Selaginella hansenii |
Selaginella scopulorum |
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Hansen's spike-moss |
cliff selaginella, cliff spikemoss, compact spikemoss, Rocky Mountain spike-moss |
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Habit | Plants terrestrial, forming loose to clustered mats. | Plants terrestrial or on rock, forming cushionlike or rather loose mats. |
Stems | not readily fragmenting, prostrate, upperside and underside structurally different, irregularly forked, branches determinate, tips upturned. |
decumbent or creeping, not readily fragmenting, irregularly forked, without budlike arrested branches, tips straight; main stem upperside and underside structurally slightly different, conspicuously or inconspicuously indeterminate, lateral branches radially symmetric, conspicuously determinate, strongly ascending, 1–2-forked. |
Leaves | with underside leaves slightly longer and narrower than upperside leaves, otherwise monomorphic, not clearly ranked, tightly appressed, ascending, green or green with red spots, or reddish, linear-lanceolate (underside) to linear-triangular (upperside), (2–)3–4.5 × 0.5–0.6 mm; abaxial ridges present; base abruptly adnate, pubescent (sometimes glabrous); margins ciliate, cilia white to white opaque, strongly appressed and ascending, 0.03–0.1 mm; apex with bristle white to white-opaque, 0.5–1.4 mm (those on underside leaves sometimes 1/4–1/2 longer than those on upperside leaves). |
monomorphic, in poorly defined pseudowhorls of 4 or 6, tightly appressed, ascending, green, linear-lanceolate to linear, in lateral ranks sometimes falcate, 2.5–4(–4.3) X 0.5–0.75 mm (upperside leaves smaller than underside, smaller also on ascending buds); abaxial ridges present; base (on main stem) decurrent, oblique, and glabrous on underside leaves, slightly decurrent to adnate, oblique, and glabrous or rarely puberulent on upperside leaves; margins usually short-ciliate, cilia transparent, spreading or ascending at base, denticulate and ascending on distal 2/3, 0.02–0.07(–0.15) mm; apex plane or sometimes slightly keeled, obtuse to attenuate, abruptly bristled; bristle whitish, transparent to opaque, with few teeth or smooth, 0.5–1.1 mm. |
Strobili | solitary, 5–7 mm; sporophylls ovate-deltate to ovate-triangular, abaxial ridges not prominent, base glabrous, margins short-ciliate, apex bristled. |
solitary, (0.5–)1–3(–4.5) cm; sporophylls ovate-lanceolate, lanceolate, or seldom ovate, usually tapering toward apex, abaxial ridges well defined, base glabrous, margins proximally short-ciliate to denticulate, lacking cilia apically, apex usually attenuate or slightly keeled, short-bristled. |
Rhizophores | borne on upperside of stems, throughout stem length, 0.25–0.45 mm diam. |
borne on upperside of stems, throughout stem length, 0.25–0.45 mm diam. |
Selaginella hansenii |
Selaginella scopulorum |
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Habitat | Cliffs and rocky slopes or on igneous rock | Rocky alpine tundra, subalpine meadows, dry cliffs, rocky slopes, rock crevices, granitic outcrops and ledges, sandstone outcrops, in soil pockets among rocks, or sandy or granitic soil |
Elevation | 330–1350 m (1100–4400 ft) | 700–3700 m (2300–12100 ft) |
Distribution |
CA
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AZ; CA; CO; ID; MT; NM; OR; UT; WA; WY; AB; BC
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Discussion | Leaf dimorphism in Selaginella hansenii is only slightly and inconsistently expressed; the upperside leaves tend to be more lanceolate, short, and slightly thick, whereas the underside leaves tend to be more linear, longer, and thinner, but in some specimens the leaves are monomorphic. Red leaves are rare within Selaginella subg. Tetragonostachys, otherwise found in the flora only occasionally in S. rupestris. Such leaves are more common in S. steyermarkii Alston from southern Mexico and Guatemala and S. sartorii Hieronymus from Mexico. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Selaginella scopulorum is a member of the S. densa complex, in which there is a clear need for more systematic studies. Some specimens of S. scopulorum from Montana, Wyoming, and Colorado have more conspicuous whitish bristles than those elsewhere and are difficult to distinguish from S. densa. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 2. | FNA vol. 2. |
Parent taxa | Selaginellaceae > Selaginella > subg. Tetragonostachys | Selaginellaceae > Selaginella > subg. Tetragonostachys |
Sibling taxa | ||
Synonyms | S. densa var. scopulorum, S. engelmannii var. scopulorum | |
Name authority | Hieronymus: Hedwigia 39: 301. (1900) | Maxon: Amer. Fern J. 11: 36. (1921) |
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