Euphorbiaceae

Codiaeum Rumph. ex A.Juss.

First published in Euphorb. Gen.: 33 (1824), nom. cons.
This genus is accepted
The native range of this genus is Malesia to SW. Pacific.

Descriptions

Timothy M. A. Utteridge and Laura V. S. Jennings (2022). Trees of New Guinea. Kew Publishing. Royal Botanic Gardens, Kew

Distribution
A small genus of c. 15 species, with five species in New Guinea; Codiaeum variegatum (L.) Blume is widely cultivated throughout the tropics (and in temperate regions as a house plant and in glasshouses – often called, erroneously, a ‘Croton’).
Morphology General Habit
Shrubs or small trees to 15 m Plants monoecious
Morphology General
Sap sometimes present, clear
Morphology General Indumentum
Indumentum of simple hairs
Morphology Leaves Stipules
Stipules minute
Morphology Leaves
Leaves extremely variable in size and shape (sometimes up to 60 cm long), alternate, simple, margins entire (but often irregularly lobed), penninerved
Morphology Reproductive morphology Inflorescences
Inflorescences axillary in the axil of a modified, reduced leaf, racemose, often elongate (up to 50 cm long)
Morphology Reproductive morphology Flowers
Staminate flowers: sepals 3–6, imbricate; petals usually present but small and minute, sometimes absent; stamens 15–100, free, anthers basifixed, erect; disk glands small, alternating with the petals; pistillode absent
Morphology Reproductive morphology Flowers Gynoecium Pistil
Pistillate flowers: sepals as staminate flowers; disk entire, cupular; ovary 3-locular; styles spreading or recurved, elongate, simple
Morphology Reproductive morphology Fruits
Fruit 3-locular capsule, subglobose, somewhat lobed, smooth. Seeds smooth with a marbled or spotted testa, caruncle present.
Ecology
Members of the genus can be found in the coastal habitats, swamp forest, the understorey of primary rain forest and montane forests from sea level up to c. 1600 m; note the commonly cultivated species Codiaeum variegatum, can be found planted in gardens and villages throughout the region.
Recognition
The leaves are extremely variable depending on the habitat and within the same taxon can be, for example, narrowly lanceolate (rheophytic forms) to cuneate-obovate up to 20 cm long (in forest) and have been recorded up to 50 cm long or more in swamp forest. The plants are monoecious with racemose inflorescences usually subtended by a small orbicular reduced leaf, and the staminate flowers have petals (though often very small), and the pistillate flowers have elongated styles that are not bifid or lobed; the seeds are spotted.
[TONG]

Euphorbiaceae, A. R.-Smith. Flora of Tropical East Africa. 1987

Morphology General Habit
Monoecious or occasionally dioecious shrubs or small trees with or without a simple indumentum
Morphology Leaves
Leaves alternate, petiolate, minutely stipulate or not, simple and entire or occasionally trilobate, sometimes with the lamina recurved, twisted or interrupted, penninerved, eglandular or subeglandular at the base
Morphology Reproductive morphology Inflorescences
Inflorescences axillary or subterminal, often subtended by a small orbicular leaf, laxly racemose, solitary or sometimes binate, usually unisexual, pedunculate; ♂ bracts 1–6-flowered; ♀ bracts 1-flowered
Morphology Reproductive morphology Flowers
Male flowers: pedicels slender, articulate; sepals (3–)5(–6), free, imbricate; petals (3–)5(–6), small, minute or 0; disc-glands 5–15, small, free, alternating with the petals; stamens 15–100, filaments free, anthers erect, extrorse, dorsifixed, connective broad, thecae apically confluent, longitudinally dehiscent; pistillode 0 Female flowers: pedicels short and stouter than in ♂, not articulate; sepals smaller than in ♂, otherwise ± similar; petals 0; disc shallowly cupular, entire or ± so; ovary 3-locular, with 1 ovule per locule; styles 3, shortly connate at the base, spreading or recurved, simple, rarely bipartite
sex Male
Male flowers: pedicels slender, articulate; sepals (3–)5(–6), free, imbricate; petals (3–)5(–6), small, minute or 0; disc-glands 5–15, small, free, alternating with the petals; stamens 15–100, filaments free, anthers erect, extrorse, dorsifixed, connective broad, thecae apically confluent, longitudinally dehiscent; pistillode 0
sex Female
Female flowers: pedicels short and stouter than in ♂, not articulate; sepals smaller than in ♂, otherwise ± similar; petals 0; disc shallowly cupular, entire or ± so; ovary 3-locular, with 1 ovule per locule; styles 3, shortly connate at the base, spreading or recurved, simple, rarely bipartite
Morphology Reproductive morphology Fruits
Fruit globose or tridymous, dehiscing into 3 bivalved cocci
Morphology Reproductive morphology Seeds
Seeds smooth, shiny, marbled, carunculate; testa crustaceous; albumen fleshy; cotyledons broad, flat.
[FTEA]

Euphorbiaceae, A. Radcliffe-Smith. Flora Zambesiaca 9:4. 1996

Morphology General Habit
Monoecious or occasionally dioecious shrubs or small trees with a simple indumentum, or glabrous.
Morphology Leaves
Leaves alternate, petiolate, minutely stipulate or stipules absent, simple, entire or 3-lobed, occasionally the lamina contorted or interrupted along the midrib, penninerved, eglandular or ± so.
Morphology Reproductive morphology Inflorescences
Inflorescences axillary or subterminal, racemose, solitary or paired, usually unisexual, pedunculate; male bracts 1–6-flowered; female bracts l-flowered.
Morphology Reproductive morphology Flowers
Male flowers: pedicels slender, jointed; sepals (3)5(6), closely imbricate; petals (3)5(6), small, minute or absent; disk glands 5–15, free, alternipetalous; stamens 15–100, filaments free, anthers erect, extrorse, dorsifixed, connective broad, thecae apically confluent, longitudinally dehiscent; pistillode absent. Female flowers: pedicels shorter and stouter than in the male, not jointed; sepals smaller than in the male, otherwise ± similar; petals absent; disk shallowly cupular, subentire or shallowly 5-lobed; ovary 3-locular, 1 ovule per locule; styles 3, shortly connate at the base, spreading or recurved, usually simple.
Morphology Reproductive morphology Fruits
Fruit globose or 3-lobed, dehiscing septicidally into 3 bivalved cocci; pericarp thin; endocarp thinly woody; columella persistent.
Morphology Reproductive morphology Seeds
Seeds ovoid to subglobose, carunculate; testa smooth, shiny, marmorate, crustaceous; albumen fleshy; cotyledons broad, flat.
[FZ]

Sources

  • Flora Zambesiaca

    • Flora Zambesiaca
    • http://creativecommons.org/licenses/by-nc-sa/3.0

  • Flora of Tropical East Africa

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

  • Herbarium Catalogue Specimens

    • 'The Herbarium Catalogue, Royal Botanic Gardens, Kew. Published on the Internet http://www.kew.org/herbcat [accessed on Day Month Year]'. Please enter the date on which you consulted the system.

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2025. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2025. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0

  • Trees of New Guinea

    • Trees of New Guinea
    • http://creativecommons.org/licenses/by-nc-sa/3.0