Finger-leaf liverwort is a very unusual looking liverwort. Most liverworts either consist of a thallus, a flat green layer of tissue that lacks stems and leaves, or leafy liverworts, in which the single leaves, usually entire or with lobed margins, are usually arranged in two rows along the stem. The leaves are either entire or lobed.

Finger-leaf liverwort (Blepharostoma trichophyllum) is different in that the leaves are arranged on all sides of the stem and each leaf is divided to the base into three linear segments that are only a single-cell wide.

This is a very common species on the shaded underside of well-decayed logs where they remain moist throughout the growing season. They appear like a green fuzz that may be mistaken for algae but with a handlens (or very good eyesight) the narrow stems with linear leaves can be easily viewed. It often grows with other small liverworts in shaded microsites where it does not have to compete with larger mosses and liverworts.

There is a second species that belongs to the genus Blepharostoma that is very rare and is known from a few locations ranging from southwestern BC south to California. It differs in that the linear leaves are subdivided into even finer segments (Blepharostoma arachnoideum).