Stegonia latifolia

(Schwägrichen) Venturi ex Brotherus

Laubm. Fennosk., 145. 1923,.

Basionym: Weissia latifolia Schwägrichen in J. A. Schultes, Reise Glockner 2: 362. 1804
Synonyms: Pottia latifolia (Schwägrichen) Müller Hal.
Treatment appears in FNA Volume 27. Treatment on page 604. Mentioned on page 632.
Revision as of 21:05, 16 December 2019 by FNA>Volume Importer

Seta (2–)4–12 mm. Capsule stegocarpous, exerted, ovate-cylindric, to 1–2 mm, operculum short-rostrate, peristome teeth rudimentary or 16, cleft to near base. Also keying to this species is a distinctive new species described but not formally named by B. M. Murray (1992) for Alaska; a formal description will be provided in another publication. The new species shares with Stegonia the characteristic rudimentary peristome, ovate leaf with a triangle of clear cells apically and abaxial cell walls more thickened than the adaxial, and bulliform cells on the adaxial surface of the costa, but possesses three kinds of adaxial costal lamellae: (1) rounded lamellae typical of Pterygoneurum, (2) additional, serrate, papillose lamellae near the leaf apex just distal to the rounded lamellae, and (3) on small leaves only lamellae consisting entirely of bulliform, nonpapillose cells.

Distribution

V27 870-distribution-map.gif

Widespread in Northern Hemisphere, Antarctic.

Discussion

Varieties 2 (2 in the flora).

Stegonia latifolia is uncommon but distinctive. In section, the leaves show a characteristic thickening of the abaxial superficial cell walls, similar to that of some species of Acaulon, a genus which differs in the red laminal color reaction to KOH and spheric capsules.

Selected References

None.

Key

1 Leaves muticous, costa ending before the apex Stegonia latifolia var. latifolia
1 Leaves awned, costa excurrent in most leaves as a hyaline hair point Stegonia latifolia var. pilifera