|
BFNA
Title: Timmiaceae |
|
TIMMIACEAE Schimper Guy R. Brassard Plants acrocarpous, large, (1--)2--9(--13) cm, in compact or loose tufts, brownish proximally, bright to yellowish green distally. Stems stiff, erect, mostly unbranched, in cross-section with a cortical region of small, thick-walled cells, a parenchyma of larger, thin-walled cells, and a distinct central strand; rhizoids abundant, especially on the proximal stems and in the leaf axils, dark reddish black, coarsely papillose, ca. 15--35 µm wide. Leaves crisped to imbricate (and occasionally inrolled) when dry, erect-patent to spreading when moist, lanceolate or long-lanceolate, with a sheathing, entire base occupying the proximal 1/3--1/6 of the leaf, and a non-sheathing, serrate limb, (1.5--)2--8(--12) mm, 0.5--1.2 mm wide at mid-limb; costa strong, single, subpercurrent to excurrent, in cross-section (mid-limb) with large guide cells, two bands of stereids, and enlarged abaxial and adaxial cells; cells of limb lamina irregularly isodiametric or quadrate, smooth, papillose or mamillose on adaxial and abaxial surfaces; cells of the sheath lamina rectangular, longer and narrower near the margins, shorter and broader near the limb-sheath transition, smooth on the adaxial surface, smooth or with a series of linearly-arranged, large round papillae on the abaxial surface of the lumens. Sexual condition monoicous or dioicous; male gametophyte (in dioicous taxa) monopodial, with the stem continuing growth through terminal perigonia; paraphyses few, of 10--15(--40) cells, filiform, with fusiform tips; archegonia 1--6 per perichaetium, ca. 1--2 mm; antheridia 5--40 per perigonium, ca. 1--2 mm. Seta terminal, elongate, erect, single or double, 1.4--3.5 cm. Capsule ca. 2.5--3 ´ 1--1.5 mm, pendulous to nearly erect, ovate to oblong-cylindric, smooth or broadly plicate; annulus large, revoluble; operculum hemispheric or conic, with a distinct mamilla at the tip; exothecial cells with smooth or sinuose walls, stomata numerous on the neck or over the entire urn; peristome diplolepideous; exostome of 16 lanceolate teeth sometimes united near the base, 0.5--1 mm, yellow in proximal half, pale or hyaline distally, smooth or papillose proximally, strongly vertically barred and papillose distally, with prominent projecting lamellae on the interior surface; endostome about the same height as the exostome, hyaline or yellowish, with a high basal membrane about half the height of the exostome, and 64 irregularly anastomosing, nodose cilia papillose externally and smooth or appendiculate on the interior surface. Calyptra linear-cylindrical. Spores round, finely papillose, pale yellow or brown, 13--22 µm. Genera 1, species 4 (1 genus, 4 species in the flora): North America, Eurasia, n Africa, Hawaii, New Zealand. A small, taxonomically isolated family consisting of a single genus, Timmia. 1. TIMMIA Hedwig, Spec. Musc. Frond. 176. 1801 • [For Joachim Christian Timm, 1734-1805, botanist and Burgermeister of Malchin, Mecklenberg, Germany] Grevilleanum L.C. Beck & E. Emmons 1826, not J. A. Salisbury 1809 Species 4 (4 in flora): all in Arctic, boreal, montane or temperate regions of North America, Eurasia, and n Africa; one species occurs in Hawaii, and one is bipolar, disjunct to New Zealand. SELECTED REFERENCES Brassard, G. R. 1979. The moss genus Timmia. 1. Introduction, and revision of T. norvegica and allied taxa. Lindbergia 5: 39--53. Brassard, G. R. 1980. The moss genus Timmia. 2. Sect. Timmiaurea. Lindbergia 6: 129--136. Brassard, G.R. 1984. The moss genus Timmia. 3. Sect. Timmia. Lindbergia 10: 33--40. 1. Cells at the leaf insertion not hyaline and fragile, the leaves not readily breaking away from the stem. 2. Leaf sheaths bright, clear orange (appearing red when still on the stem); cilia of the endostome non-appendiculate; dioicous [Sect. Timmiaurea Brassard] 1. Timmia austriaca 2 Leaf sheaths pale, uncoloured or yellowish; cilia of the endostome appendiculate; monoicous [Sect. Timmia] 2. Timmia megapolitana 1. Cells at the leaf insertion hyaline and fragile, the leaves readily breaking away from the stem [Sect. Norvegicae Brassard]. 3. Abaxial surface of the mid-limb cells mamillose and pluripapillose (as seen in cross-section) 4. Timmia sibirica 3. Abaxial surface of the mid-limb cells non-mamillose and non-papillose 3. Timmia norvegica 1. Timmia austriaca Hedwig, Spec. Musc. Frond. 176, pl. 42, fig. 1-7. 