Dendrobium oppositifolium N. Halle
Creators: name: Pignal, Marc
name: Laudereau, Christian
name: Gâteblé, Gildas
name: Laudereau, Pierre-Louis
Publisher: name: Zenodo
Year: 2022
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Asparagales
Orchidaceae
Dendrobium
Dendrobium oppositifolium

description: Dendrobium oppositifolium (Kraenzl.) N.Hallé
(Figs 2E; 3 F-J; 4)
Flore de la Nouvelle-Calédonie & Dépendances 8: 119 (Hallé 1977). — Eria oppositifolia Kraenzl., Vierteljahrsschrift der Naturforschenden Gesellschaft in Zürich 74: 90 (Kränzlin 1929). — Tetrodon oppositifolius (Kraenzl.) M.A.Clem.& D.L.Jones, Orchadian 12: 310 (Clements & Jones 1998).
— Type: New Caledonia. Auf den Araucarien auf dem Plateau des Koniambo, Koné, [on the Araucaria on the Plateau de Koniambo], fl., 18.I.1925, A.U. Däniker 894 (holo-, Z [Z-000016413], image seen).
Dendrobium multilobatum Guillaumin, Mémoires du Muséum national d’Histoire naturelle, série B, Botanique 8: 36 (1957). —
Type: New Caledonia. Bord de forêt de montagne près de la côte, 500 m de la route de la Mgne [Montagne] des Sources, fl., 29.XII.1950, Hürlimann 468 (holo-, Z [Z-000016357], image seen; iso-, P [P00121211!] fragment).
ETYMOLOGY. — The epithet refers to the leaves which are opposite.
PHENOLOGY. — The species flowers mainly during the hottest season between October and March but from herbarium specimens, flowering has also been observed in July. Fruits have been recorded all the year (based on herbaria and field observations).
ECOLOGY. — This species lives as an epiphyte on trees, usually in rainforests, forest edges and sometimes in more open vegetation conditions (Araucaria spp.) at higher altitudes. Most of the observations and specimens are from open or low forests ranging from 200 to 1200 m above sea level. Because Dendrobium oppositifolium seems to favour semi-shaded conditions, it has been rarely observed in dense rainforests where it might occur within the difficult to access canopy of the large and highest trees.
CONSERVATION STATUS. — It is a common endemic species distributed from the South to the North of mainland Grande Terre and even on Île des Pins [Isle of Pines]. Even if some plants and populations are threatened by anthropogenic fires and by illegal removal (the species is protected in the Northern province) from plant and orchid hunters, the species is globally not threatened. It has been successfully cultivated in Paris museum greenhouses as well as by local orchid growers, but remains very difficult to maintain. We agree with the RLA Endemia assessment made on 29 January 2016 (Butin et al. 2020b) classifying the species as Least Concern (LC).
ADDITIONAL MATERIAL EXAMINED. — New Caledonia. Province Nord, Ouégoa, Mandjélia, 780 m, forêt, 4.I.1978, P.R.J. Bamps 6123 (P [P00115105]!). — Kone, Plateau de Kaniambo, Koné, 18.I.1925, A.U. Däniker 894 (P [P02106271] photocopy with an additional drawing of the flower by N. Hallé!). — Ouégoa, Crête au Sud du Col d’Amos, 17.III.1966, H.S. MacKee 14573 (P [P00115093]!). — Hienghène, Massif de Ton-Non: Roches Ouaième, 10.I.1968, H.S. MacKee 18246 (P [P00115091]!). — Pouembout, Mt. Paéoua, 15.II.1968, H.S. MacKee 18427 (P [P00115087]!). — Ouégoa, Haute Diahot: Tendé (Expl. For. Frouin), 500- 660 m, 12.III.1968, H.S. MacKee 20003 (NOU [NOU003683]!; P [P00115086]!). — Ouégoa, Pouébo:Crête entre Mandjélia / Salandané, 15.III.1969, H.S. MacKee 21281 (P [P00115085]!). — Ouégoa, Pouébo: Mandjélia / Salandané, 26.II.1970, H.S. MacKee 21630 (P [P00115083]!). — Poya, Ponérihouen: Contrefort E Mt. Aoupinié, 26.IV.1972, H.S. MacKee 25330 (P [P00115097]!). — Poya, Pente S Mt. Boulinda, 30.VII.1973, H.S. MacKee 27014 (P [P00115080]!). — Pouébo, Pouébo, 24.VII.1974, H.S.MacKee 28970 (P [P00115104]!). — Hienghène, Panié, 12.I.1976, H.S. MacKee 30664 (P [P00115079]!). — Poya, Ponérihouen: Crête sommet Mt. Aouipinié, 10.V.1976, H.S. MacKee 31199 (P [P00115096]!). — Kaala-Gomen, Crête SW Mt. Taom, 13.VII.1979, H.S. MacKee 37144 (P [P00115112]!). — Pouébo, Pouébo: Oumbarinien, 9.I.1981, H.S. MacKee 38553 (P [P00115111]!). — Hienghène, Pente E Mt. Panié, 11.II.1981, H.S. MacKee 38737 (P [P00115110]!). — Houaïlou, Bourail: Mé Jéjéhari, 5.II.1985, H.S. MacKee 42444 (P [P00115114]!). — Mt Colnett: Versant Est, 800 m, forêt humide, Schistes, 2.II.2003, A. Mouly, G. McPherson & U. Svenson 94 (P [P00591695]!). — Poindimié, Massif du Tchingou, face Est, 29.III.2001, J. Munzinger 572 (P [P00239087]!). — Pouembout, Paéoua Mt 800-1100m, 1100 m, forêt à Nothofagus, 26.I.2010, J. Munzinger 6021 (NOU [NOU053561]!). — Hienghène, Dawenia (zone), 929 m, 14.II.2010, J. Munzinger et al. 6319 (NOU [NOU063498]!). — Hienghène, La Guen, cascade (Panié), 910 m, forêt basse, 23.II.2010, J. Munzinger (Leg. Butin, J.- P.) 6468 (NOU [NOU063648]!). — Mt Panié, 500- 900m, 14.II.2006, Y. Pillon 294 (NOU [NOU010843]!). — Mont Panié, forêt basse, 14.II.2006, Y. Pillon, J. Munzinger, I. Spir & al. 9486 (P [P00684671]!). — Kaala-Gomen, Taom Mt (zone), 900 m, 24.III.1982, B. Suprin 1731 (NOU [NOU003688]!). — Tipindjé: Mont Cantaloupaï (versant N), 16.IX.1983, B. Suprin 2295 (P [P00115107]!). — Kouaoua: décharge Montmartre, 750 m, 14.II.1978, J.-M. Veillon 3524 (NOU [NOU003684]!; P [P00115109]!). — Houailou, Mt Menazi, crête vers 900 m versant nord, 6.VII.1989, J.-M. Veillon 7075 (NOU [NOU003685]!). — Wagap, 1861-1867, E. Vieillard 3284 (P [P00115101]!). — Kaala-Gomen, près du sommet du Mont Kaala, 1000 m, 2.I.1943, R. Virot 1402 (P [P00115098]!). — Province Sud: Sarraméa, Mé Améri, 700 m, 29.II.1950, A. Guillaumin 8996 (P [P00115094]!). — Boulouparis, Mt Do (zone), sous-bois de forêt, 16.I.1982, M. Hoff 4423 (NOU [NOU003687]!). — Bordure de forêt de montagne, près de la côte, 500 m de la route pour la Montagne des Sources, 29.III.1950, H. Hürlimann 468 (P [P00121211]!). — Boulouparis, Mont Do, 13.IX.2019, C. Laudereau 269 (NOU [NOU091401]!). — Païta, Dzumac, 13.IX.2019, C. Laudereau 281 (NOU [NOU091400]!). — Yaté, Plateau de la Montagne des Sources, 31.III.1967, H.S. MacKee 18200 (P [P00115092]!). — Bourail, Maoya Mé: contrefort S Djiaouma, 11.II.1970, H.S. MacKee 21554 (P [P00115084]!). — Boulouparis, Plateau sommet Mt. Do, 26.I.1972, H.S. MacKee 24898 (P [P00115082]!). — Bourail, 4 km à l’W Mé Aoui, 14.II.1976, H.S. MacKee 32265 (P [P00115078]!). — Boulouparis, Mt. Do, 22.II.1976, H.S. MacKee 32288 (P [P00115095]!). — Païta, Mt. Mou, 27.V.1979, H.S. MacKee 36940 (P [P00115113]!). — Sarraméa, Col Amieu: Mt. Pembai, 1.III.1982, H.S. MacKee 40302 (P [P00115115]!). — Along old lumber road to top of Mt Mé Ori, above Katrikoin, 900 m, 7.IX.1980, G. McPherson 3054 (P [P00115106]!). — Thio, Mont Nakada, 18.IV.2001, J. Munzinger 801 (P [P00217010]!). — Thio, Forêt de Sailles, 4.III.2001, J. Munzinger 1194 (P [P00239729]!). — Yaté, Massif du Kouakoué, bassin de la Haute Ni, 950 m, 30.IV.2004, M. Pignal, J. Munzinger et P. Lowry 2438 (P [P00465755]!). — Mont Do, c. 900-1000 m, en lisière de forêt, très souvent sur Araucaria laubenfelsii, 1020 m, 1.II.1972, J.-M.Veillon 2511 (NOU [NOU003686, NOU003686]!; P [P00115102, P00115103, P00115108]!). — Mont-Dore, Haute Boulari camp no. 3, 500 m, V.1938, R. Virot s.n. (P [P00115099]!).
