GBA onlineTHUIDIACEAE(P. Martin) Plants small to large and rather robust, forming loose to somewhat dense mats or wefts, dull light to dark green, yellowish-green to brown, or golden. Stems 1-3 pinnately branched, often rather densely tomentose; central strand present (except in Hylocomiopsis); paraphyllia scattered or dense, simple to branched, smooth to papillose. Leaves usually weakly to strongly dimorphic. Stem leaves appressed to erect-spreading, ovate or cordate (triangular) -lanceolate or subulate, apex short to long acuminate; margins plane distally, recurved or reflexed below, entire to serrulate- or crenulate-papillose; costa single, usually strong and projecting on back, percurrent to excurrent; median cells oval to isodiametric, uni- or pluripapillose on back or both surfaces, papillae low or long and often curved. Branch leaves broadly to somewhat narrowly ovate or ovate-short lanceolate, apex acute to obtuse, costa often ending below apex. Asexual structures apparently absent. Autoicous or dioicous. Perigonia lateral, leaves ovate to short ovate-lanceolate. Perichaetia lateral, leaves usually differentiated, long ovate-lanceolate to lanceolate, margins ciliate or not. Seta elongate, smooth to papillose or hispid. Capsule sub-erect to pendulous, urn cylindrical, usually curved. Operculum short to long rostrate, oblique. Peristome double, exostome teeth 16, cross-striate below, distally papillose; endostome lightly papillose, basal membrane low to high, segments 16, keeled, endostome cilia in groups of 1-3. Calyptra cucullate, naked and smooth (hispid in Pelekium velatum Mitt.). Spores spherical, smooth to more commonly papillose. Discussion. The Thuidiaceae contain sixteen genera, as defined here (Touw 2001a), and 150 or more species widely distributed in temperate and tropical regions; in sub-Saharan Africa seven genera and 22 species. There is an extensive literature discussing the delimitation of this family, and its relationship with other pleurocarpous families, some of which is listed below; the current scope of the family is as recognised by Touw (2001a). Any reference that is of value for identification is mentioned under the individual genera; Touw (1976) will be the most useful, but doesn't cover all the genera now included in the family. Study guide: Attention must be given to branching patterns, i.e., 1-, 2-, 3-pinnately branched. Paraphyllia need to be observed, both on stems with some of the leaves removed and separated from the stem in order to examine the surface ornamentation. Stem and branch leaves are required with particular attention paid to papillae, which, together with paraphyllia allow many of the sub-Saharan African species to be identified without sporophytes. In a few cases, seta ornamentation and the inclination of the capsule are required. Literature. Buck, W.R. & Crum, H. 1990. An evaluation of familial limits among the genera traditionally aligned with the Thuidiaceae and Leskeaceae. Contributions to the University of Michigan Herbarium 17: 55-69. Fang, Y. M., Koponen, T., 2001. A review of Thuidium, Haplocladium and Claopodium (Musci, Thuidiaceae) in China. Bryobrothera 6:1-82. Hedenäs, L. 1997. An evaluation of phylogenetic relationships among the Thuidiaceae, the Amblystegiaceae and the temperate members of the Hypnaceae. Lindbergia 22: 101-133. O’Brien, T.J. and Horton, D. 2000. Bryochenea (Musci: Thuidiaceae) is Cyrto-hypnum (Thuidiaceae), but B. sachaliensis is Echinophyllum (Thuidiaceae), a new genus from the Pacific rim. Bryologist 103: 509-517. Spence, J. R. 1997. A gametophytic evaluation of the Leskeaceae and related families. Journal of the Hattori Botanical Laboratory 82: 261-270. Touw, A. 1976. A taxonomic revision of Thuidium, Pelekium, and Rauiella (Musci: Thuidiaceae) in Africa south of the