Amaranthus L.

First published in Sp. Pl.: 989 (1753)
This genus is accepted
The native range of this genus is Cosmopolitan.

Descriptions

Amaranthaceae, C. C. Townsend. Flora Zambesiaca 9:1. 1988

Morphology General Habit
Annual or more rarely perennial herbs, glabrous or furnished with short and gland-like or multicellular hairs.
Morphology Leaves
Leaves alternate, long-petiolate, simple and entire or sinuate.
Morphology Reproductive morphology Inflorescences
Inflorescence basically cymose, bracteate, consisting entirely of dense to lax axillary clusters or the upper clusters leafless and more or less approximate to form a lax or dense “spike” or panicle.
Morphology Reproductive morphology Flowers
Flowers monoecious or (not in Africa) dioecious, bibracteolate.
Morphology Reproductive morphology Flowers Perianth
Perianth segments (2) 3–5, free or connate at the base, membranous, those of the female flowers sometimes slightly accrescent in fruit.
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens free, usually similar in number to the perianth segments; anthers bilocular.
Morphology Reproductive morphology Flowers Gynoecium Stigma
Stigmas 2–3.
Morphology Reproductive morphology Flowers Gynoecium Ovary Ovules
Ovule solitary, erect.
Morphology Reproductive morphology Fruits
Fruit a dry capsule, indehiscent, irregularly rupturing or commonly dehiscing by a circumcissile lid.
Morphology Reproductive morphology Seeds
Seeds usually black and shining, testa thin; embryo annular, endosperm present.
[FZ]

George R. Proctor (2012). Flora of the Cayman Isands (Second Edition). Royal Botanic Gardens, Kew

Morphology General Habit
Annual erect or prostrate herbs, glabrous or pubescent; leaves entire, long-petiolate
Morphology Reproductive morphology Flowers
Flowers unisexual, monoecious, in axillary clusters or terminal panicles; perianths of 3–5 equal segments. Stamens 2–5; filaments free; staminodes none; anthers 2-celled
Morphology Reproductive morphology Flowers Gynoecium Ovary
Ovary with 2–3 stigmas
Morphology Reproductive morphology Fruits
Fruit compressed, indehiscent or circumscissile, often with 2 or 3 beaks
Morphology Reproductive morphology Seeds
Seed compressed, with annular embryo.
Distribution
A world-wide genus of about 60 tropical and temperate species.
[Cayman]

M. Thulin et al. Flora of Somalia Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Morphology General Habit
Annual or more rarely perennial herbs, glabrous or furnished with short and gland-like or multicellular hairs
Morphology Leaves
Leaves alternate, long-petiolate, entire or sinuate
Morphology Reproductive morphology Inflorescences
Inflorescence basically cymose, bracteate, formed of dense to lax axillary clusters or the upper clusters leafless and ± approximate to form a dense or lax “spike” or panicle
Morphology Reproductive morphology Flowers
Flowers dioecious (not in Somalia) or monoecious
Morphology Reproductive morphology Flowers Tepal
Tepals (2–)3–5, free or almost so, those of the female flowers somewhat accrescent in fruit
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens usually isomerous with the tepals, free
Morphology Reproductive morphology Flowers Gynoecium Ovary
Ovary 1-ovulate
Morphology Reproductive morphology Flowers Gynoecium Stigma
Stigmas 2–3
Morphology Reproductive morphology Fruits
Fruit a dry, indehiscent, irregularly rupturing or circumscissile capsule
Morphology Reproductive morphology Seeds
Seed usually compressed, black and shining.
Distribution
About 100 species, chiefly in the tropical to warm temperate regions of the world, occurring as casual weeds in cooler temperate regions.
[FSOM]

Amaranthaceae, C.C. Townsend. Flora of Tropical East Africa. 1985

Morphology General Habit
Annual or more rarely perennial herbs, glabrous or furnished with short and gland-like or multicellular hairs, dioecious (not in E. Africa) or monoecious
Morphology Leaves
Leaves alternate, long-petiolate, simple and entire or sinuate
Morphology Reproductive morphology Inflorescences
Inflorescence basically cymose, bracteate, consisting entirely of dense to lax axillary clusters or the upper clusters leafless and ± approximate to form a lax or dense “spike” or panicle
Morphology Reproductive morphology Flowers
Flowers bibracteolate; perianth-segments (2–)3–5, free or connate at the base, membranous, those of ♀ slightly accrescent in fruit
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens free, usually similar in number to the perianth-segments; anthers bilocular
Morphology Reproductive morphology Flowers Gynoecium Stigma
Stigmas 2–3; ovule solitary, erect
Morphology Reproductive morphology Fruits
Fruit a dry capsule, indehiscent, irregularly rupturing or commonly dehiscing by a circumscissile lid
Morphology Reproductive morphology Seeds
Seeds usually black and shining; testa thin; embryo annular, endosperm present.
[FTEA]

Sources

  • Flora Zambesiaca

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

    • Flora of Somalia
    • 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
  • Flora of the Cayman Islands

    • Flora of the Cayman Islands
    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • Herbarium Catalogue Specimens

  • 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