Amaranthus L.
Erect or prostrate herbs. Fruit dry, membranous Amaranthus
Bracts with short points or none, shorter or not much longer than the perianth. Perianth segments usually 3, if 5 then fruit with 3 swollen styles. Fruit indehiscent or bursting irregularly.
Flowers in axillary clusters.
Perianth segments 5, 2–3 mm long; spathulate, mucronate. Styles 3, swollen. Fruit wrinkled and swollen below, slightly longer than perianth. Uncommon. Introd. from NW NSW. Boggabri Weed Amaranthus mitchelli
Perianth segments 3, 5 mm long, spathulate, acuminate or emarginate. Bracts and bracteoles shorter than the perianth Fruit oblong, much longer than the perianth, wrinkled, indehiscent, with 2–3 prominent styles