Janssen, Janssen & Rakotondrainibe, 2008

Janssen, Thomas & Rakotondrainibe, France, 2008, A revision of the indusiate scaly tree ferns (Cyatheaceae, Cyathea subgen. Alsophila sect. Alsophila) in Madagascar, the Comoros and the Seychelles, Adansonia (3) 30 (2), pp. 221-376 : 277-281

18. Cyathea serratifolia Baker

( Figs 1C ; 17 ; 46F ; 49B )

Journal of Botany 22: 139 (1884); Christensen, Dansk Botanisk Arkiv 7: 18, pl. 3 figs 9-12 (1932); Tardieu in Humbert, Flore de Madagascar et des Comores, IVe famille, Cyathéacées : 4 (1951). — Alsophila serratifolia (Baker) R.M.Tryon, Contributions from the Gray Herbarium 200: 31 (1970). — Type: Madagascar, North-East, Humblot 278 (holo-, K! [K000009922]; iso-, B!, BM!, G!, K!, MO!, NY!, P! [4 sheets], TAN!). Cyathea regularis Baker , Journal of the Linnean Society

25: 349 (1890). — Type: Madagascar, East Androna ,

Baron 5604 (holo-, K! [2 sheets: K000009924, -25];

iso-, P! [fragment]). ADDITIONAL MATERIAL EXAMINED. — Madagascar. Toamasina, Ambatovy forest, 18°49’S, 48°18’E, 1088 m, 14.I.2005, Antilahimena et al. 3137 (MO, P, TAN). — Idem, 1102 m, 11.II.2005, Antilahimena et al. 3374 (P). — Forêt entre Volotaraina et Ambodirofia, 9.XI.1942, Cours 1724 (P). — De Manakambahiny à Nonokambo, 17°46’S, 48°39’E, 1200 m, 16.I.1945, Cours 2353 (P). — Antsiranana, Ambatosoratra, 14°32’S, 49°42’E, 6.I.1949, Cours 3305 (P). — Au pied de l’Anjanaharibe, 14°42’30’’S, 49°27’30’’E, 850 m, 15.XII.1950, Cours 3628 (P), 3629 (K). — Antananarivo, Anjozorobe, 18°23’S, 47°53’E, 20.IX.1971, Cremers 1853 (BR). — Toamasina, Andasibe, Analamazaotra, 18°56’S, 48°26’E, XII.1905, D’Alleizette 12 (P). — Idem, X.1906, D’Alleizette 218 (P). — Idem, X.1905, D’Alleizette 227 (P). — Moramanga, Anosibe, 18°55’S, 48°03’E, 6.IX.1942, Decary 18275 (BR, K, MO, P). — Manantenina, Beondroka, 14°25’S, 49°50’E, 850 m, 12.XI.1989, Deroin et al. 15 (P). — Toamasina, massif de l’Andrangovalo, SE Lac Alaotra, 17°40’S, 48°45’E, 1000 m, X.1937, Humbert et al. 17614 (P). — Andapa, massif de Marojejy (Nord-Est), 14°31’30’’S, 49°35’30’’E, 450-800 m, 1948, Humbert et al. 22058 (MO, P). — Mont Ambatosoratra, N d’Ambalavoniho et de Belaoka, 14°32’S, 49°42’E, 1100-1300 m, I.1949, Humbert et al. 22877 (K). — Massif du Marojejy, col de Doanyanala, 14°28’S, 49°32’E, 800-900 m, 1949, Humbert 23089 (K, P). — Toamasina, RNI Betampona, Rendriendry, 17°55’48’’S, 49°12’E, 310-580 m, 6.XI.2004, Janssen et al. 2537 (MO, P, TAN). — Idem, piste entre les sommets Mahasolatra et Betampona, 17°54’36’’S, 49°13’12’’E, 580- 550 m, 6.XI.2004, Janssen et al. 2538 (MO, TAN). — Idem, Main Crest Trail, 17°55’54’’S, 49°12’12’’E, 300-500 m, 7.XI.2004, Janssen et al. 2539 (MO, P, TAN), 2552 (P). — Nonokambo, 17°45’S, 48°45’E, 18.VIII.1937, Jardin Botanique 2690 (P). — Varahina, 17°46’S, 48°48’E, 19.VIII.1937, Jardin Botanique 3002 (P). — RN Betampona, 17°55’S, 49°13’E, 450 m, 16.XII.1938, Lam & Meeuse 5987 (K, P). — Toamasina, W of Vavatenina, RNI Zahamena, 17°44’S, 49°00’E, 500-750 m, IX.1993, Malcomber et al. 2520 (P). — Antsiranana, trail to the summit of Marojejy Est, NW of Mandena, 14°26’S, 49°46’E, 600-660 m, 6.X.1988, Miller et al. 3395 (P). — Idem, 14°26’S, 49°46’E, 600-700 m, 12.II.1989, Miller et al. 4029 (P). — Environs de la baie d’Antongil, X.1912, Perrier de la Bâthie 7987 (BM, P). — Betampona, près d’Ambodiriana, 17°55’S, 49°13’E, XII.1925, Perrier de la Bâthie 17475 (BM, P). — Moramanga, forêt d’Ambatovy, 18°49’S, 48°18’E, Rakotomalaza 1600 (P), 1628 (P). — Antananarivo, forêt d’Anjozorobe, 18°24’S, 47°53’E, 23.IV.1988, Rakotondrainibe 717 (P). — Antsiranana, RS d’Anjanaharibe-Sud, Befingotra, 14°45’18’’S, 49°30’18’’E, 870 m, 19.X.1994, Rakotondrainibe et al. 2079 (K, MO, P, TAN). — RNI du Marojejy, Manantenina, 14°26’S, 49°45’42’’E, 760 m, 15.X.1996, Rakotondrainibe 3373 (P, TAN). — Idem, 800 m, 15.X.1996, Rakotondrainibe 3379 (P). — Forêt de Betaolana, Ambodiangezoka, 14°32’18’’S, 49°26’18’’E, 800-950 m, 8.X.1999, Rakotondrainibe et al. 4852 (P, TAN). — Idem, 950 m, 14.X.1999, Rakotondrainibe et al. 4923 (P). — Anjanaharibe-Sud, forêt d’Analabe, Befingotra, 14°46’S, 49°26’30’’E, 1200-1220 m, 26.X.1999, Rakotondrainibe et al. 5053 (P,TAN). — PN de Marojejy, Doany, 14°25’36’’S, 49°36’30’’E, 800-820 m, 14.X.2001, Rakotondrainibe et al. 6230 (K, P, TAN). — Idem, 500- 600 m, 20.X.2001, Rakotondrainibe et al. 6317 (P). — Andapa, Anjialavabe, forêt de Tsaralanto, 14°14’10’’S, 49°23’02’’E, 1138 m, 27.II.2006, Rakotovao et al. 2756 (MO, P, TAN). — Toamasina, Ambatondrazaka, Androrangabe, 17°45’S, 48°43’E, 900 m, 22.IX.2002, Rasolohery 748 (MO, P). — Maroantsetra, massif of Ankirindro, 15°18’27’’S, 49°33’08’’E, 320 m, 1.II.1999, Schatz et al. 3910 (P).

