How to recognize Physcomitrium collenchymatum: The leaves on this little plant are up to 2 mm long and often toothed near the tip, and have a single midvein. The capsule stem is only 2-3 mm long, and the ovoid to hemispheric capsules 0.5 -1.2 mm become pear-shaped or bell-shaped when old. It differs from its big brother Physcomitrium pyriforme by the toothed leaves, and much shorter seta or capsule stem, and also by being a smaller plant.
Where to find Physcomitrium collenchymatum: It is found in wet disturbed places; the capsules mature late fall to spring. In Ohio, this moss is known from an early-stage wet prairie restoration at Batelle Darby Metro Park in Franklin County, where it was collected only once, in early November, 2011. It is an extremely rare species, endemic to North America (see distribution map HERE).