About Pellia epiphylla (L.) Corda
This species, Pellia epiphylla (L.) Corda, has fairly large, irregularly branched thalli that grow to over 1 cm wide and several centimetres long. Thalli are green, sometimes with a red or purple tinge. They are relatively featureless, with an ill-defined midrib and no visible network of cells on the surface. The underside of the thallus bears many long rhizoids, and has no ventral scales. Pellia epiphylla is monoicous, meaning both male and female sex organs grow on the same thallus. The small male sex organs are scattered along the midrib, while female sex organs grow near the tip of the thallus and are surrounded by a flap. This species produces spherical, greenish-black capsules that grow on stalks called setae. These setae are pale green and can reach up to 5 cm long. For reproduction, fertilisation occurs when the thallus is wet. The male sex organs, antheridia, absorb moisture, burst open, and release sperm. The sperm swim toward the female sex organs, archegonia, to fertilise the ova. The fertilised ovum develops into a small sporophyte plant that stays attached to the larger gametophyte parent plant. The sporophyte forms a capsule holding spores, which are released when the capsule matures and splits. The released spores then germinate to grow new gametophytes.
