Eremospatha macrocarpa

Eremospatha (eh-reh-moh-SPAH-thah) macrocarpa (mak-roh-KAR-pah)
Near Limbe, Cameroon. Leaf sheaths and basal leaflets. Photo by Dr. John Dransfield, Royal Botanic Gardens, Kew/Palmweb.
Scientific Classification
Genus: Eremospatha (eh-reh-moh-SPAH-thah) Species: macrocarpa (mak-roh-KAR-pah)
Synonyms
None set.
Native Continent
Africa
Morphology
Habit: Clustering Leaf type: Pinnate
Culture
Survivability index
Common names
large-fruit rattan palm

Habitat and Distribution

Benin, Central African Republic, Equatorial Guinea, Ghana, Guinea, Ivory Coast, Ivory Coast, Liberia, Nigeria, Sierra Leone, Zaire.

Near Limbe, Cameroon. Leaf sheaths and basal leaflets. Photo by Dr. John Dransfield, Royal Botanic Gardens, Kew/Palmweb.

Eremospatha macrocarpa is a very widespread and common species and is distributed from Senegal in West Africa through to the lowland forests of the Congo Basin. This species is extremely light demanding, occurring naturally in gap vegetation and forest margins. As a result of this, in common with other members of the genus, E. macrocarpa responds extremely well to selective logging activities and is a common component of regrowth vegetation. (T.C.H Sunderland, A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) in Phytotaxa 51. 2012)/Palmweb.

Description

Clustered slender to moderate palm climbing to 50-75 m, rarely to 150 m. Stems circular in cross-section, without sheaths, 10-18 mm in diameter, with 22-30 mm; internodes 13-16 cm long. Leaf sheath longitudinally striate, sparsely to moderately covered with light brown scale-like indumentum; ocrea entire, ± truncate saddle-shaped with a 2.5-4.0 cm rounded lobe adaxial to the leaf; knee absent. Juvenile stems up to 20 m long; stem with sheath, <1.5 cm in diameter; ocrea with distinct linear wrinkle on adaxial side; petiole <1 cm long; leaves bifid, up to 40 cm × 50 cm, deeply notched, lobes sharply triangular; cirrus up to 80 cm long, emerging from the centre; elaminate rachis often present on juvenile stems, 50-75 cm long. Leaves on mature stems sessile, up to 3.5 m long; rachis 1-1.5 m long, abaxially rounded, adaxially flattened, becoming trapezoid then rounded in cross-section distally, armed along the margins with inequidistant, reflexed thorns, becoming sparsely armed distally, underside of rachis with sparse light brown indumentum; cirrus 1.2-2 m long, unarmed; leaflets, up to 25 pairs on each side of the rachis, linear-lanceolate, abruptly contracted at the base, irregularly and narrowly praemorse at apex, 22-35 cm long × 2-2.5 cm broad at the widest point, concolorous, with 5-7 inconspicuous transverse veinlets 1-2 mm apart, armed along the margins with inequidistant, curved, forward-facing brown-tan spines; lowermost leaflets, smaller than the rest, linear-ovate, reflexed and laxly clasping the stem; acanthophylls ca.3 cm long, parallel to cirrus. Inflorescence glabrous, up to 55 cm long; peduncle 10-15 cm long; rachis 25-40 cm long, arching outwards, rarely straight; rachis bracts, acuminate, opposite proximally, alternate distally, 1-3 mm long, decreasing distally; rachillae distichous, arching vertically, sometimes horizontal, straight, 10-14 on each side, 12-18 cm long, decreasing distally, adnate to the inflorescence axis for 0.5-1.5 mm, with <1 mm-long triangular incomplete bracts subtending each dyad. Flowers borne in close pairs; calyx 3 mm long × 6 mm wide at the mouth, with 3 distinct, rounded, lobes; corolla 10 mm long × 4 mm wide, divided to ¼ of its length; stamens united into 5 mm-long epipetalous ring; free filaments <0.5 mm; anthers <1 mm long; ovary 4 mm × 2.5 mm tipped with ca.2 mm-long style. Fruit at maturity 1-seeded, rarely 2-seeded, ± cylindrical, 2.2-2.6 cm long × 1-1.5 cm wide, with 17-24 rows of vertical scales. Seed compressed, 1.8-2 cm long × 1.4-1.8 cm wide × 1 cm thick, flattened on one side or with a shallow depression, embryo lateral, raised, opposite the flattened side. (T.C.H Sunderland, A taxonomic revision of the rattans of Africa (Arecaceae: Calamoideae) in Phytotaxa 51. 2012)/Palmweb. Editing by edric.

Culture

Eremospatha macrocarpa has a long germination period and high initial seed mortality. In Cameroon an annual extension growth of 3.2 m has proven possible, making Eremospatha macrocarpa very suitable for short rotation agroforestry. All Eremospatha species are pleonanthic, i.e. the stems do not die after flowering. The seeds of most African rattans are dispersed primarily by birds (especially hornbills). However, primates, predominantly drills and mandrills (two species of forest primate related to the baboon), chimpanzees and gorillas are also key dispersal agents, as are elephants. Predation by rodents accounts for some additional dispersal. (prota4u.org)

In Africa rattans are usually exploited from wild sources, and there is little cultivation despite favourable ecological factors and growth rates that suggest cultivation would be feasible. This contrasts with the situation in South-East Asia, where traditional rattan cultivation practices exist such as the cultivation in mixed gardens by sedentary cultivators or in recently burned forests by shifting cultivators. In Ghana, Nigeria and Cameroon community-based trials concentrating on the introduction of rattans into agro-forestry systems and enrichment planting of farm bush and secondary forest have been established but farmer adoption has remained low. (prota4u.org)

Propagation by seed is possible, but germination is slow and seed mortality high. Trials in Cameroon showed germination rates of 32.5%, with a time to first emergence of 96 days. In nursery trials with suckers in Côte d’Ivoire shoots emerged 43–93 days after planting. In on-farm trials in Ghana, Nigeria and Cameroon a high post-planting mortality was recorded, which is attributed to neglect and predation by rodents. (prota4u.org)

Comments and Curiosities

Etymology: The specific epithet from the Latin, literally; large-fruits.