Ocotea ambrensis van der Werff, 2013

Werff, Henk Van Der, 2013, A revision of the genus Ocotea Aubl. (Lauraceae) in Madagascar and the Comoro Islands, Adansonia (3) 35 (2), pp. 235-279 : 241

1. Ocotea ambrensis van der Werff , sp. nov.

( Figs 1 , 2 )

Ocoteae racemosae similis, sed tepalis persistentibus, bracteis basi gemmarum terminalibus magnis recedit.

TYPUS. — Madagascar. Prov. Antsiranana, Parc National de Montagne d’Ambre , 12°32’S, 49°11’E, 900-1100 m, 16-20.XI.1992, fls, Malcomber, Leeuwenberg, van Bergen, Andriatiana & Randriamampionona 1817, (holo-, P! ; iso-, MO! [ 6240678 ], TAN).

PARATYPES. — Madagascar. Antsiranana, Montagne d’Ambre PN, 12°32’S, 49°07’E, fr., Andrianantoanina & Solotiana 60 ( MO, P [ P01977609 ], TAN) ; s. loc., Andrianantoanina & Solotiana 69 ( MO, TAN) ; Parc National de la Montagne d’Ambre, 12°27’S, 49°13’E, fr., Andrianantoanina & Rocsce 270 ( MO, P [ P01977608 ], TAN) ; Roussettes, Montagne d’Ambre, fls, Service Forestier 5467 ( P [ P01977610 ], TEF) ; Montagne d’Ambre, Service Forestier ( Capuron ) 11290 ( P [ P01977611 ], TEF) ; Montagne d’Ambre, Trigui et al. 518 ( G, MO, P [ P01976697 ]).

ALTITUDINAL DISTRIBUTION. — None of the collections of O. ambrensis sp. nov. gives a specific altitude; instead ranges of altitude are given. The lowest is from 250- 500 m, the highest from 990-1100 m.

PHENOLOGY. — Flowering: November-December; fruiting: April (young fruits), August (older fruits).

DESCRIPTION

Trees, to 30 m. Twigs slightly angular, moderately appressed pubescent, becoming glabrous with age; terminal buds densely white pubescent, often with pubescent bracts, 4-6 mm long, at their base. Leaves 5-9 × 1.5-3.5 cm, elliptic, alternate, chartaceous, base and apex acute, margin flat, glabrous or nearly so, the lower surface minutely gland-dotted, this less visible on older leaves, venation immersed on upper surface, slightly raised on lower surface, lateral veins poorly visible, 5-7 on each side, domatia absent. Inflorescences crowded along leafless short shoots, 2-4 cm long, racemose or paniculatecymose, moderately to sparsely pubescent, some bracts persisting on the inflorescences, but these less conspicuous than the bracts near the terminal buds. Flowers cream white, 5-6 mm in diameter, the tepals spreading at anthesis; tepals 2-2.5 mm long, sparsely pubescent outside, densely pubescent inside, stamens 9, all 4-celled, 1 mm long, the filaments short, pubescent; glands present at the base of the inner stamens; staminodia clavate, 0.7 mm long, the thickened head glabrous, the filament pubescent; pistil glabrous, 1.5 mm long, the style as long as the ovary, stigma peltate, receptacle glabrous inside. Young fruits (1 cm in diameter) enclosed in the cupule, this crowned by the persisting tepals, resembling small rose hips, older fruits (approaching 2 cm in diameter) ⁴⁄5 enclosed in the cupule, this splitting and with teeth-like remnants of the tepals; mature fruits 2.5 × 1.5 cm, cupule deeply cup-shaped, 1.8 cm in diameter, with teeth-like remnants of the tepals.

REMARKS

Ocotea ambrensis sp. nov. resembles the widespread and variable O. racemosa (Danguy) Kosterm. Kostermans (1957) annotated the sole specimen he saw of O. ambrensis sp. nov. as O. laevis Kosterm. , which I treat as a synonym of O. racemosa . However, the four collections of O. ambrensis sp. nov. made in the last 15 years show consistent differences from O. racemosa , viz. the large, persistent bracts at the base of the terminal buds (lacking in O. racemosa ), the persistent tepals on the cupule (tepals deciduous in fruit in O. racemosa ), the very deep cupule (vs shallow cupules), the thinner leaves and the minute, dense gland dots at the lower surface of the leaves, at least of the flowering specimens (gland dots lacking in O. racemosa ). The new species, known only from the Montagne d’Ambre in the far North, is also geographically separated from O. racemosa .

Figures

FIG. 1. — Isotype of Ocotea ambrensis van der Werff, sp. nov.

FIG. 2. — Distribution of Ocotea ambrensis van der Werff,sp. nov. (N), O. auriculiformis Kosterm. (p), O. caudatifolia Kosterm. (l) and O. rigidifolia Kosterm. (Ì).