Sahara. Lindbergia 3: 135-195. Touw, A. 1993. Notes on tropical Asian Thuidiaceae, with two new Malesian species of Thuidium s.l. Journal of the Hattori Botanical Laboratory 74: 193-204. Touw, A. 2001a. A review of the Thuidiaceae (Musci) and a realignment of taxa traditionally accommodated in Thuidium sensu amplo (Thuidium Schimp., Thuidiopsis (Broth.) M. Fleisch and Pelekium Mitt.), including Aequatoriella gen. nov. and Indothuidium gen. nov. Journal of the Hattori Botanical Laboratory 90: 167-209. Touw, A., 2001b. A taxonomic review of the Thuidiaceae ( Musci) of tropical Asia, the western Pacific rim and Hawaii. Journal of the Hattori Botanical Laboratory 91:1-136. Touw, A. & Falter-Van den Haak, L. 1989. A revision of the Australasian Thuidiaceae (Musci), with notes on species from adjacent regions. Journal of the Hattori Botanical Laboratory 67: 1-57. Watanabe, R. 1972. A revision of the family Thuidiaceae in Japan and adjacent areas. Journal of the Hattori Botanical Laboratory 36: 171-320.
One species in sub-Saharan Africa, A. abietina Hedw., reported only from Lesotho and Natal. Plants medium to large forming stiff yellow green to brownish mats. Stems erect–ascending, unipinnately branched. Branches short and varying in length, central strand present; paraphyllia abundant on stems and branches, simple or branched, often lanceolate, papillose. Leaves of stem and branch differentiated. Stem leaves ovate to triangular, plicate, 1.1-1.8 mm long, apex acuminate, margin plane to broadly recurved; costa strong, ending below apex, cells rhombic, thick walled and strongly unipapillose dorsally, less so ventrally, sometimes curved. Branch leaves oval 0.6-0.7 mm long, cells rhombic, terminal cell with 2 or more papillae; costa ending below the apex. Dioicous. Perichaetial leaves up to 4 mm, serrate in upper leaf, longly lanceolate, apex drawn out, plicate with smooth cells. Seta 25 mm, red. Capsule 2-3mm, cylindrical, curved and inclined, annulus of large cells. Operculum conic to short rostrate. Peristome endostome with nodulose cilia and high basal membrane; cilia 2-3. Calyptra naked. Spores smooth to finely roughened 9-16?m Habitat. Xerotolerant, found in open exposed areas. Discussion. Although intermediates occur, Abietinella is distinct in the fronds forming turfs as opposed to the more common wefts in the Thuidiaceae. Differs from Thuidium in having once-pinnate ramification, more weakly ornamented paraphyllia, leaf cells ornamented on both faces and differentiated alar cells. These characters prevent a merging of Abietinella and Thuidiopsis. Literature. Touw, A. 2001a. - see general refs. Haplocladium (Müll.Hal.) Müll.Hal. Two species for sub-Saharan Africa, H. angustifolium Hampe & Müll.Hal., known from eastern and Southern Africa, and H. jacquemontii Müll.Hal. recorded only from Ethiopia. Plants small to medium forming loose mats green to yellow-brown. Stems creeping, 1-pinnate, central strand present; paraphyllia dense on stems, sparse on branches, unbranched and not papillose . Leaves on stem and branch differentiated. Stem leaves cordate to ovate with long drawn out apex 0.5–0.8 mm long, nerve excurrent, margin serrulate in upper leaf; cells oval to rectangular, prorulose on upper side. Branch leaves smaller than stem leaves, 0.3-0.5 mm long, lanceolate, margin serrulate above; costa ending in apex, cells oval to rectangular, prorulose on upper adaxial side. Autoicous. Perichaetial leaves lanceolate, 1-1.5 mm long, costa ending in apex, margin plane and serrulate. Seta 1.2-1.8 cm, smooth, red. Capsule 1.5-2 mm long, inclined asymmetric, annulus in 2-3 rows. Operculum high. Peristome endostome high, segments keeled, perforate in groups of 1-2; exostome teeth yellow to yellow-brown papillose distally. Calyptra cucullate and smooth. Spores spherical, slightly