Borassus aethiopum Mart.

국표에 없다.

Morphology>General>Habit

Trunk ultimately reaching 20–30 m. tall, swollen at very base (85 cm. diameter), ± 40–50 cm. diameter at breast height, often with pronounced swelling to 80 cm. diameter about 10 m. above the base, at first covered with persistent leaf-bases, these eventually falling to leave a grey surface, marked with annular leaf scars.

Morphology>Leaves

Leaves ± 40 in the crown at maturity; leaf base ± 90 cm. long, split longitudinally down the mid-line, eventually also splitting opposite the petiole; petiole to 3.25 m. long by 15 cm. wide above the base, and 3 cm. thick, tapering to 7.5 cm. wide and 3 cm. thick near the lamina insertion, rounded abaxially, flattened or concave adaxially, edged with shiny, black, irregularly erose, sharp protuberances to 1–2 cm. high; adaxial hastula only slightly asymmetrical, ± 1 cm. high; abaxial hastula inconspicuous, ± 3 mm. high; costa short, ± 10 cm. long, the blade hence slightly costapalmate; blade radius ± 180 cm. from hastula to apex, shorter in outer regions; segments 60–80 or more, not all held in the same plane, stiff and only drooping at the tips in age, in length equalling ± half the radius, 5 cm. or more wide, bifid apically for up to 15 cm., with numerous very fine longitudinal veins, distinct lateral veins, and minute distant pale brown scales.

Morphology>Reproductive morphology>Inflorescences

Male inflorescence to ± 1.5 m. long with 3–6 partial inflorescences; peduncle ± 50 cm. long, ± 3 cm. in diameter at base; bracts tubular, to 45 cm. long by 7 cm. wide, coriaceous, finely striate, split to ± 17 cm., distally the first few bracts empty, the upper subtending branches terminating in (1–)3 rachillae; rachillae up to 35 cm. long by 3 cm. in diameter, brownish green, densely covered in ± 8 spirals of imbricate bracts, free portion of bracts about 10 mm. wide by 5 mm. high; cincinni bearing ± 9 flowers, emerging from the pit one at a time.

Female inflorescence ± 1–1.5 m. long, bearing 2–3 empty bracts to 50 cm. long by 7 cm. wide, occasionally branched once or twice; flower bearing portion of axis ± 50–75 cm. long, ± 4–5 cm. in diameter; bracts densely crowded, 3 cm. high by 12 cm. wide, connate laterally and forming pits.

Morphology>Reproductive morphology>Flowers

Male flowers subtended by 2 small bracteoles ± 3 mm. × 1 mm.; calyx to 7mm. long, tubular, with 3 very shallow to deep lobes; receptacle to 7.5 × 1 mm., bearing 3 small rounded somewhat cucullate corolla-lobes ± 2 mm. long; stamens 6; filaments very short bearing anthers ± 2 mm. × 0.5 mm.; pollen yellow. Female flowers solitary, borne with 2 bracteoles, each 2 cm. high by 3 cm. wide; sepals 3, imbricate, ± 1.5 × 2 cm.; petals 3, imbricate, ± 1 × 1.5 cm.; staminodal ring with 6 teeth to 4 mm. high; ovary ± 1 cm. in diameter, tipped with 3 stigmatic areas.

sex>Male

Male flowers subtended by 2 small bracteoles ± 3 mm. × 1 mm.; calyx to 7mm. long, tubular, with 3 very shallow to deep lobes; receptacle to 7.5 × 1 mm., bearing 3 small rounded somewhat cucullate corolla-lobes ± 2 mm. long; stamens 6; filaments very short bearing anthers ± 2 mm. × 0.5 mm.; pollen yellow. Male inflorescence to ± 1.5 m. long with 3–6 partial inflorescences; peduncle ± 50 cm. long, ± 3 cm. in diameter at base; bracts tubular, to 45 cm. long by 7 cm. wide, coriaceous, finely striate, split to ± 17 cm., distally the first few bracts empty, the upper subtending branches terminating in (1–)3 rachillae; rachillae up to 35 cm. long by 3 cm. in diameter, brownish green, densely covered in ± 8 spirals of imbricate bracts, free portion of bracts about 10 mm. wide by 5 mm. high; cincinni bearing ± 9 flowers, emerging from the pit one at a time.

sex>Female

Female flowers solitary, borne with 2 bracteoles, each 2 cm. high by 3 cm. wide; sepals 3, imbricate, ± 1.5 × 2 cm.; petals 3, imbricate, ± 1 × 1.5 cm.; staminodal ring with 6 teeth to 4 mm. high; ovary ± 1 cm. in diameter, tipped with 3 stigmatic areas. Female inflorescence ± 1–1.5 m. long, bearing 2–3 empty bracts to 50 cm. long by 7 cm. wide, occasionally branched once or twice; flower bearing portion of axis ± 50–75 cm. long, ± 4–5 cm. in diameter; bracts densely crowded, 3 cm. high by 12 cm. wide, connate laterally and forming pits.

Morphology>Reproductive morphology>Fruits

Ripe fruit usually dull orangey brown, somewhat shiny, borne with the much enlarged calyx and corolla; sepals in fruit 6 cm. high by 10 cm. wide; petals in fruit 7–8 cm. high by 12 cm. wide, erose-margined; fruit broadly ovoid, usually flat-topped, shape depending on number of seeds developing and on close-packing in the infructescence, up to 12 cm. high by 14 cm. in diameter or more, obscurely 3-angled; mesocarp up to 1 cm. thick, yellow and fragrant when ripe, with numerous longitudinal fibres embedded in soft pulp; pyrenes up to 3, 10 × 10 × 5 cm., with endocarp ± 7 mm. thick with 2 radially aligned internal longitudinal flanges, the outer to 1 cm. high the inner to 5 mm., penetrating the seed.

Morphology>Reproductive morphology>Seeds

Seeds 1 in each pyrene, with hard bony white homogeneous endosperm, almost completely filling the pyrene-cavity except for a small central space; embryo apical, top-shaped, ± 5 mm. long by 4 mm. wide.

Figures

Fig.2.

Habitat

Distribution locally very patchy, perhaps much influenced by man and elephants (J. Paiva (pers. comm.) records that not only elephant and man, but also lions are fond of the intensely fragrant fruit), occurring along water courses and, in drier areas, where a high water-table exists locally; often occurring in magnificent dense stands; sea-level to 1200 m.

Distribution

K7 P T1 T3 T4 T5 T6 T7 T8 U1 U2 U3 U4 Z widespread throughout the less dry areas of tropical Africa but apparently avoiding the perhumid areas of W. Africa     Africa   coastal towns

 

Borassus aethiopum Mart. | Plants of the World Online | Kew Science