BFNA Title: Drummondia
Drummondia - Orthotrichaceae
9. DRUMMONDIA Hooker in T. Drummond, Musci Bor. Am. (Rocky Mts.) n. 62. 1828, conserved name * [For Thomas Drummond (ca. 1780--1835), Scottish botanist who collected extensively on two expeditions to North America]
Dale H. Vitt
Plants of medium size. Stem leaves erect-appressed and stiff when dry, oblong or lanceolate, obtuse, acute or cuspidate, channeled, concave; margins entire; costa strong; basal laminal cells rectangular to quadrate; distal laminal cells small, ± rounded-quadrate. Perichaetial leaves longer, clasping seta; gemmae not produced. Sexual condition dioicous or autoicous. Seta less than 5 mm. Capsule ovate to oblong, neck absent; stomates absent or superficial in lower portion of capsule; peristome single, of 16 rudimentary, truncate, smooth teeth. Calyptra cucullate, long-conic, smooth, naked. Spores less than 100 µm.
Species 6 (1 in the flora): North America, Mexico, South America, Asia.
Branched, prostrate stems and the cucullate calyptra characterize this genus.
1. Drummondia prorepens (Hedwig) E. Britton, Mem Torr. Bot. Cl. 4: 180. 1894
Gymnostomum prorepens Hedwig, Spec. Musc. 35. 3 f. 1--4. 1801; Drummondia canadensis (Macoun & Kindberg); D. clavellata (Hooker & Greville) Hooker; Drummondia clavellata var. canadensis Macoun & Kindberg
Plants olive, dark green, or yellow-brown. Stem leaves spreading to wide-spreading when moist, broadly-lanceolate to oblong-lanceolate, 1.1--1.8 mm, acute or obtuse, sometimes tips incurved, concave; margins entire; costa ending just below apex, broadly channeled; basal laminal cells similar to distal cells; distal laminal cells 6--10 µm wide; alar cells yellow, ± inflated at marginal insertion. Perichaetial leaves closely clasping seta, basal cells rectangular, usually yellowish, up to 2 mm, broadly-lanceolate, acute or acuminate. Sexual condition autoicous. Seta 2--3.5 mm, dextrose. Capsule ovate to ovate-oblong, 0.9--1.3 mm, wrinkled when old and dry, sharply contracted to seta, not constricted beneath mouth; stomates none; peristome teeth each 3--6 cells high. Spores 70--100 µm in longest dimension, rounded-quadrate to elliptic-rectangular, multicellular, brown, almost smooth.
Usually on trunks and branches of deciduous trees in dry, upland forest or cedar glades, sometimes on conifers or on logs; N.B., N.S., Ont., Que.; Ala., Ark., Conn., Del., D.C., Ga., Ill., Ind., Iowa, Ky., Kan., Maine, Md., Mass., Mich., Miss., Mo., Neb., N.H., N.J., N.Y., N.C., Ohio, Okla., Pa., S.C., Tenn., Vt., Va., W.Va. Endemic to eastern North America.
This species cannot be confused with any other moss. The long-creeping stems with numerous, erect branches bearing terminal sporophytes are characteristic. This habit, combined with the cucullate calyptrae, smooth, ovate capsules with 16, truncate exostome teeth, the lack of stomates, and the undifferentiated basal leaf cells is absolutely diagnostic.