roughened. Habitat. Grows in the bottom layer of forests as well as more open situations, on rocks, soil, logs or tree bases. Discussion. Haplocladium has previously been placed in the Leskeaceae due to its smooth paraphyllia and terminal leaf cells. In both phenetic analysis of gametophyte morphology and cladistic analysis it has been shown to be close to the Thuidiaceae (Hedenäs 1997; Spence 1997). The most frequently found species, H. angustifolium, is found for instance in Mexico and India and is described in the bryophyte floras of those countries, as well as in Fang & Koponen (2001). Literature. Fang, Y. M., Koponen, T., 2001. - see family refs. Hedenäs, L. 1997 - see family refs. Spence, J. R. 1997. - see family refs. One species in sub-Saharan Africa: H. cylindricarpa Thér., recorded from Cameroon and more widely in eastern Africa. Plants medium sized forming intricate wefts, green to yellow, brown or blackish below. Stems creeping or occasionally erect and covered with brown tomentum, irregularly pinnate, sometimes bi-pinnate; central strand absent; branches often julaceous and pointed at apex; stem paraphyllia multibranched and numerous, shorter on branches. Leaves of stem and branches similar, branch leaves having shorter acumens . Stem leaves large, ovoid with long acumen, 1.4-2 mm, deeply plicate to undulate; margin plane or recurved; entire or sinuose, occasionally denticulate above; costa reaching base of acumen; cells variously shaped, elongated, especially in upper part of leaf; basal cells longer and porose, smooth or papillose. Branch leaves smaller, oval-triangular to oval round, straight or curved, 0.75-1.2 x 0.5-0.75 mm, plicate, margin plane or recurved in middle part; cells papillose with one large central papilla. Autoicous. Perichaetial leaves 7-8 mm long, costa, entire, plicate, cells 100 x 5-6 µm. Seta 2.3-3.5 mm. Capsule usually erect, rarely inclined 3-4 x 1.5 mm, brown or red-brown; annulus in 1-3 rows. Operculum conical. Peristome with exostome striate, pale yellow and papillose; endostome membrane high to low, cilia absent. Calyptra naked and smooth. Spores papillose and verruculose, green, large to 40-50 µm and multicellular in the closed capsule Habitat. Montane forests, 2250-2500 m, mostly on bark. Discussion. Has unusually large spores, becoming multicellular in closed capsules. Hylocomiopsis has a homogenous central stand, unique in the Thuidiaceae. Previously included in the Leskeaceae due to its specialised sporophyte, and in the Hylocomiaceae because of axillary hairs, paraphyllia, leaf cell ornamentation and ramification. More recent weight of opinion had accommodated Hylocomiopsis in the Thuidiaceae since the specialised sporophytes are similar to other epiphytic Thuidiaceae. Literature. De Sloover, J.L. 1976. Note de bryologie Africaine VI. – Hylocomiopsis. Bulletin du Jardin Botanique National de Belgique 46: 379-385. Eleven species for sub-Saharan Africa. Plants small to medium forming intricate, often delicate mats. Stems prostrate to arching, pinnate to bi-pinnate rarely weakly tri-pinnate, central strand present; paraphyllia mostly simple and unbranched with weak to strong intermediate cells, apical cell mostly rounded or truncate, occasionally acute; paraphyllia absent or sparse on ultimate branches. Stem leaves and branch leaves usually differentiated in shape. Stem leaves usually triangular, occasionally ovate, 0.25-1mm, apex shortly acuminate, often incurved when dry; margin weakly to strongly recurved; costa strong, ending below apex; mid-leaf cells isodiametric to slightly longer than wide, quadrate to irregular, mamillose and uni- to pluri-papillose on both leaf faces. Branch leaves smaller than stem leaves, usually ovate 0.3-0.9mm long, mid-leaf cells usually isodiametric, mamillose and uni- to