Ophioglossum pendulum is an interesting, pretty fern. It “infests” the root masses of some large-growing aspleniums, platycerium, and other epiphytes. It can be grown readily without a host.
The photo above shows the variation between a form with straight, narrow fronds, a broad type, and the most common, easiest form. Other variations are becoming available, as this species volunteers in collections
Above, the straight, narrow type.
Below is the broad form, easily the most decorative.