Homworts + mosses

The mosses are the largest of the three classes in the plant phylum Bryophyta. They have been divided into three subclasses the true mosses (Bryideae), the peat mosses (Sphagnideae), and the granite mosses (An-dreaeideae). The familiar small, green, and leafy moss plant is known as the gametophyte. This haploid multicellular phase is dominant in the moss life cycle. The mosses are the most broadly distributed of the three classes of bryophytes (which also includes liverworts and homworts). There are more than 15,000 species of mosses worldwide. 

Bryophytes, constituents of (constituents of mosses). Bryophytes produce numerous secondary metabolites that have not yet been found in other plants. They are mostly phenolic compounds and terpenes, there are considerable differences between the individual classes of mosses. Homworts (Anthocerotae) are characterized by the presence of lignans, liverworts (Hepaticae) principally by terpenes, especially sesqulterpenes that are often enantiomers of the compounds found in higher plants and bibenzyl derivatives. Mosses (Musci) contain biflavonoids (see flavonoids), sphagnorubins (peat mosses) and cou-marin derivatives. Alkaloids are rare and have as yet only been found in liverworts. 

Some mosses do, however, synthesize flavone C- and O-glycosides, biflavonols, dihydroflavones, etc., (54) from p-coumaroyl-CoA 5 or caffeoyl-CoA 48 esters (and malonyl-CoA 49). Thus, these organisms have evolved a partially developed phenylpropanoid pathway to afford metabolites presumably helping offset the effects of UV-irradiation, or providing cell wall polymers with properties "akin" to lignin. Related flavonoids are also found in the liverworts and homworts (54),... 

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