a clear border on the lower part of the leaf. Under a microscope the single costa extends to 3-12 cells of the leaf tip.
Where to find blunt-leaved pocket moss: Fissidens obtusifolius is found on wet sandstone or limestone, either on the rock or thin soil. It is often very near the water. It likes calcareous areas.