C. grandiflora is a rather small liverwort which is found near watery places in alpine and subalpine habitats. The shoots are around 2 mm wide or less, erect, and arise from buried stolons and old stems. Plants have a dark coloration varying from green to dark brown or black. The leaves are round and devoid of teeth and are inserted transversely onto the stem. When dry, the leaves appear appressed to the stem. The capsules develop within oval perianths on the main stem.

C. grandiflora may be mistaken for Solenostoma but the latter species does not have stolons.

When dry, C. grandiflora may also resemble Jamesoniella colorata but the latter species more often has yellow to red leaves and has papillose leaf cells.