Identification notes

It is usually the bright clusters of whitish-green gemmae which form on the apex of attenuated shoots which attract attention to this plant. Like O.sphagni, it has transversely inserted orbicular imbricate leaves, tiny underleaves, and flagellae (although these are generally less common), but tends to grow on substrates other than Sphagnum (but it can – see the images). It also lacks the marginal band of think-walled cells seen in O.sphagni and under the microscope it has huge trigones. It appears more branched than O.sphagni because the branches emerge from the side of the shoots as well as from underneath.

Calypogeia muelleriana has broadly rounded leaves and gemmae on attenuated stems but the leaves tend to be more elongated, are arranged in an incubous manner, and have large underleaves.

It tends to grow in moist acid habitats such as peat, decaying logs, humus on boulders, leaf litter under heather and damp sandstone rocks. The abundant gemmae seem to work well and in suitable conditions it can form large patches.

Distribution in Great Britain and Ireland

Scattered localities in suitable habits including upland areas and the bogs and wet heaths of southern England.