Octoknema Pierre

This genus is accepted, and its native range is W. Tropical Africa to Tanzania.

[KBu]

Gosline, G. & Malécot, V. Kew Bull (2011) 66: 367. https://doi.org/10.1007/s12225-011-9293-9

Distribution
Octoknema is restricted to Africa where it is largely Guineo-Congolian with one outlier in the eastern arc mountains. It occurs in wet forests from Guinea-Conakry to Congo (Kinshasa), and in Tanzania, with a main centre of diversity in Cameroon and Gabon (Map 1). Its distribution pattern is similar to that of numerous forest genera of wet tropical Africa:
Morphology General Habit
Evergreen, dioecious shrubs (Octoknema genovefae, O. ogoouensis Malécot & Gosline, O. sp C), small trees, or trees to 30 m tall (O. orientalis, O. borealis); old branches glabrous, bark whitish to brown, commonly smooth; young twigs glabrous to densely pubescent and floccose, bark whitish to dark brown; indumentum of all parts of white to dark brown stellate hairs, 0.25 – 0.3 mm long, erect or scale-like (O. affinis), some species with semi-dendritic hairs to 1.5 mm long; terminal buds and very young leaves densely pubescent, often with dendritic hairs
Morphology Leaves
Leaves alternate, distichous, estipulate, petiole 0.8 – 4 cm long, sparsely to densely pubescent, terete or canaliculate, with or without an apical pulvinus; leaf blade simple, elliptic to obovate to narrowly elliptic, leaf apex acute, rounded or obtuse, acumen rounded to pointed or spathulate (rarely absent), leaf base rounded, cuneate, cordate, or slightly peltate, margin entire; primary vein prominent on lower surface, sparsely or densely pubescent below; secondary veins 4 – 11 pairs, forming an angle of 30 – 60° with the primary vein, ascendant, prominent below, glabrescent or glabrous below; tertiary veins commonly apparent, areolae in mature leaves glabrous or with uniformly spaced stellate hairs (O. klaineana, O. sp D)
Morphology Reproductive morphology Flowers
Flowers actinomorphic, pentamerous (except O. chailluensis Malécot & Gosline, which is trimerous), sepals (3) 5 reduced or absent, sometimes represented by denser concentrations of hairs below the petals, petals (3) 5, fused at the base, external surface pubescent or glabrous, internal surface glabrous sometimes with a central tuft of filiform hairs, or with a contorted ruminate glandular surface Female flowers at least 1.5 mm in diam., at least 2.5 mm long, epigynous with (3) 5 staminodes opposite petals, sometimes with glands alternating with staminodes; ovary densely or sparsely pubescent, 3-carpellate; style terminated by 3 radiate flattened forked or laciniate stigmatic lobes (often appearing more); gynoecium 1-celled, placentation free-central, ovules 3
Morphology Reproductive morphology Fruits
Fruit drupaceous, prolate, globose or ovoid, 1 – 4 × 0.8 – 2.5 cm, dark green, yellow, orange or bright red when mature, glabrescent, sparsely pubescent, or pubescent, apex with persistent remnants of corolla, staminodes, and styles forming a small “crown” 1 – 3 mm in diam.; epicarp smooth, verrucose or longitudinally grooved, mesocarp smooth and hard in immature fruit, 1 – 3 mm thick in mature fruit, soft (persistent wrinkled pulp in secco) not developing until fully mature, endocarp to 1.5 mm thick, woody and hard with 6 or 9 – 11 (one or more often reduced) internal longitudinal lamina partially penetrating the single ruminate seed.
Morphology Reproductive morphology Inflorescences
Inflorescences spicate or rarely slightly branched, solitary, axillary, sparsely to densely pubescent with small, more or less distinct, floral bracts, usually obscured by the hairs Male inflorescence racemose, 2 to more than 15 cm long; peduncle 3 – 25 mm long; flowers densely to sparsely arranged, solitary or in clusters of few to many Male flowers: buds 1 – 3.5 mm in diam.; pedicel 2 – 5 mm long, thin (0.5 – 1 mm in diam.), or very thin (<0.5 mm diam.), sparsely pubescent or pubescent; stamens (3) 5 opposite petals, apparently epipetalous or free, anther dorsibasifixed (sensu Stauffer 1957) and bilocular, filament below anther as long as or longer than the anther, flattened or round; glands present in some species forming a disk surrounding the pistillode; pistillode truncate, columnar or pyramidal-Female inflorescence solitary, axillary, spicate, 0.5 to more than 10 cm long; peduncle 2 to 50 mm long; 3 to 12 flowers per inflorescence

