Aspidostemon humbertianum (Kosterm.) Rohwer

Werff, Henk Van Der, 2006, A revision of the Malagasy endemic genus Aspidostemon Rohwer & Richter (Lauraceae), Adansonia (3) 28 (1), pp. 7-44 : 24-26

11. Aspidostemon humbertianum (Kosterm.) Rohwer ( Figs 6C ; 7B )

Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 109: 78 (1987) . — Cryptocarya humbertiana Kostermans , Bulletin du Jardin botanique de l’État 27: 179 (1957). — Type: Madagascar, Andrambovato , Folongoina, Fort Carnot, [21°51’30”S, 47°26’30”E], 15.X.1952, fl., Service Forestier 6507 (holo-, P; iso-, P, TEF).

MATERIAL EXAMINED. — Madagascar. Andrambovato, Tolongoina, fl., Service Forestier 6507 ( P, TEF). — Andrambovato, Tolongoina, ster., Service Forestier 10987 ( P, TEF). — Andrambovato, Fort Carnot, ster., Service Forestier 11111 ( MO, P, TEF). — Parcelle B 11, Andrambovato, fl., Service Forestier 16248 ( P, TEF). — Ranomafana National Park, fr., Turk et al. 161 ( MO, P, TAN). — Ranomafana National Park, fr., Turk & Bernardin 207 ( MO, TAN). — Ranomafana National Park, fl., Turk & Randrianasolo 583 ( MO, P, TAN).

DESCRIPTION

Trees, to 25 m. Twigs terete, lenticellate, glabrous; terminal buds glabrous or with a fringe of hairs. Leaves opposite, 12-18 × 4-6 cm, elliptic, glabrous, base and apex acute, the margin flat, upper surface somewhat shiny, lower surface mat, reticulation weakly raised on the upper surface, more so on the lower surface, lateral veins not clearly recognizable, c. 10; petioles 7-9 mm long, canaliculate. Inflorescences in the axils of leaves, 1.5-2 cm long, moderately pubescent, the indument becoming denser towards the flowers; pedicels densely pubescent, 2 mm long. Flowers 3-3.5 mm in diam., with pale yellow tepals and maroon stamens, flat, wider than long; tepals 1.5 mm wide, 1 mm long, appressed, with a few hairs near the base, distally glabrous except for a fringe of hairs at the margin; stamens 3, petaloid, the locelli introrse, opening towards the tip of the stamens with only the flaps visible; staminodia of whorl II covered by the tepals, not visible, staminodia of whorl III with greatly expanded apices, fused, covering the center of the flowers, with a central pore for the style. Pistil and inside of the receptacle glabrous. Fruits ellipsoid, 3.5 × 2.5 cm, scurfy, the floral parts persisting on the top.

REMARKS

Aspidostemon humbertianum can be recognized by its rather large leaves with weakly raised reticulation on both surfaces, the pubescent inflorescences, the densely pubescent pedicels and the flat flowers with 3 fertile stamens. It is one of three species with pubescent inflorescences and flowers with 3 stamens and is the only one with flowers wider than long. Its distribution ranges from Andrambovato (Tolongoina) to Ranomafana ( Fig. 8 ). Only the collections from Ranomafana have an indication of altitude, from 950 to 1250 m, which is rather high for the genus.

Kostermans (1957) also cited Service Forestier 10967, a sterile collection, under A. humbertianum . This specimen has acuminate leaves, was collected near Lorihandava, Brickaville and represents a different species.

ALTITUDINAL DISTRIBUTION

950-1250 m.

PHENOLOGY

Flowers: October-November; fruits: November- December (probably from previous year).

VERNACULAR NAME

Longodranomena.

Figures

FIG. 6. — Species of Aspidostemon Rohwer & Richter: A, A. glandulosum Rohwer; B, A. grayi Van der Werff; C, A. humbertianum (Kosterm.) Rohwer; D, A. inconspicuum Rohwer. A, Service Forestier 16534, MO; B, Van der Werff et al. 12747, MO; C, Turk & Randrianasolo 583, MO; D, Service Forestier 12355, P.

FIG. 7. — Scanning electron microscope images of Aspidostemon Rohwer & Richter: A, A. grayi Van der Werff; B, A. humbertianum (Kosterm.) Rohwer; C, A. longipedicellatum Van der Werff; D, A. masoalense Van der Werff.A, Van der Werff et al. 12747, MO; B, Turk & Randrianasolo 583, MO; C, Van der Werff 12838, MO; D, Schatz & Modeste 3057, MO. Scale bars: 0.5 mm.

FIG. 8. — Distribution of Aspidostemon Rohwer & Richter in Madagascar:■, A.glandulosum Rohwer;▲, A. grayi Van der Werff;Ϙ, A. humbertianum (Kosterm.) Rohwer; Ϙ, A. inconspicuum Rohwer.