Oedipodiaceae W. P. Schimper
Authors: Howard A. Crum
Plants gregarious to loosely tufted, 5--10, rarely 20 mm high, light-green when moist, dark green when dry; protonema thallose, branched. Stems erect, simple or forked by innovation. Leaves small and remote toward stem base, larger and crowded in open rosettes above; rounded-obtuse at the apex; margins plane or somewhat undulate, entire except for long, flexuose cilia at basal margins of upper leaves; costa single, broad at leaf base, ending 6--10 cells below the apex; alar cells absent. Asexual reproduction by discoid brood bodies produced among rosettes of leaves, mingled with sex organs (particularly antheridia), and on protonema. Sexuality: variably synoicous and autoicous. Perigonial and perichetial leaves scarcely differentiated. Seta present, single, long; capsule erect, subglobose or hemispheric, wide-mouthed, with a long, fleshy neck 2--4 mm long, tapered toward the seta, hollow for the greater part of its length; stomata numerous, in upper part of capsule, each stomate with 2 guard cells; peristome and annulus absent; operculum strongly convex and bluntly umbonate or weakly convex and more or less apiculate; columella included. Calyptra small, cucullate, smooth and naked, readily deciduous. Spores tetrahedral, with densely crowded papillae.
Genus 1, species 1; rare and local in distribution across the Northern Hemisphere and widely disjunct to the southern tip of South America.
The Oedipodiaceae have been placed in the Funariales and, more commonly, in the Splachnales. Sometimes Oedipodium has been placed in the Splachnaceae because of the remarkably differentiated neck of the capsule that is somewhat similar to the expanded hypophysis of the Splachnaceae.
In addition to the distinctive capsule neck, Oedipodiaceae is further characterized by the branched-thallose protonema bearing discoid brood bodies, and also rosettes of erect-spreading leaves with stalked, discoid brood bodies often mingled with sex organs; leaves broadly rounded above a very narrow base, and leaf cells with tiny corner thickenings. The brood bodies are somewhat like those of Alophosia, of the Polytrichaceae. However, the nature of the protonema in Oedipodium and the production of brood bodies on the protonema and also in rosettes that are somewhat like the gemma cups of Tetraphis suggest a closer relationship of Oedipodiaceae to the Tetraphidaceae.
SELECTED REFERENCES
Cardot, J. & V. F. Brotherus. 1923. Botaniske Ergebnisse der schwedischen Expedition nach Patagonia und dem Feuerland 1907--09. X. Les Mousses. K. Sv. Vet. Akad. Handl. 63(10):1--74. Pls. 1-4. Kühnemann, O. & M. F. Gonçalves Carralves. 1979. Oedpodium fuegianum Kühn. et Gonç., sp. Nov. (Musci, Oedipodaceae). Darwiniana 22: 125--133. Matteri, C. M. 1988. New records for the Fuegian moss flora and the status of Oedipodium fuegianum Kühn. et Conç.-Carr. Lindbergia 14: 63-6.