FIELD OBSERVATIONS. — Trunk: HT up to 7 m, DT 5-7 cm, dead petioles persistent as a rudiment, but soon caducous and the leaf scars exposed; surface of young trunks smooth, orange to brown, with very distant leaf scars; surface of older trunks greyish brown, with less distant leaf scars, older trunks usually thinner (sic) than young trunks.

Petiole: with several irregular rows of brown aerophores on either side; petiole bases straight, not arched or sigmoid.

Leaf scars: 2-2.5 × 3.5(-6) cm, obovate to rounded, slightly raised, with up to 5 short, conical, caducous spines on their lower rim, several shallow orifices on the trunk surface below each scar, spirally arranged.

Crown: leaves of young plants with very long, arching petioles and rachises, spreading and supported by the surrounding vegetation; crown of adult plants smaller, more or less umbrella-shaped.

Trunk apex: green, smooth; shiny black scales usually confined to the young croziers; apex often much raised above the point of insertion of the uppermost petiole and well visible through the much spaced petioles.

Lamina: elliptic to ovate, lamina apex often caudate; LL (120-) 200-280 cm, WL 100-150 cm, FW 70-130 cm, NP 11-15.

DESCRIPTION

Petiole: (20-) 50-70 cm long, 1.5-2 cm in diameter; green, violaceous brown below; in some specimens 1-5 much reduced and less deeply dissected pinnae inserted in the lower two thirds of the petiole.

