Leaves opposite or whorled, rarely scattered, penniveined or with curved longitudinal venation.
Inflorescences usually axillary, sometimes arising between the nodes or from runners, primarily a pedunculate, many-rayed umbel of triads, often variously reduced, bract single beneath each flower. Corolla free; usually 4-, 5-, or 6-merous. Anthers basifixed, immobile. Styles usually articulate at the base.
| | Key to the species | |
| 1 | Leaves terete | 2 |
| Leaves flat | 4 |
| 2 | Corolla glabrous | Amyema preissii |
| Corolla tomentose
Back to 1 | 3 |
| 3 | Tomentum of the corolla short, grey; corolla slender | Amyema cambagei |
| Tomentum of the corolla long, white; corolla robust
Back to 2 | Amyema linophylla subsp. orientalis |
| 4 | Inflorescences capitate, consisting of 2 sessile triads | Amyema maidenii |
| Inflorescences umbellate
Back to 1 | 5 |
| 5 | Flowers in dyads or triads, all pedicellate | 6 |
| Flowers in triads or tetrads with at least the central flower sessile
Back to 4 | 7 |
| 6 | Rays 2; flowers in dyads | Amyema bifurcata |
| Rays 3–6; flowers in triads
Back to 5 | Amyema miquelii |
| 7 | Calyx woolly-white below, glabrous or nearly so above | 8 |
| Calyx not as above
Back to 5 | 9 |
| 8 | Rays 2; lateral flowers of the triads shortly pedicellate | Amyema conspicua |
| Rays usually 4; all flowers of the triad sessile
Back to 7 | Amyema lucasii |
| 9 | Rays of the umbel 2 or 3 | 10 |
| Rays of the umbel 3–5
Back to 7 | 12 |
| 10 | Corolla less than 10 mm long | Amyema gaudichaudii |
| Corolla more than 10 mm long
Back to 9 | 11 |
| 11 | Corolla glabrous | Amyema miraculosa |
| Corolla shortly and densely tomentose
Back to 10 | Amyema quandang |
| 12 | Stems spreading; lamina less than 10 cm long, apex rounded | Amyema congener |
| Stems pendent; lamina more than 10 cm long, apex acute
Back to 9 | Amyema pendula |