pluri- papillose on both leaf faces; leaf margin plane or recurved in lower leaf; costa single, ceasing below apex. Autoicous. Perichaetial leaves lanceolate with elongate apex; costa single, leaf margin notched to longly ciliate. Seta (4-)10-20(-27) mm, smooth, occasionally papillose or hispid. Capsule 0.6-2 mm long, ovoid to elliptical, inclined to pendulous, reddish brown to orange. Operculum conic to long rostrate, 0.5-1mm. Peristome exostome with mostly high ventral lamellae, apically papillose; endostome basal membrane low to high, cilia in groups of 1-3. Calyptra 1.4-3.2 mm, cucullate and smooth though hispid and campanulate in P. velatum Mitt. Spores 8-20 (30) µm, spherical to sub-spherical, smooth to finely papillose.
Habitat. Tree trunks, logs and rocks in rain forest, 300-2500 m. Discussion. In recent years the separation within Thuidium of the small monoicous from the large dioicous species has stimulated much discussion and nomenclatural changes. After the transfer of several species out of the genus (Touw 2001a) a sensible group remains which sees the merging of Pelekium (sensu lato) and Cyrto-hypnum to form Pelekium (Touw 2001a). Pelekium is distinguished from Thuidium and Thuidiopsis by its small size and autoicous breeding system. Literature. Touw, A. 1976. - see family refs. Touw, A. 2001a. - see family refs. One species, R. subfilamentosa (Besch.) Wijk & Margad., recorded from Kenya, Tanzania, Malawi, Zimbabwe, South Africa and Madagascar. Plants small, forming coarse thin to dense mats, dull olive green, yellowish, or golden to reddish-brown. Stems creeping and spreading, pinnately branched; central strand weak; rhizoids often produced on terminal branch tips; paraphyllia abundant on stems, few to absent on branches, simple or weakly branched, papillose with oblate cells. Leaves erect when dry, spreading when wet, stem and branch leaves dimorphic. Stem leaves short to long lanceolate from an ovate base, 0.4-0.8(-0.9) mm long to 0.6 mm wide, plicate, apex usually abruptly long acuminate, base weakly decurrent; margins reflexed, crenulate; costa strong, percurrent to short excurrent; laminal cells similar throughout, oval to quadrate-rounded, strongly bulging, uni- or pluripapillose. Branch leaves ovate, to 0.65 mm long, apex acute to bluntly short acuminate. Autoicous. Perichaetial leaves glossy pale yellow, setaceous from an ovate base, to 3.5 mm long. Seta (5-)8-15 mm or more long, slightly twisted, smooth. Capsule inclined, urn ovoid-short cylindrical, (0.4-)0.9-1.5 mm long; annulus present. Operculum rostrate, oblique. Peristome with exostome teeth finely cross-striate below, distally papillose; endostome basal membrane high, cilia 1-2. Calyptra cucullate, naked and smooth. Spores spherical, lightly papillose. Habitat. In montane forests on tree bases, rocks and occasionally terrestrial, 1200-1800m. Discussion. Previously included in Thuidium and Haplocladium. Distinct from Pelekium by bulging leaf cells on both sides of leaf and larger paraphyllia which have oblate cells. Literature. Touw, A. 1976. - see family refs. Touw, A. 2001a. - see family refs. Thuidiopsis (Broth.) M.Fleisch. One species for sub-Saharan Africa, T. sparsa Hook.f. & Wilson, reported for the Comoros islands. Plants medium sized, pale to yellow-green. Stems spreading or ascending, mostly bi-pinnate; central strand present; paraphyllia unbranched and numerous on stem and lower part of branches, papillose. Leaves of stem and branch differentiated. Stem leaves triangular to cordate, 1-1.5 mm long, apically contracted to form acute acumen; leaf margin recurved below, plane above, usually entire; costa strong, ceasing below apex; median leaf cells mostly isodiametric, abaxially unipapillose to mostly pluripapillose, adaxially mamillose and mostly smooth. Branch