Lamina: bipinnate, very coriaceous, dull light green below, shiny dark green above, lamina base shortly attenuate to truncate, basal pinnae patent and more or less conduplicate; rachis green.

Largest pinnae: 50-80 cm long, distant by 15- 28 cm, adjacent pinnae contiguous to overlapping; their apex triangular to hastate, more or less strongly pinnatifid, frequently with only 2 or 3 segments; abrupt transition from the pinna apex to the petiolulate lateral pinnules; costae and costulae green; a very conspicuous aerophore at the base of each costa.

Largest pinnules: (7-)8-12(-14) × (1.1-) 1.5- 2.2 cm, spaced by less than to more than their width, petiolulate with a distinct petiolule 0.3- 0.6 cm, narrowly ovate-oblong, margin subentire to erose, more or less undulate, serrulate near the pinnule apex, base rounded, slightly asymmetric, apex acute to very shortly caudate; veins twice furcate.

Scales and hairs: scales of the petiole base very caducous, densely imbricate in young leaves, shortly triangular, 1-1.7 × 0.2-0.4 cm, straight, shiny dark brown to black, with a relatively broad, lighter and erose margin, appressed, coriaceous; scattered brown, contorted, antrorse, multicellular hairs on the adaxial face of the costae, sometimes very sparse and short; leaf otherwise glabrous.

Sori: subcostular, contiguous, about 0.2-0.3 cm in diameter, covering entire pinnules or restricted to their lower half; indusia globular, dull brown, coriaceous at least in their lower half, at maturity dehiscing in 3 or 4 lobes or irregularly, but usually not down to their base; receptacle capitate to disciform, much shorter than the rim of mature indusia, paraphyses inconspicuous.

DISTRIBUTION

Northern and Central Madagascar; endemic.

ECOLOGY

(300-) 500-1200 m. Dense evergreen rainforests.

REMARKS

A very characteristic species even in fragmentary herbarium collections due to the size and shape of its pinnae and pinnules and easily identified in the field by its peculiar habit.

Young plants have very large leaves with comparatively soft petioles and rachises supported by the surrounding vegetation. Th eir leaves are up to 5.2 m long, the petiole up to 2.5 m and their pinnules are bigger than those of adult plants. Also, young plants have more vividly orange-brown coloured trunks.

TYPIFICATION AND SYNONYMY

Two sheets of Humblot 278 exist at K. Only one of them carries the species name in Baker’s hand and is here considered to represent the holotype. The fragmentary holotype cannot be confounded with

any other taxon from the Western Indian Ocean making epitypification superfluous.

19. Cyathea tsaratananensis C.Chr. ( Figs 18 ; 46I ; 49C )

Index Filicum Supplementum Tertium 64 (1934), nom. nov. — Cyathea subincisa C.Chr. , in Perrier, Catalogue des plantes de Madagascar, Ptéridophytes: 22 (1931), nom. nud.; Christensen, Dansk Botanisk Arkiv 7: 27, pl. 5 figs 20-22 (1932), nom. illeg. non Cyathea subincisa (Kunze) Domin , Pteridophyta: 264 (1929); Tardieu in Humbert, Flore de Madagascar et des Comores, IVe famille, Cyathéacées : 19 (1951). — Alsophila tsaratananensis (C.Chr.) R.M.Tryon, Contributions from the Gray Herbarium 200: 31 (1970). — Type: Madagascar, massif du Tsaratanana, 1700 m, I.1923, Perrier de la Bâthie 15286 (holo-, P! [P00389621]; iso-, P! [3 sheets], TAN! [2 sheets]).

