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This species is accepted, and its native range is W. Tropical Africa.

[KBu]

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

Type
Guinea, Fouta-Djallon, Dalaba, Sept. 1954, Schnell 6825 (K!, holotypus).
Morphology General Habit
Plants terrestrial
Vegetative Multiplication Rhizomes
Rhizome short-decumbent, up to 75 mm long, up to 6 mm in diameter, closely set with roots, persistent stipe bases and scales, the scales up to 9 x 2 mm, dull ferrugineous, thinly chartaceous, sessile, broadly attached, narrowly triangular, narrowly ovate to filiform, narrowly to broadly cuneate, irregularly denticulate, with scattered capitate glands along the margin, or with scattered glands and long, pluricellular filiform outgrowths of which the apex terminates in several oblong thin-walled cells, the scale apex terminates in a short series of oblong cells, up to 9 x 2.4 mm, the scales regularly with one or more pluricellular filiform outgrowths from the base
Morphology Leaves
Fronds crowded, arching, up to 950 mm long
Morphology Leaves Stipes
Stipe stramineous, proximally adaxially flattened, sulcate higher up, up to 380 mm long, up to 4 mm in diameter, proximally densely scaled, sparsely scaled higher up, the scales up to 10 x 2.4 mm, similar to those on the rhizome, the smaller scales simple or with a filiform pluricellular outgrowth from the base
Morphology Leaves Leaf lamina
Lamina narrowly ovate, up to 570 x 325 mm, to 2- pinnate-pinnatifid, with up to 12 petiolated pinna pairs, distally the pinnae become sessile and eventually adnate and increasingly basiscopically decurrent
Morphology Leaves Rachis
Rachis stramineous, adaxially shallowly sulcate, narrowly winged near the apex, sparsely scaled, the scales fugaceous, up to 6 x 1.2 mm, stramineous, thinly chartaceous, sessile, narrowly lanceolate to filiform, cuneate, often glandular at the base, or with a pluricellular filiform outgrowth at the base, irregularly set with short or long, filiform, pluricellular outgrowths of which the apex terminates in an oblong or subglobose cell, the scale apex terminates in a short uniseriate series of oblong cells, smaller scales often short-stalked, simple or with a filiform pluricellular outgrowth from the base
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, up to 1-pinnate-pinnatifid, basal pinna up to 168 x 80 mm, basal pinna pair basiscopically developed, inaequilaterally narrowly triangular to lanceolate, oblong acuminate to linear acuminate towards the lamina apex, with up to 4 stalked pinna pairs Rachis stramineous, narrowly winged for most of the length, adaxially shallowly sulcate, sparsely set with filiform scales, abaxially sparsely scaled, the scales up to 2.5 x 0.3 mm, stramineous to ferrugineous, chartaceous, sessile or short-stalked, lanceolate to subulate, eglandular or with a few capitate glands along the margin, regularly with one or more pluricellular, uniseriate filiform outgrowths from near the base, the apex terminates in a short uniseriate series of cells of which the apical cell varies from oblong or subglobose
Morphology Leaves Pinnules
Pinnules stalked, the stalk up to 3 mm long, near opposite to alternate, proximally widely spaced, more closely spaced distally, herbaceous, proximally pinnatifid, progressively more shallowly lobed distally, basiscopic pinnule on basal pinna up to 50 x 24 mm, narrowly ovate to oblong-acuminate, acroscopic pinnule on basal pinna up to 28 x 19 mm, ovate to oblong- acuminate
Morphology General
Costa shallowly sulcate adaxially, glabrous to sparsely set with filiform scales, abaxially sparsely scaled, the scales up to 2.5 x 0.8 mm, stramineous, chartaceous, sessile, ovate to subulate, the margins irregularly set with a few short pluricellular outgrowths, the apex terminates in a short uniseriate series of thin-walled cells Segments sessile, up to 14 x 8 mm, broadly ovate, lobes up to 8 x 4 mm, oblong- obtuse to oblong-truncate, shallowly dentate, adaxially glabrous or sparsely set with clavate glands and 4 to 6- celled moniliform hairs along the veins, abaxially sparsely set with clavate glands (56 -)77(- 92) μm long along the veins, and 4 to 8-celled moniliform hairs up to 340 μm long along and near the veins, the hairs rarely with a glandular cell near the base Stomata mostly of the polocytic type, (48 -)55(- 64) μm long
Morphology Leaves Leaf veins
Venation anadromous, catadromous towards the apex, immersed adaxially, evident abaxially, ending in the teeth near the margin
Morphology Reproductive morphology Sori
Sori essentially 2-seriate on the pinnules, 2-seriate on the segments in larger specimens, discrete at maturity, inframedial on essentially the anadromous vein branches
Morphology Reproductive morphology Sori Indusium
Indusium ferrugineous, firmly herbaceous, up to 1.6 mm in diameter, reniform, entire to strongly repand, eglandular
Morphology Reproductive morphology Sporangia
Sporangium stalk simple, glandular, or haired, capsule with (10 -)12(- 14) indurated annulus cells, epistomium (3 -)4(- 5)-celled, hypostomium (3 -)4(- 5)-celled
Morphology Reproductive morphology Spores
Spores brown, 64 per sporangium, monolete, plano-convex, perispore smooth, forming tall but narrow reticulate ridges, exospore (38 -)40(- 46) x (24 -)27(- 30) μm.
Ecology
Dryopteris occidentalis is a forest species, in mountainous plateau regions with an average altitude of 940 m
Distribution
Appears to be widespread in the mountainous regions of West Africa.

Native to:

Guinea, Ivory Coast, Nigeria

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

First published in Kew Bull. 59: 214 (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.

Literature

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 http://www.ipni.org and http://apps.kew.org/wcsp/
© Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

Kew Bulletin
Kew Bulletin
http://creativecommons.org/licenses/by-nc-sa/3.0

Kew Names and Taxonomic Backbone
The International Plant Names Index and World Checklist of Selected Plant Families 2021. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
© Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0