[FTEA]

Olacaceae, G. Ll. Lucas. Flora of Tropical East Africa. 1968

Morphology General Habit
Trees or shrubs
Morphology Leaves
Leaves alternate, entire, glabrous to densely stellate-hairy
Morphology Reproductive morphology Inflorescences
Inflorescence axillary, racemose
Morphology Reproductive morphology Flowers
Flowers unisexual by abortion Female flowers: sepals absent or minute; petals 5, borne on the outer edge of the receptacle; staminodes 5; filaments without anther-thecae, opposite petals, alternating with disk-lobes; ovary 1 or 3(–4)-locular, inferior; ovules 1 per locule; style short; stigma 3–5-lobed, irregularly divided Male flowers: sepals absent (? always); petals (4–)5; stamens 5, opposite the petals and alternating with the disk-lobes; anthers dithecous; ovary rudimentary
sex Male
Male flowers: sepals absent (? always); petals (4–)5; stamens 5, opposite the petals and alternating with the disk-lobes; anthers dithecous; ovary rudimentary
sex Female
Female flowers: sepals absent or minute; petals 5, borne on the outer edge of the receptacle; staminodes 5; filaments without anther-thecae, opposite petals, alternating with disk-lobes; ovary 1 or 3(–4)-locular, inferior; ovules 1 per locule; style short; stigma 3–5-lobed, irregularly divided
Morphology Reproductive morphology Fruits
Fruit a drupe, ellipsoid or spherical, surmounted by persistent petals, single-seeded
Morphology Reproductive morphology Seeds
Seed furrowed longitudinally by inner surface of the endocarp.

Doubtfully present in:

Equatorial Guinea

Native to:

Cameroon, Central African Repu, Congo, Gabon, Ghana, Guinea, Ivory Coast, Liberia, Nigeria, Sierra Leone, Tanzania, Zaïre

Octoknema Pierre appears in other Kew resources:

Date Reference Identified As Barcode Type Status Has image?
Troupin, G. [3437], Congo, DRC 21910.000 No

First published in Bull. Mens. Soc. Linn. Paris 2: 1290 (1897)

Accepted by

  • Gosline, G. & Malécot, V. (2011 publ. 2012). A monograph of Octoknema (Octoknemaceae - Olacaceae s.l.) Kew Bulletin 66: 367-404. Royal Botanic Gardens, Kew.

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Flora of West Tropical Africa

  • Mildbr. in E. & P. Pflanzenfam. 16B: 42 (1935).
  • in Bull. Soc. Linn. Paris 2: 1290 (1897)

Flora of Tropical East Africa

  • Mildbr. in E. & P. Pf., ed. 2, 16B: 45 (1935)
  • in Bull. Soc. Linn. Paris 2: 1290 (1897)

  • Flora of Tropical East Africa

    Flora of Tropical East Africa
    http://creativecommons.org/licenses/by-nc-sa/3.0

  • Herbarium Catalogue Specimens

  • Kew Backbone Distributions

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

  • Kew Bulletin

    Kew Bulletin
    http://creativecommons.org/licenses/by-nc-sa/3.0

  • Kew Names and Taxonomic Backbone

    The International Plant Names Index and World Checklist of Selected Plant Families 2022. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0