With more than 12,700 species worldwide (Christenhusz & Byng 2016), mosses are the second most diverse plant group after the Angiosperms. The largest of the three bryophyte lineages, they are nonvascular plants that lack true roots and specialized conducting tissues and propogate by disseminating haploid spores. They are generally ony a few centemeters tall but often form extensive colonies on trees, fallen logs, rocks and exposed soil. Sphagnum species mosses, mostly abundant in boreal wetlands, account for a significant portion of Earth's total vegetative cover and organic matter. Moss gametophytes have small, scale-like, overlapping leaves and are typically mat-forming. Spores are produced in capsules born on the long narrow stalks of the sporophytes which grow on and are nourished by the gametophytes. To browse, select the desired family under "Mosses" in the menu on the left.

Iris fulva, Nacogdoches, Texas
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