DESCRIPTION
Epiphytic plant. Pseudobulbs bifoliate, ovate to turbinate, 8-(20-28)-44 × 4-(6-8)- 25 mm, with 4-5 internodes, bright orange on dry material, covered with 3 deciduous, broad, papyraceous and translucent cataphylls applied to the pseudobulb. Leaf: gutter-shaped pseudopetiole canaliculate, 2-4 mm, blade coriaceous ovate to elliptic 16-(27-39)- 72 × 7-(10-13)- 27 mm, apex obtuse. Inflorescence, 80- (140-240)- 420 mm, with 2-(4-7)-18 flowers, sometimes once branched, flower non resupinate, borne in a subterminal position of the pseudobulb, more or less hanging. Flower: Peduncle, 10 × 0.9 mm. Tepals yellow to brownish green. Median sepal, linear lanceolate, 18.7 × 4 mm, 5 visible veins. Lateral sepals lanceolate, curved proximally, 16.5 × 4.6 mm. Petals spatulate, curved proximally, 17 × 4.3 mm. Lip, 3-lobed, 10 × 5 mm. Hypochile thick, warty, greenish-white, thickened in the centre, extended by 3 very divergent flattened extensions, white with dark pink stains, 2.2-2.3 mm long and 0.6 mm wide. Lateral lobes erect, 3.3 × 1.9 mm, longitudinally striated dark pink, white proximally and bright orange distally, ovate, with a very attenuated tooth on the side showing the proximal lobule of D. petrophilum. Median lobe 3-lobulate, curved, 6 × 5 mm, greenish-white in the centre with a triangular central verrucous crest. Lateral lobules, triangular, slightly deflected, 1 × 1.2 mm, dark pink with greenish-white tip, panduriform median lobule with rounded apex, curved at the tip making it appear emarginate, 5.8 × 6 mm, dark pink. Column white, except the edge of the stigma which is dark pink (protruding 1 mm down), 6 × 2.5 mm with a 4 mm long mentum, and 1.9 mm deep at the point of attachment to the ovary. Stamen: anther cap (connective appendage) white, 1.1 mm wide and 1.4 mm high. Pollinia, 2, yellow, obovoid, 0.9 mm long. Stigma rectangular 1.3 mm wide and 1.6 mm high. Ovary, 4.5 × 1.4 mm. Fruit obovoid, (16-)19-23(-26) × (5-)6-8(-10) mm.
The vegetative system of the two species is very similar. However, the flowers as well as fruits have notable differences in size, shape and colour as summarised in Tables 1 and 2.
description: Published as part of Pignal, Marc, Laudereau, Christian, Gâteblé, Gildas & Laudereau, Pierre-Louis, 2022, Dendrobium petrophilum (Kraenzl.) Garay ex N. Hallé, a well-named species describing its unusual chasmophytic ecology, pp. 1-9 in Adansonia (3) (3) 44 (1) on pages 6-9, DOI: 10.5252/adansonia2022v44a1, http://zenodo.org/record/5864969