Sapotaceae

Amorphospermum F.Muell.

First published in Fragm. 7: 112 (1870)
This genus is accepted
The native range of this genus is New Guinea to E. Australia.

Descriptions

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

Distribution
A monotypic genus, represented by Amorphospermum antilogum F.Muell., restricted to New Guinea and north-east Australia.
Morphology General Habit
Hermaphroditic shrub or tree to c. 30 m, sometimes buttressed
Morphology Leaves
Leaves spirally arranged and alternate; secondary venation weak, often branching well inside the margin, joining in diffuse loops, becoming brochidodromous; tertiary venation admedial, ± parallel to the secondaries, somewhat reticulate, faint
Morphology Reproductive morphology Inflorescences
Inflorescences in ramiflorous or axillary fascicles
Morphology Reproductive morphology Flowers
Flowers bisexual, cup-shaped with revolute corolla lobes; calyx a single whorl of 5(–6) free, quincuncial sepals; corolla lobes 5 (–8), entire; stamens 5(–8), one opposite each corolla lobe, well exposed in open flowers, inserted in corolla tube orifice; staminodes absent; ovary usually 5-locular; style simple
Morphology Reproductive morphology Fruits
Fruit purple to purple black, globose, 1-seeded; cotyledons plano-convex with included radicle and no endosperm.
Ecology
Amorphospermum antilogum occurs in lowland rain forests, but is poorly known in New Guinea.
Recognition
The genus is recognisable by a combination of poorly visible venation, obscured by the indument below, usually 5-merous flowers with sepals in 1 whorl, absence of staminodes and a 1-seeded globose fruit. In the field, the greyish to brownish indument on the lower leaf surface is in sharp contrast to the darker green upper surfaces.
[TONG]

Sources

  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. 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 2024. 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