Key to Hypopterygiaceae genera
Current node
- Stems usually simple, occasionally sparingly branched, not differentiated into stipe and rachis, usually quadrangular, sometimes terete; sporophytes projecting beneath plane of gametophyte
- Stems branched, differentiated into an unbranched basal stipe and a more distal branched rachis section, terete; sporophytes projecting above plane of gametophore