ADDITIONAL MATERIAL EXAMINED. — Madagascar. Forêt d’Ambatosoratra, 14°46’S, 48°52’E, 8.I.1949, Cours 3363 (P). — Anjanaharibe , 14°42’30’’S, 49°27’30’’E, 1600- 1700 m, 19.XII.1950, Cours 3768 (P). — Idem , 1700 m, 24.XII.1950, Cours 3850 (P). — Vallée de la Lokoho , près d’Ambalavoniho , 14°34’S, 49°44’E, 75-300 m, I.1949, Humbert et al. 22819 (P). — Antsiranana, Montagne d’Ambre , Grand Lac , 12°35’48’’S, 49°09’34’’E, 1300- 1450 m, 8.X.2004, Janssen et al. 2446 ( MO, P, TAN), 2456 (P, TAN) . — Idem , entre Grand Lac et Lac Maudit, 12°35’48’’S, 49°09’34’’E, 1300 m, 9.X.2004, Janssen et al. 2463 ( MO, P, TAN).— Antsiranana, Montagne d’Ambre, entre Lac Maudit et Grand Lac, 12°31’S, 49°09’E, 1350 m, 29.III.1992, Rakotondrainibe 1662 (P). — Andapa, RS d’Anjanaharibe-Sud, Befingotra, 14°44’30’’S, 49°26’30’’E, 1550 m, 15.XI.1994, Rakotondrainibe et al. 2414 (K, MO, P, TAN). — Anjanaharibe-Sud, forêt d’Analabe, Befingotra, 14°45’54’’S, 49°25’55’’E, 1600 m, 4.XI.1999, Rakotondrainibe et al. 5159 (P, TAN) . — Idem, 1660- 1680 m, 6.XI.1999, Rakotondrainibe et al. 5181 ( MO, P, TAN). — Idem, 1600 m, 8.XI.1999, Rakotondrainibe et al. 5194 (P, TAN) .

FIELD OBSERVATIONS. — Trunk: HT up to 4(-7) m, DT (9-) 10-15 cm, dead petioles caducous or only a rudiment persistent and leaf scars usually exposed; trunk surface brown to black, tuberculate with dense squaminate spines.

Petiole: with white, distant aerophores on either side; petiole bases shortly sigmoid.

Leaf scars: 2.5-4 × 2.5-5 cm, rounded and distally emarginate to elliptic, concave, lower margin somewhat raised, contiguous to spaced, with up to 5 big and deep orifices on their lower rim; spirally arranged.

Crown: more or less umbrella-shaped, petioles straight.

Trunk apex: densely scaly, brown to black, usually concealed by the petiole bases.

Lamina: elliptic to ovate; LL 145-200 cm, WL 70- 90 cm, FW 60-90 cm, NP 18-26.

DESCRIPTION

Petiole: 20-50 cm long, 2.5-3.5 cm in diameter; brown to castaneous, sometimes violaceous brown.

Lamina: bipinnate, herbaceous (not coriaceous), pale green to slightly glaucous below, dull to shiny green above, lamina base shortly attenuate, basal pinnae patent to reflexed and conduplicate; rachis of the same colour as the petiole, but often more pronouncedly reddish, sometimes green.

Largest pinnae: 45-60 cm long, distant by 6-7 cm, adjacent pinnae contiguous to overlapping, their apex acute to shortly caudate, pinnatifid; costae and costulae of the same colour as the rachis.

Largest pinnules: 5-7 × 0.9-1.2 cm, spaced by less than their width, shortly petiolulate, triangularoblong, their apical half slightly falciform, margin deeply crenate up to halfway down to the costula, more shallowly crenate in fertile parts of the pinnule, undulate, apex acute to caudate, more or less sharply serrate, base truncate to subcordate, more or less pronouncedly biauriculate; veins 2 to 4 times furcate, pinnate in larger lobes.

Scales and hairs: scales present from the petiole base upwards to 40 cm on the petiole, spaced, i.e. not overlapping, persistent, dull dark brown to shiny black, abaxial scales conical to pyramidal, 0.3-0.5 × 0.2-0.3 cm, straight, patent, not antrorse, strongly indurated, transforming into blunt warts further up on the petiole, adaxial scales narrowly triangular to deltoid, up to 0.7 cm long, slightly crispate, patent or appressed, coriaceous; dense multicellular, more or less antrorse, brown to stramineous, more or less crispate hairs on the adaxial face of the costae; scattered, caducous, dull brown filiform scales and sparse hairs on the adaxial face of the rachis; leaf otherwise glabrous.

Sori: subcostular, spaced by less than to more than their width, 0.1-0.2 cm in diameter, covering the pinnules in their lower half, rarely covering the entire pinnule; indusia globular, brown, subcoria- ceous, at maturity dehiscing in 2-4 lobes; receptacle capitate, shorter than the rim of mature indusia, paraphyses inconspicuous.

DISTRIBUTION

Northern Madagascar: Montagne d’Ambre, Anjanaharibe, Marojejy; endemic.

ECOLOGY

(100-) 1300-1700 m. Dense evergreen rainforest, on slopes and crests.

