Corresponding authors: Vladimir Ječmenica (
Academic editor: L. Peruzzi
Recent field inventories and taxonomic research in Central Africa have resulted in the discovery of many new orchid species. Five specimens of an apparently new
Des travaux récents d’inventaires et de taxonomie ont abouti à la découverte de nombreuses espèces nouvelles d’orchidées en Afrique centrale. Cinq spécimens n’appartenant à aucune espèce d’
Ječmenica V, Droissart V, Noret N, Stévart T (2016) Taxonomy of Atlantic Central African orchids 5. A new species of Angraecumsect.Conchoglossum (Orchidaceae, Angraecinae) from Gabon and Cameroon. PhytoKeys 61: 61–71. doi:
According to the latest count of WCSP (
A revision of
The first collection of the new species originates from Mont Seni in the Monts de Cristal National Park in Gabon (IUCN Category II National Park). This specimen was collected by Nguema Miyono (
This paper is the fifth in a series of publications (
This study was conducted under the framework of the first author’s Master’s thesis. A revision including 109 specimens from all Missouri Botanical Garden Institut de Recherche pour le Développement
A preliminary risk of extinction assessment was made using the IUCN Red List Categories and Criteria ( area of occupancy extent of occurrence
Cameroon. South Region of Cameroon, Campo-Ma’an National Park, nearby villages of Ebianemeyong and Nyabissan,
Small epiphytic herbaceous plant. Stem hanging, slightly zig-zag in form, unbranched, up to 8.5 cm long. Leaves alternate, spaced, narrowly ovate to lanceolate, sometimes slightly falcate and always convolute in the distal part, margins entire; distinct midvein forming slight channel, accompanied with 2 or 3 nerves on each side merging into one throughout; small stomata spots visible in young leaves; leaf apex unequally bilobed, acuminate, with the larger lobe 1.5–2.8 mm long and the smaller 0.3–1.2 mm long, leaf blade 2.3–4.1 × 0.6–0.9 cm; leaf internode about 5–6 mm long. Inflorescence single flowered, eventually two-flowered; peduncle elongated 13–23 mm long, opposite to the leaf at the node. Bracts acute, 2 mm long. Flowers white, opening diameter about 12.5 mm. Ovary and pedicel not resupinate, 8 mm long. Dorsal sepal 6.2–8.5 × 3 mm, elliptic, acute, thick, with entire margins. Lateral sepals 6–7 × 2–2.2 mm, elliptic, acute, thick, with entire margins. Petals 5–6.5 × 2–2.2 mm, obliquely elliptic, acute, entire margins, similar in shape to lateral sepals. Lip 5–6 × 4.5–5 mm, concave, rhombic when flattened, widest between first third and the half, acute; spur 16–19.5 mm, cylindric, slender, straight, somewhat elliptically inflated and greenish at the apex. Column 1.5 × 2 mm. Pollinia 2,
Photographs of living specimen of
Gabon. Monts de Cristal National Park. Mont Seni, 13 Sept 2001,
Endemic to the Lower Guinea Domain (Cameroon and Gabon, Fig.
Distribution of
Flowering occurs in June and September.
IUCN Red List category: Least Concern
The specific epithet of the new species owes to the particular leaf shape. Even though there are several interpretations of “lanceolate” shape according to different authors (Linnaeus, Lindley), we relied on the current depiction from
1a | Leaves oblong; spur sigmoid, apex not or rarely slightly cylindrically inflated |
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1b | Leaves not oblong; spur straight or slightly curved, apex inflated |
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2a | Leaves broadly ovate; spur apex circularly inflated |
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2b | Leaves narrowly ovate, lanceolate or elliptic; spur elliptically inflated |
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3a | Leaves very fleshy, broadly elliptic, up to 2.7 cm long; lip elliptic to ovate |
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3b | Leaves thin, narrowly ovate to lanceolate, distally convolute up to 4.1 cm long; lip rhombic |
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The diagnostic characters of species from Central African region that belong to the section
Morphological comparison of characters for seven related continental African
Taxa | Distribution | Stem size | Leaves | Peduncle | Sepals | Petals | Lip | Spur |
---|---|---|---|---|---|---|---|---|
Democratic Republic of the Congo, Tanzania, Malawi, Zambia | 15.5–40 cm | 5.6–8 × 0.5–0.9 cm |
1.3–2.2 cm | Elliptic, |
Elliptic, acuminate, |
Straight or slightly curved, elliptic apical inflation, |
||
Nigeria, Cameroon, Gabon | 10–22cm | 2.7–4 × 1.5–1.9 cm |
2–4 cm | Elliptic, |
Elliptic to ovate, acute, 7–11 × 2.5–4.5 mm | Bent upwards with |
||
Ivory Coast, Nigeria | 8–11 cm | 7–11 × 1–2.2 cm narrowly elliptic, |
2–4 cm | Elliptic, |
Straight with elliptic apical inflation, |
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Nigeria, Cameroon, Equatorial Guinea | 7.5–11 cm | 1.7–2.65 × 0.7–1.1 cm elliptic, |
0.7–1.8 cm | Elliptic, |
Elliptic, acute 7.5–9.5 × 1–2.2 mm | Elliptic to ovate, acuminate 6.5–8.5 × 4 mm | Straight with elliptic apical inflation, |
|
Kenya, Tanzania, Malawi, Mozambic, Zambia, Zimbabwe, KwaZulu-Natal | 8–15 cm | 3.7–6 × 0.4–0.8 cm |
1.5–3 cm | Elliptic, |
Elliptic, acuminate, |
Straight, |
||
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Cameroon, Gabon | Up to 8.5 cm | 2.3–4.1 × 0.6–0.9 cm |
1.3–2.3 cm | Elliptic, |
Irregularly straight with elliptic apical inflation, |
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Ghana, Republic of Guinea, Ivory Coast, Liberia, Nigeria, Togo, Central African Republic, Cameroon, Republic of the Congo, Gabon, Gulf of Guinea Islands, Rwanda, Democratic Republic of the Congo, Tanzania, Uganda | 6–15 cm | 4.2–9.2 × 0.7–1 cm |
0.6–3.5 cm | Elliptic, |
Obliquely linear to elliptic, |
Elliptic to slightly ovate, |
Floral morphology, particularly the lip shape of new species is similar to
The novelty is a representative of
We express our gratitude to the curators of several herbaria (