How to recognize Platdictya confervoides: This moss grows as a mass of tiny branched green threads on calcareous rocks in moist shady places, especially near streams. The leaves are only 0.15 to 0.3 mm long and are erect and appressed when dry, and somewhat spreading when moist. They are lanceolate or ovate-lanceolate in shape without a costa or with a minimal indication of one. Under the compound microscope there are 2-3 rows of subquadrate alar cells with 2-10 cells extending up the margins. The rhizoids are smooth or lightly roughened. Platydictya jungermannioides differs by having papillose rhizoids, no midrib, and only one row of alar cells. These plants have male and female organs on a single plant so the ~1 mm capsules may be present on a short 6-8 mm seta.
Where to find Platdictya confervoides: Look for this moss on limey rocks near streams.