Tetraphidaceae

Plants minute and budlike or merely small, forming dense turfs or scattered patches; protonema producing chlorophyllose, perpendicular protonematal flaps, which are persistent or disappear after the development of the gametophores. Stems erect, to 1.5 cm. Leaves ovate or lanceolate, erect, three-ranked and appressed or spreading, costate or ecostate, cells smooth, rounded-hexagonal or oblong-rhomboid, basal cells elongate. Sexual condition autoicous; archegonia and antheridia on short stems at the plant base. Seta straight or flexuose, smooth or papillose. Capsule exserted, single, cylindric, ovate or shortly oblong-cylindric; peristome of four, single, unsegmented, narrowly triangular, multicellular teeth; annulus absent. Calyptra mitrate, smooth or plicate, naked. Spores green to yellowish, 10–16 µm, spheric, smooth or finely papillose.

Distribution

Circumboreal, disjunct to the Southern Hemisphere.

Discussion

Genera 2, species 4 (2 genera, 4 species in the flora).

Selected References

None.

Lower Taxa

Tetraphis, Tetrodontium

Illustrations

	Family ⠉	Taxon	Illustrator ⠉
	Tetraphidaceae Tetraphidaceae	Tetraphis geniculata Tetraphis pellucida var. trachypoda	Patricia M. Eckel Patricia M. Eckel
	Tetraphidaceae	Tetrodontium brownianum var. brownianum	Patricia M. Eckel
	Tetraphidaceae	Tetrodontium repandum	Patricia M. Eckel

Key

1	Plants with conspicuous stems to 1.5 cm, forming dense turfs or scattered patches, leaves costate, protonematal flaps not persistent, stalked asexual structures often present.	Tetraphis
1	Plants minute, bud-like, stems less than 0.05 cm, leaves weakly costate in distal leaves or costa absent, protonematal flaps persistent and usually present, specialized asexual structures absent.	Tetrodontium