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This species is accepted, and its native range is Sierra Leone.


Roux, J. (2004). Three New Species of Dryopteris (Pteropsida: Dryopteridaceae) from West Africa. Kew Bulletin, 59(2), 207-217. doi:10.2307/4115851

Sierra Leone, Sugar Loaf mountain, on ground amongst rocks, 730 m, 15 Oct. 1951, T S. Jones 339 (BM!, holotypus).
Morphology General Habit
Plants terrestrial, epilithic or (rarely) epiphytic. Rhizome suberect to short-decumbent, up to 10 mm in diameter, closely set with roots, persistent stipe bases and scales, the scales up to 18 x 2 mm, ferrugineous, matt, chartaceous, subulate to linear- acuminate, truncate to cordate, mostly with several pluricellular, pluriseriate or uniseriate marginal outgrowths on the lower part, proximally often also with a few scattered capitate glands along the margin, entire to irregularly denticulate towards the apex, the apex flagelliform, terminating in a uniseriate series of thin-walled cells
Morphology Leaves
Fronds crowded, suberect to arching, up to 640 mm long
Morphology Leaves Stipes
Stipe proximally castaneous, brown higher up, proximally adaxially flattened, shallowly sulcate higher up, up to 395 x 5 mm in diameter, proximally densely scaled, sparsely scaled higher up, the scales similar to those on the rhizome, but slightly smaller and mostly with more marginal outgrowths
Morphology Leaves Leaf lamina
Lamina lanceolate to ovate, up to 445 x 255 mm, to 2- pinnate-pinnatifid, with up to 11 petiolated pinna pairs, distally the pinnae become sessile and eventually adnate and increasingly basiscopically decurrent
Morphology Leaves Rachis
Rachis brown to stramineous, adaxially shallowly sulcate, narrowly winged near the apex, sparsely to moderately scaled, the scales up to 3.5 x 0.5 mm, ferrugineous, chartaceous, sessile, filiform to lanceolate, ctineate, entire to irregularly set with capitate glands and pluricellular hairs which mostly originate along the basal margin of the scale, capitate glands may also occur on the marginal hairs, the apex terminates in a short series of thin- walled cells
Morphology Leaves Pinnae
Pinnae stalked, the stalk up to 10 mm long, proximally spaced to slightly overlapping, near opposite to alternate, the basal pinna pair longest or slightly shorter than the pinna pair above, to 1- pinnate-pinnatifid, basal pinnae up to 175 x 76 mm, basiscopically developed, inaequilaterally narrowly triangular, pinnae higher up symmetric or not conspicuously basiscopically developed, narrowly triangular to oblong-acuminate, with up to 6 stalked pinnule pairs Rachis brown to stramineous, adaxially shallowly sulcate, narrowly winged towards the apex, sparsely to moderately set with clavate glands, adaxially sparsely set with filiform scales, abaxially moderately scaled, the scales similar to, but smaller than those on the rachis
Morphology Leaves Pinnules
Pinnules stalked, stalk up to 2 mm long, proximally widely spaced, more closely spaced distally, firmly herbaceous, proximally pinnatifid, lobed towards the apex, basiscopic pinnule on the basal pinna up to 58 x 17 mm, acroscopic pinnule on the basal pinnae up to 35 x 14 mm, narrowly triangular, ovate, or oblong-acute
Morphology General
Costa shallowly sulcate adaxially, sparsely set with clavate glands and filiform scales, abaxially variously set with clavate glands and filiform scales Segments sessile, up to 8 x 5 mm, broadly ovate-obtuse, shallowly dentate, adaxially glabrous or sparsely set with clavate glands along and between veins, abaxially sparsely set with clavate glands (60 -)88(- 130) μm long along the veins, and with isocytic hairs up to 236 μm long along and near the veins Stomata mostly of the polocytic type, (42 -)53(- 66) μm long
Morphology Leaves Leaf veins
Venation anadromous, catadromous towards the apex, adaxially immersed, evident abaxially, ending in the teeth near the margin
Morphology Reproductive morphology Sori
Sori essentially 2-seriate on each pinnule, medial to inframedial, more or less restricted to the anadromous vein branch of each segment or lobe, to 1.2 mm in diameter
Morphology Reproductive morphology Sori Indusium
Indusium castaneous, firmly herbaceous, to 1 mm in diameter, reniform, repand, glabrous or glandular along the margin, rarely also haired, often glandular on the surface
Morphology Reproductive morphology Sporangia
Sporangium stalk set with one or more large capitate glands and/or haired, capsule with (11 -) 13 (- 18) indurated annulus cells, epistomium (3 -)4(- 6)- celled, hypostomium (4 -)5(- 7)-celled
Morphology Reproductive morphology Spores
Spores brown, 64 per sporangium, monolete, plano-convex, perispore smooth, with short and low wings and bulges, exospore up to (34 -)38(- 46) x (24-)28(- 34) μm.
Dryopteris amblyodonta appears to be restricted to the Loma and Tingi mountains in eastern Sierra Leone.
In the Loma mountains the species occurs from 610 to 1700 m. At Bin tumani (Loma Mansa), the highest part of the mountains, it grows among doleritic rocks and on cliff faces, but it has also been recorded as as an epiphyte in dense shade along streams. In the Tingi mountains, slightly southeast of the Lonma mountains, it has been recorded at an altitude of 1825 m, growing among rocks.
Tardieu-Blot et al. (1971) list several Dryopteris collections from the Loma mountains, but they clearly did not recognize collections of D. amblyodonta as representing an undescribed species and ascribed them to D. pentheri (Krasser) C. Chr. Dryopteris amblyodonta differs from D. pentheri in having fronds up to 640 mm long, whereas that of D. pentheri can be up to 1.8 m long. In D. amblyodonta the longer stipe in relation to lamina length (1:1.1) is also more apparent than in D. pentheri where the ratio is 1:1.6. Capitate lamina glands are 60 to 130 μm long, whereas those in D. pentheri are oblong and range between 60 and 260 μm. Two-celled hairs occurring along the lamina axes of D. pentheri do not occur in D. amblyodonta. The indusia often bear glands along the margin and surface but rarely they also have pluricellular uniseriate hairs along the margin. In D. pentheri the indusia are eglandular. The sporangium stalk has several large capitate glands and hairs. The sporangium stalk of D. pentheri is hairless, haired or glandular. If glandular, then a single clavate gland generally occurs on the stalk. These species also differ in exospore size with that of D. amblyodonta being slightly smaller (34 -)38(- 46) x (24 -)28(- 34) μm than that of D. pentheri, (38 -)45(- 60) x (27 -)31 (- 40) μm. The specific epithet is derived from the blunt pinnule teeth.