REMARKS

Cyathea ligulata has similar, but usually bigger, petiole scales. It can be easily distinguished from the present taxon by its prominent indument of scales and hairs on the abaxial face of the costae and costulae as well as by its smaller pinnules.

Rakotondrainibe 5159 has particularly small, subentire pinnules up to 3 × 0.6 cm with an obtuse apex and close standing sori, but perfectly agrees with C. tsaratananensis in all other characters.

TYPIFICATION AND SYNONYMY

Four sheets of Perrier de la Bâthie 15286 are present at P. A label “ Cyathea subincisa n. sp. C.Chr. Original” in Christensen’s hand is glued to one sheet and although the most fragmentary, this sheet must be considered the holotype of the species. Together with the isotypes, which should not be dissociated from the holotype specimen, the original material can be unambiguously distinguished from all other Madagascan species making epitypification superfluous.

Figures

FIG. 1. — Spores of Cyathea sect. Alsophila in Madagascar and on the Comoros: A-C, spores of taxa belonging to the bipinnate clade (Janssen et al. 2008) have a perispore formed by dense slender rodlets; D-F, spores of taxa belonging to the tripinnate clade (Janssen et al. 2008) have a perispore with prominent crests; A, C. approximata Bonap.; B, C. kirkii Hook.; C, C. serratifolia Baker; D, C. boivinii Mett.ex Kuhn var.boivinii; E, C. melleri (Baker) Domin;F, C. similis C.Chr.,a young spore with a distantly verrucose perispore (Janssen & Rakotondrainibe 2006; Gastony & Tryon 1976). A, Janssen et al. 2449 (P); B, Rakotondrainibe et al. 6751 (P); C, Rakotondrainibe et al. 6230 (P); D, Janssen et al. 2481 (P); E, Janssen et al. 2536 (P); F, Janssen et al. 2576 (P). Scale bars: 10 μm.

FIG. 17. — Cyathea serratifolia Baker: A, scale from the base of the petiole; B, habit (left: old plant, short and close standing petioles; right:young plant,long and distant petioles);C, leaf scars and trunk surface;D, pinnules abaxially with a fragment of the costa; E, pinna abaxially with a fragment of the rachis, sori only partly indicated. A, D, E, Janssen et al. 2537 (P); B, uncollected, photographs at P; C, Janssen et al. 2538 (P). Scale bars: A, 0.1 cm; B, 1 m; C, E, 5 cm; D, 1 cm.

FIG. 46. — Distribution maps for Cyatheaceae (genus Cyathea) of Madagascar and the Comoros. Species are arranged in alphabetical order.

FIG. 49.— Photographic documentation of field characters in Cyathea: A-E, habit;A’-E’, trunk apex;A”-E”, trunk surface at breast height.A-A”, Cyathea hebes Janssen & Rakotondr.; B-B”, C. serratifolia Baker; C-C”, C. tsaratananensis C.Chr.; D-D”, C. viguieri Tardieu; E-E”, C. approximata Bonap.; E’, left: apex of a form with distant petioles (apical view), right: apex of a form with close standing petioles (lateral view).A-A”,Janssen et al. 2519; B, B”, C,C’,E-E”,uncollected;B’, Janssen et al.2538; C”, Janssen et al. 2446; D-D”, Janssen et al. 2575. Vouchers at P. Photos A-A”, B-B”, C-C”, E, E’ right, E” by G. Rouhan (MNHN); all other photos by T. Janssen. Scale bars: A-E, 1 m; A’-E’, A”-B”, D”, E”, 10 cm; C”, 5 cm.

FIG. 18. — Cyathea tsaratananensis C.Chr.: A, pinnules abaxially with a fragment of the costa, note that the sterile pinnule is more strongly crenate; B, leaf scars and trunk surface, form with close standing petioles; C, habit; D, leaf scars and trunk surface, common form; E, segment from the basal part of the petiole with scales; F, scales from the base of the petiole (left: strongly indurated, pyramidal scale; right: less strongly indurated scale); G, pinna abaxially with a fragment of the rachis, fertile in its lower half only. A, G, Rakotondrainibe et al. 5181 (P); B, Janssen et al. 2456 (P); C-F, Janssen et al. 2446 (P). Scale bars: A, B, D, E, 1 cm; C, 1 m; F, 0.1 cm; G, 5 cm.