Jumellea arborescens H. Perrier

Rakotoarivelo, Fanny, Pailler, Thierry & Faliniaina, Lucien, 2013, Revision of the genus Jumellea Schltr. (Orchidaceae) from the Comoros Archipelago, Adansonia (3) 35 (1), pp. 33-46 : 40-42

3. Jumellea arborescens H. Perrier

( Fig. 5 )

Notulae Systematicae (Paris), 7 (2): 58-59 (1938); Perrier de la Bâthie in Humbert H. (éd.), Flore de Madagascar, 49e fam., Orchidées 2: 188 (1941); Du Puy et al., hve Orchids of Madagascar, 1 st éd. (1999); Stewart et al., Angraecoid orchids: 186 (2006); Hermans et al., hve Orchids of Madagascar 2nd éd. (2007); Cribb & Hermans, Field Guide to the Orchids of Madagascar (2009).

— Type: Madagascar, Tsinjoarivo, 1400 m, II.1925, Perrier de la Bâthie 16968 (holo-, P! [ P00090529 ]).

SPECIMENS EXAMINED. — Comoros. Grande Comore, flanc Ouest du Karthala, 11°45’S, 43°19’E, 1630 m, 17.VIII. 2000, Brionnaud et al. 72 ( K!). — Grande Comore, La Grille Massif, 11˚28’09.2’’S, 46˚51’38.3’’E, 853 m, 27.II.2009, Rakotoarivelo et al. 058 ( REU!). — Mohéli, Oualah II, 12°21’06.4’’S, 43°45’43.6’’E, 401 m, 2.III.2009, Rakotoarivelo et al. 123 ( REU!).

Mayotte. Mont Choungui, 18.XI.2002, Barthelat et al. 1087 ( K!).

Madagascar. Fianarantsoa, Andringitra, circuit Asaramanitra , 22°08’37’’S, 046°53’17.6’’E, 1731 m, 13.I.2010, Rakotoarivelo et al. 218 ( TAN!) ; circuit Imarivolanitra, 22°11’36.9’’S, 46°54’00.6’’E, 2257 m, 13.I.2010, Rakotoarivelo et al. 223 ( TAN!). — Antananarivo, Ambatolampy, Manjakatompo , 19°21’17.8’’E, 47°18’32’’S, 1813 m, 19.I.2010, Rakotoarivelo et al. 235 ( TAN!).

DESCRIPTION

Epiphyte or lithophyte, up to 70 cm tall. Stems caespitose, erect or pendant, round in section (5-6 mm). Leaves distichous or spirodistichous, conduplicate at the base and flat in the upper part, elliptical (8-15 × 1.5-2.3 cm), slightly bilobed at the apex, dark green color. Leaf sheaths adnate to the stem. Inflorescence appearing mostly by pair, piercing the leaf sheath. Peduncle long (5-6 cm), covered up to third by 4-sterile bracts. Pedicellate ovary 9.1-10.1 cm long, with a fertile bract (1-1.5 cm) inserted at the base. Fertile and sterile bracts tubuliform. Flower white, the perianth parts crispate at the base. Median sepals upright or slightly curved, same size as the lateral sepals, oblong (21-25 × 2-4 mm), acute. Petals oblong, narrower than the sepals (23-26 × 3-4 mm), acute. Lip lanceolate (23-27 × 8-10 mm), contracted at the base, with a short keel (7-8 mm), widened in the half upper part, acute at the apex. Spur filiform (9-12.7 cm), angled at the base and then curved, attenuate at the apex. Column 3-4 mm high, lobes of the rostellum acute at the tips. Anther cap with a fine crest covering the lobes of the rostellum at its upper and joined tips. Capsule fusiform of 50-75 mm long.

DISTRIBUTION

Madagascar, Comoros, Mayotte. In the humid forest, from 800 to 1850 m elevation.

REMARKS

Jumellea confusa was recorded in Comoros archipelago ( Stewart 1968; Du Puy et al. 1999; Stewart et al. 2006; Pailler et al. 2009). But according to the collections type numbers P00090529 and P00090515, belonging respectively to J.arborescens and J. confusa , the specimens from the Comoros assigned to J. confusa were misidentified and belong to J. arborescens . Differences between these two species are mainly in the leaf shape which is elliptical for J. arborescens but oblong for J. confusa . Compared to J. arborescens from Madagascar inflorescences size and number are larger for individuals from the Comoros. ( Bosser & Lecoufle 2011).

Figures

FIG. 5. — Jumellea arborescens H. Perrier: A, habit; B, pieces of the perianth; C, peduncle, pedicellate ovary and spur; D, column, side view. Abbreviations: ms, median sepal; ls, lateral sepals; pt, petals; lp, lip. Scale bars: A, 3 cm; B, 1 cm; C, 2 cm; D, 2.5 mm.