Bryophytes » Orthotrichaceae » Zygodon viridissimus Green Yoke-moss

Zygodon viridissimus Green Yoke-moss

(Dicks.) Brid.

A small, compact diocous, acrocarpous moss which grows as an epiphyte or on walls, masonary, and rock, usually in slightly shaded locations, forming mounds or cushions with neat starry-looking leaves that become twitsed and appressed to stems when dry. To separate it with confidence from other Zygodon species it is necessary to examine the leaves microscopically and check the structure of the gemmae, which are bullet-shaped with a lontitudinal septum as well as transverse septa (see photo). It rarely produces sporophyte capsules, which is also useful to know. It is widespread and common in southern Britain and more scattered in the north. It is common in Wales and found throughout West Glamorgan, particularly in the lowlands, but in upland conifer plantations it is much less common than Zygodon conoideus, which produces abundant sporophyte capsules.

Zygodon viridissimus - © Charles Hipkin
Zygodon viridissimus - © Charles Hipkin

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