Aloina is a genus of mosses with three species in British Columbia. Although they are very tiny (and hard to photograph!), they are a very distinct group of mosses characterized by individual plants having a few tiny, thick, tongue-shaped, succulent leaves.
The upper surface of the leaves are covered in numerous filaments consisting of green photosynthetic tissue. These filaments greatly increase the photosynthetic surface area of these tiny leaves. In addition, the edges of the leaves fold over the upper surface of the leaves which likely protects the filaments to a certain extent from water loss and function a little bit like a miniature greenhouse. This is important in that these species occur on silty soils in dry, open grasslands like those found around Kamloops.
A cross-section through the leaf of Aloina showing the photosynthetic filaments that are packed on the upper surface of the leaf.
A cross-section through the leaf of A. brevirostris. Note how the edges of the leaves fold over the top of the photosynthetic filaments.
Two of the species, A. brevirostris (shown in the above photo) and A. rigida, are difficult to distinguish from one another but A. bifrons is distinguished by having leaves with long clear hairpoints. Although tiny, the thick fleshy leaves can be recognized in the field with a 10X hand lens.
These are remarkable little plants that show some of the innovations that organisms make to adapt to the environment in which they live.