leaves ovate to ovate-oblong, to 0.3 mm long, median cells pluripapillose to smooth; costa reaching 3/4 way up leaf. Dioicous. Perichaetial leaves to 2 mm, acuminate apex, margin mostly ciliate; costa usually weak, sometimes strong and excurrent, cells smooth. Capsule to 2.5 mm long, inclined to sub-pendulous. Peristome with yellowish to orange-brown exostome with high ventral lamellae; endostome yellowish, brownish or orange, well developed, basal membrane high, cilia in groups of 2-4. Operculum to 2 mm conical to rostrate. Calyptra cucullate, smooth and fringed at base. Spores 8-16 µm, smooth or minutely papillose. Habitat. Distributed in a variety of habitats from open forest communities, on boulders, base of trees or dead wood. Discussion. Differs from Thuidium by having simple paraphyllia and leaf cells ornamented on both leaf faces. Has characteristic long paraphysal hairs fringing base of calyptra and strongly incurved stem leaves. Literature. Touw, A. 2001a. - see family refs. Thuidium Bruch, Schimp. & W.Gümbel Five species in sub-Saharan Africa, mainly in eastern and southern Africa and the Indian Ocean islands; only one recorded also for west Africa (T. involvens ssp. thomeanum). Plants medium to large forming loose to dense coarse mats, pale yellow-green to brownish green. Stems and branches spreading to loosely spreading, 1-3 pinnately branched; central strand present and sometimes well developed; paraphyllia mostly large and branched; weakly to strongly papillose and varying from numerous along stem and branches to few or scattered along stems and often absent on branches. Leaves of stems and branches differentiated, sometimes strongly dimorphic. Stem leaves broadly ovate/cordate or triangular, short to long lanceolate, 0.4-1.7 mm long; bi-plicate and sometimes short decurrent, apex broadly to narrowly short to long acuminate, occasionally ending in a long hyaline capillary hair point; margins often strongly incurved or recurved to reflexed at base, partially inflexed or erect above, serrate or serrulate in distal 2/3; costa strong ending below acumen or long excurrent; median cells oval-rhombic to +/- elongate or subhexagonal to subquadrate-rounded; uni-papillose or pluri-papillose, papillae projecting on dorsal lamina or both sides, somewhat erect to curved; basal cells +/- elongate. Branch leaves smaller, ovate-short lanceolate, up to 0.75 mm long, margins plane to erect, entire, costa mostly ending below the acumen. Dioicous. Perichaetial leaves elongate, ovate-triangular, lanceolate to oblong-lanceolate; apex short or more commonly gradually to abruptly long acuminate; costa single, margins entire to ciliate. Seta 7-40 mm long, papillose or smooth, reddish orange to brown. Capsule 0.6-3 mm, inclined to pendant, urn cylindrical or short to +/- long ovoid or ovoid cylindrical; annulus in 2-3 rows; peristome with exostome teeth cross-striate, papillose distally; endostome basal membrane high, segments keeled, cilia 1-3(-4). Operculum conic to conic- short to long rostrate, oblique. Calyptra cucullate, naked and smooth. Spores spherical, smooth to lightly papillose or papillose. Habitat. Although found also in grassland and scrub, predominantly in mountain forest between 450-2000 m. Overall range from sea level to 3500 m. Mostly on tree trunks and decaying wood, but also found on soil, rocks, low branches and litter. Discussion. This genus is now restricted to the large dioicous species. Thuidium has distinct bi- or tri-pinnate fronds and large paraphyllia. The genus presents difficulties in differentiation of the species which have slight, but consistent, differences. Literature. Fang, Y. M., Koponen, T., 2001. - see family refs. Touw, A. 1976. - see family refs. Touw, A. 2001a. - see general refs. Click here for pdf file accepted 10.01.2003 |