1801 Timmia arctica Kindberg; T. austriaca var. arctica (Kindberg) Arnell; T. austriaca var. brevifolia Renauld & Cardot; T. austriaca var. papillosa Hesselbo Plants without deciduous distal leaves. Leaf apex acute (but with terminal 4--5 cells often truncated); costa subpercurrent; sheath orange but appearing red when still on stem; limb green, pellucid; limb-sheath transition abrupt, sharply angled; limb margins strongly dentate in distal 1/3--1/2, less dentate to entire proximally, occasionally crenulate or entire throughout; limb lamina cells 8--14(--16) × 8--12(--13) µm, with low conical or rounded mamillae on the adaxial surface, abaxial surface smooth; distal sheath lamina cells smooth or with 1--6(--8) large round, often verrucose papillae over the abaxial surfaces of lumen; cells at leaf insertion not hyaline and fragile; abaxial surface of costa limb smooth, toothed or papillose near apex, adaxial cells with conical or rounded mamillae. Sexual condition dioicous; perichaetial leaves more strongly dentate than vegetative leaves, sheath up to half the leaf length. Calyptra without longitudinal split, not persistent on the seta. Capsule spirally plicate (even when young and operculate); exothecial cell walls sinuose; stomata mostly on the neck; endostome cilia without appendiculations on the interior surfaces. Sporophytes sporadic throughout the range, but more frequent in non-Arctic regions; in many habitats, from dry exposed ridges with stunted forms, to wet river edges or forested valleys with tall and robust forms; widely distributed in Arctic-montane regions of North America, disjunct in Michigan; 0--3000 m; Greenland; Alta., B.C., N.B., Nfld., N.W.T., Nunavut, Que., Sask., Yukon; Alaska, Calif., Colo., Idaho, Mich., Mont., Nev., N.Mex., Oreg., S.Dak., Wash., Wyo.; Eurasia (Iceland, U.K., Scandinavia, Alps, Pyrenees, Italy, Greece, Caucasus, Russia). A polymorphic yet remarkably well-defined species, Timmia austriaca has the most well-delimited sheath of all Timmia taxa, with an abrupt change in color and sharp angle at the limb-sheath transition, and it is the only taxon where the costa widens slightly just at the limb-sheath transition. Its distinct habit and leaf angularity, dioicous sexuality, non-appendiculate endostome cilia, and orange sheaths separate it from T. megapolitana, while its habit, leaf angularity, and non-deciduous leaves will separate it from T. norvegica and T. sibirica. The perigonial leaves are short and broad, consisting mostly of sheath. 2. Timmia
megapolitana Hedwig, Spec. Musc. Frond. 176. 1801
F Plants without deciduous distal leaves. Leaf apex acute; costa subpercurrent; sheath clear or yellowish; limb green, pellucid; limb-sheath transition abrupt, not sharply angled; limb margins strongly dentate in distal half, with fewer and smaller teeth below, and a few small sharp teeth at limb-sheath transition; limb lamina cells (5--)7--16(--21) × (6--)7--12(--14) µm, with low rounded or flattened mamillae on the adaxial surface, abaxial surface smooth; abaxial surfaces of sheath lamina cells smooth or with 1--6 papillae over lumen; cells at leaf insertion not fragile and hyaline; abaxial surface of limb costa smooth (rarely papillose near leaf apex), adaxial cells with rounded or somewhat flattened mamillae. Sexual condition monoicous; perichaetial leaves narrower than vegetative leaves. Calyptra with a median longitudinal split, sometimes persistent on the neck of the capsule or seta. Capsule plicate or puckered when dry; exothecial cells with non-sinuose walls; stomata on urn; endostome cilia with numerous spine-like or branched-stellate appendiculations on the interior surfaces. Subspecies 2 (2 in the flora): North America; Eurasia; n Africa; Hawaii. Timmia megapolitana is a distinct species within the genus, separated by its monoicous sexuality, distinct but pale leaf sheaths, and elaborately appendiculate endostome cilia. 1. Cells of mid-limb lamina (8--)9--12(--14) µm wide; cells of distal part of leaf sheath papillose; calyptra often remaining attached to seta at base of capsule 2a. Timmia megapolitana subsp. megapolitana 1. Cells of the mid-limb lamina (6--)7--10(--12) µm wide; cells of distal part of leaf sheath smooth; calyptra not persistent on seta 2b. Timmia megapolitana subsp. bavarica 2a. Timmia
megapolitana Hedwig subsp. megapolitana
Timmia cucullata Michaux Cells of mid-limb lamina (8--)9--12(-- 4) µm wide (mean 10.5 µm); cells of distal part of leaf sheath with 1--6 papillae on the abaxial surface. Calyptra often remaining attached to seta at base of capsule. Almost always with sporophytes. Most often in deciduous forests, on humus in moist, shady calcareous sites, northwards in forested localities, especially along major rivers, and as an adventive in disturbed sites such as lawns, golf courses or cemeteries; 0--500 m; Alta., B.C., Man., N.W.T., N.S., Ont., Que., Sask., Yukon; Alaska, Ark., Conn., Ill., Ind., Iowa, Ky., Mass., Mich., Minn., Mo., Mont., Nebr., N.J., N.Y., Pa., S.Dak., Tenn., Vt., Va., Wis.; Eurasia (Netherlands, Germany [extinct], Finland, Russia, China).
