Meesia triquetra, the three-ranked hump-moss,[1] is a moss that occurs all around the northern hemisphere in higher latitudes.

Its leaves are decurrent, squarrose (spreading) when moist, triangular to ovate to lanceolate, somewhat crispate (contorted), 2–3½ mm long, and tristichous (in three obvious ranks).

The costa is relatively narrow (less than 1/5 the width of the leaf base), subpercurrent to percurrent, gradually tapering at distal end.

[2][3][4][5] Meersia triquetra is easily recognized by its distinct three-ranked leaf arrangement and for being dioicous.

Fire return intervals in conifer bogs, a somewhat similar mire-type habitat, are estimated to be about once every 150–200 years.

California Native Plant Society List 4.2 NatureServe California State Rank: S2.2; Global Rank: G5 Fens are delicate habitats susceptible to impacts from livestock grazing, hydrologic alteration, construction and continued use of roads, and peat mining.