1	"Costa absent"	Hollia
1	"Costa present"	2
2	"Midlaminal cells with a single branched papilla; stems with very sparse rhizoids; male and female plants similarly sized"	Sclerodontium
2	"Midlaminal cells smooth; stems tomentose; male plants conspicuously dwarfed and embedded in tomentum of sterile or female plants"	3
3	"Peristome usually remaining intact, asymetrically bifid in apical half; capsules usually curved, sometimes straight"	Dicranoloma
3	"Peristome fragile and usually with pieces broken off, entire or irregularly fenestrate or split to base; capsules straight"	Holomitrium