Moss Plants and More: Mosses Growing on Leaves

I have seen a ton of epiphyllous bryophytes while in Costa Rica. These are mosses or liverworts (I don't think that there are any epiphyllous hornworts) that grow on (epi-) the leaves (-phyllous) of other plants. Here are a few of the examples that I have seen.

This is a moss growing on the leaf of a bromeliad. It is in the Bromeliaceae, the same plant family as pineapples. The moss was growing very tightly appressed to the leaf surface. I was able to get some of it off after taking this picture, but it took some scraping and a bit of pulling. (photo taken at Las Cruces)

This leaf is covered by epiphyllous liverworts. Many of the older leaves on the forest plants in Costa Rica are covered by mosses, liverworts, and fungi (those are the white patches on the leaf below). Once these older leaves are overtaken by bryophytes they are pretty useless to the plant. The bryophytes intercept all of the light that the leaf would normally receive and thus the leaf carries out little to no photosynthesis. (photo taken at Las Cruces)