Timmia megapolitana subsp. megapolitana is the only taxon in the genus that is not an Arctic or montane moss; it occurs primarily in temperate regions, and sporadic in the boreal region. It is also the only taxon occurring in man-made habitats. The common name Indian Feather Moss reflects the resemblance of the erect, persistent calyptra to the feather headdresses used by some North American Indians. 2b. Timmia megapolitana subsp. bavarica (Hessler) Brassard, Lindbergia 10: 34. 1984 Timmia bavarica Hessler; T. megapolitana var. bavarica (Hessler) Bridel Cells of the mid-limb lamina (6--)7--10(--12) µm wide (mean 8.5 µm); cells of distal part of leaf sheath non-papillose on abaxial surface (rarely papillose in non-North American specimens). Calyptra not persistent on seta. Often with sporophytes. Most often in mesic, calcareous, open or well-vegetated Arctic-montane sites, or in nutrient-rich sites such as the bases of cliffs or around large boulders; 0--3000 m; Greenland; Alta., B.C., Man., N.W.T., Nunavut, Ont., Que., Sask., Yukon; Alaska, Ariz., Colo., Idaho, Mont., Nev., N.Mex., Utah, Wyo.; Mexico; Eurasia (n and c Europe, Greece, Caucasus, China, India, Japan); n Africa (Algeria); Atlantic Islands (Iceland); Pacific Islands (Hawaii). 3. Timmia norvegica J.E. Zetterstedt, Oefvers. Förh. Kongl. Svenska Vetensk.-Akad. 19: 364. 1862. Plants with deciduous, longer distal leaves with a less well-developed sheath. Leaf apex acute or acuminate; costa ending a few cells below apex or excurrent; sheath clear in the distal leaves, orange-brown to reddish-black in the proximal leaves; limb green, pellucid; limb-sheath transition gradual; limb margins coarsely dentate in distal 1/3--1/2, slightly toothed, crenulate or ± entire proximally; limb lamina cells 6--6(--18) × 6--14 µm, with tall rounded mamillae on the adaxial surface, abaxial surface smooth; sheath lamina cells with (0--)1--6(--8) large round, verrucose papillae over abaxial surface of the lumen; cells at leaf insertion abruptly differentiated into 1 to a few rows of fragile, hyaline cells; limb costa papillose on abaxial surface, or toothed near the apex, adaxial cells with tall bottle-shaped mamillae. Sexual condition dioicous; perichaetial leaves longer and more evenly tapering than stem leaves, sheath poorly developed. Calyptra unknown. Capsule non-plicate; exothecial cells with extremely sinuose walls; stomata on neck and proximal urn; endostome cilia with numerous short blunt appendiculations on the interior surfaces. Varieties 2 (2 in the flora): North America, Eurasia, New Zealand. Timmia norvegica is related to T. sibirica, with which it shares the important character of fragile leaf bases; however, the papillosity of the limb in T. sibirica is a strongly differentiating character. T. norvegica differs from T. austriaca and T. megapolitana by having fragile leaf bases, heterophyllous leaves, and less well delimited leaf sheaths. 1. Leaves 3--8(--12) mm, 0.8--1.1 mm wide at mid-limb; cells of mid-limb lamina (8--)9--16(--18) × (8--)9--14 µm; base of costa dark; never with loose clusters of linear leaves at stem tips 3a. Timmia norvegica var. norvegica 1. Leaves 2--6 mm, 0.5--0.6 mm wide at mid-limb; cells of mid-limb lamina 6--10(--11) × 6--9(--10) µm; base of costa pale; stem tips often with loose deciduous clusters of almost linear leaves 3b. Timmia norvegica var. excurrens 3a. Timmia