Native to:

Sierra Leone

Dryopteris amblyodonta J.P.Roux appears in other Kew resources:

First published in Kew Bull. 59: 207 (2004)

Accepted by

  • Roskov Y. & al. (eds.) (2018). World Ferns: Checklist of Ferns and Lycophytes of the World Species 2000 & ITIS Catalogue of Life Naturalis, Leiden, the Netherlands.


Kew Bulletin

  • Roux, J. P. (2000). The genus Polystichum (Dryopteridaceae) in Africa. Bull. Nat. Hist. Mus. London (Bot.) 30: 33-79.
  • Holmgren, P. K., Holmgren, N. H. & Barnett, L. C. (eds.) (1990). Index Herbariorum. Part 1. The herbaria of the world, 8th edn. Regnum Veg. 120: 1 - 693.
  • Fraser-Jenkins, C. R. (1986). A classification of the genus Dryopleris (Pteridophyta: Dryopteridaceae). Bull. Brit. Mus. (Nat. Hist.), Bot. 14: 183-218.
  • Gibby, M., Jermy, A. C., Rasbach, H., Rasbach, K., Reichstein, T. & Vida, G. (1977). The genus Dryopteris in the Canary Islands and Azores and the description of two new tetraploid species. Bot. J. Linn. Soc. 74: 251 - 277.
  • Lovis, J. D. (1977). Evolutionary patterns and processes in ferns. Advances Bot. Res. 4: 229 - 415.
  • Widén, C.-L., Lounasmaa, M., Vida, G. & Reichstein, T. (1975). Die Phloroglucide von drei Dryopteris- Arten van den Azoren sowie zwei Arten von Madeira und den Kanarischen Inseln zum Vergleich. Helv. Chim. Acta 58: 880 - 904.
  • --- Jaeger, P. & Adam, J. G. (1971). Le massif des Monts Loma. V. Pteridophytes Filicales. Mém. Inst. Fondam. Afrique Noire 86: 114 - 177.
  • Wagner, W. H. (1971). Evolution of Dryopteris in relation to the Appalachians. In: P. C. Holt (ed.), The distributional history of the biota of the southern Appalachians. Part II, Flora. Research Division Monograph 2: 147-191. Virginia Polytechnic Institute and State University, Blacksburg, Virginia.
  • Alston, A. H. G. (1959). The ferns and fern allies of West tropical Africa (Supplement to the flora of West Africa, 2nd edn, London). Crown Agents for Overseas Governments and Administrations, London.
  • --- (1953). Les pteridophytes de l'Afrique intertropicale Française. Mém. Inst. Franç. Afrique Noire 28: 1 -241.
  • --- & Des Abbayes, H. (1951). In: H. Des Abbayes, A. H. G. Alston & M. L. Tardieu-Blot, Contribution à la flore des Pteridophytes d'A.O.F. (Guinée et Côte d'Ivoire). Bull. Inst. Franç. Afrique Noire 13: 79 - 86.
  • Tardieu-Blot, M. L. (1943). Fougères de Guinée. Bull. Soc. Bot. France 90: 94- 97, 116- 118.
  • Jeanpert, M. E. (1910). Fougères récoltées par M. Pobéguin au Fouta-Djallon (Côte occidentale d'Afrique). Bull. Mus. Natl. Hist. Nat. 7: 403 - 404.

Kew Backbone Distributions
The International Plant Names Index and World Checklist of Selected Plant Families 2021. Published on the Internet at and
© Copyright 2017 World Checklist of Selected Plant Families.

Kew Bulletin
Kew Bulletin

Kew Names and Taxonomic Backbone
The International Plant Names Index and World Checklist of Selected Plant Families 2021. Published on the Internet at and
© Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families.