norvegica J.E. Zetterstedt var. norvegica Plants robust. Leaves 3--8(--12) mm, 0.8--1.1 mm wide at mid-limb; cells of mid-limb lamina (8--)9--16(--18) × (8--)9--14 µm; costa ending below apex, papillose on abaxial surface of sheath and limb; base of costa dark and swollen, more strongly attached to stem than is the lamina; with distal leaves often larger and deciduous, but never with loose clusters of linear leaves at stem tips. Sporophytes extremely rare. Wet calcareous sites such as seepage slopes, moist crevices or cliff ledges, snow patches, edges of small creeks and ponds in Arctic-montane areas, often intermixed with other mosses, including Timmia sibirica, T. norvegica var. excurrens, and T. austriaca; 0--3600 m; Greenland; Alta., B.C., Man., Nfld., N.W.T., Nunavut, Que., Yukon; Alaska, Colo., Mont.; Eurasia (U.K., Scandinavia, Alps, Russia); Atlantic Islands (Iceland); Pacific Islands (New Zealand). Only three sporulating specimens of Timmia norvegica var. norvegica are known (one from Alaska). The deciduous leaves undoubtedly act as vegetative propagules. 3b. Timmia norvegica var. excurrens Bryhn, Rept. Second Norweg. Arctic Exped. “Fram” 1898--1902. 11: 121. 1906 Timmia comata Lindberg & Arnell; T. norvegica var. comata (Lindberg & Arnell) H. A. Crum. Plants generally smaller and more delicate than those of var. norvegica. Leaves 2--6 mm, 0.5--0.6 mm wide at mid-limb; cells of mid-limb lamina 6--10(--11) × 6--9(--10) µm; costa excurrent, smooth on abaxial surface of sheath, smooth or slightly papillose on abaxial surface of the limb, with one--several teeth at back near the apex; base of costa pale and not strongly attached to the stem; stem tips often with loose deciduous clusters of almost linear leaves (ca. 3 × 0.1--0.2 mm). Calcareous areas, often on shaded limestone cliffs near rivers in Arctic and boreal regions, intermixed with other mosses, including other taxa of Timmia; 0--1500 m; Greenland; Nfld., N.W.T., N.S., Que., Yukon; Alaska; Eurasia (Scandinavia, Switzerland, Poland, and Russia); Atlantic Islands (Iceland). Timmia norvegica var. excurrens is also known as a Quaternary subfossil from N.Y. and Vt. This variety is not known to occur with sporophytes, but the deciduous leaves no doubt act as vegetative propagules. 4. Timmia sibirica Lindberg
& Arnell, Kongl. Svenska Vetenskapsakad. Handl. 23(10): 24. 1890
F Timmia norvegica var. crassiretis Hesselbo Plants with deciduous longer distal leaves with a less well-developed sheath. Leaf apex acute to slightly acuminate; costa percurrent or subpercurrent; sheath clear in the distal leaves, clear or dark reddish-black in the proximal leaves; limb green, non-pellucid; limb-sheath transition gradual; limb margins dentate in distal 1/3--1/2, crenulate or slightly toothed proximally, limb lamina cells (8--)11--18(--22) × (9--)10--19 µm, mamillose and with 2--4 papillae on the adaxial surface, with 2--4 papillae and generally also mamillose on the abaxial surface; cells of the sheath lamina with (0--)1--8(--10) large round, often verrucose papillae over the abaxial surface of the lumens; cells at leaf insertion abruptly differentiated into 1 to a few rows of fragile, hyaline cells; limb costa with the abaxial cells uni- or pluripapillose, and the adaxial cells mamillose and pluripapillose. Dioicous. Perichaetial leaves longer and more evenly tapering to the apex than stem leaves, with the sheath poorly developed. Perigonial leaves shorter than stem leaves, consisting mostly of the sheaths, abruptly apiculate. Calyptra without longitudinal split, not persistent on the seta. Capsule ± non-plicate (only immature ones known); exothecial cells with very sinuose walls; stomata on the neck; endostome cilia with numerous blunt appendiculations on the interior surfaces. Only one sporulating specimen is known (from Alaska), but the capsules are immature. Wet or moist, predominantly calcareous sites, often near small streams, on seepage slopes, near snowmelt areas, or in depressions in open tundra; frequently intermixed with other mosses, including other species of Timmia; 0--1500 m; Greenland; Alta., B.C., Nfld., N.W.T., Que., Yukon; Alaska; Europe (Norway, Russia). Timmia sibirica is a very distinct species: the limb lamina and limb costa cells that are mamillose and pluripapillose on both surfaces are unique within the genus. It is an Arctic species, rare south of 65° N. Timmia sibirica has somewhat larger leaf cells than T. norvegica (and the largest cells of any Timmia taxon), and it has deciduous leaves that can aid in vegetative dispersal. |
