1. Inflorescence an umbel of triads or tetrads
2
1. Inflorescence other than an umbel of triads or tetrads (e.g.
a head, simple umbel or solitary flower) 23
2.. Flowers in triads 3
2. Flowers in tetrads 21
3. Triads with all flowers sessile 4
3. Triads with at least the lateral flowels pedicellate 10
4. Leaves regularly opposite 5
4. Leaves in whorls of 3-8 (sometimes scattered) 7
5. Leaves sessile and cordate at the base 7. A. cercidioides
5. Leaves petiolate 6
6. Lamina mostly acute and acuminate at the apex, mostly more
than 8 cm long 14. A.
friesianum
6. Lamina rounded at the apex, less than 8 cm long 20. A. obovatum
7. Stems triangular below the nodes
when young 2. A.
angulare
7. Stems terete even when
young 8
8. Lamina less than 1 cm wide, channelled above 6. A. canaliculatam
8. Lamina more than 1 cm
wide, flat 9
9. Lamina almost orbicular, up to 8 cm long 22. A. pentactis
9. Lamina lanceolate to ovate,
more than 8 cm long 23.
A. scandens
10. Rays in the umbel mostly two
11
10. Rays in the umbel three or more 12
11. Runners present. Pedicels of the lateral flowers usually more
than 1 mm long. Rays of the umbel 3-6 mm long 4. A. artense
11. Runners absent. Pedicels of
the lateral flowers c. 0.5 mm long. Rays of the umbel 1.5-2.5
mm long 9. A. conspicuum
12. Corolla mostly 4-merous 13
12. Corolla 5- or 6-merous 17
13. Rays of the umbel 3-4-(5) 14
13. Rays of the umbel 5-12 29.
A. wichmannii
14. Lamina acuminate and acute
at the apex, mostly less than 1 cm wide 17. A. kebarense
14. Lamina rounded at the apex
(sometimes with a small mucro), mostly more than 1 cm wide.. 15
15. Peduncle slender (up to 1 mm thick), more than 12 mm long.
Internodes slender, not strongly articulate at the nodes 16
15. Peduncle 11.5 mm thick, less than 12 mm long. Internodes mostly
less than 3 cm long, strongly articulate at the nodes 21. A. pachypus
16. Lamina ovate to orbicular,
less than 4 cm long. Peduncle more than 18 mm long 10. A. corniculatum
16. Lamina elliptical to ovate, more than 4 cm long. Peduncle
mostly less than 18 cm long 8.
A. clavipes
17. Leaves quaternate 1.
A. aneityense
17. Leaves opposite 18
18. Rays in the umbel 7-20 26.
A. strongylophyllum
18. Rays in the umbel 3-6 19
19. Corolla about 30 mm long. Bracts of the lateral flowers of
the triads rounded, concave, enclosing the calyx 16. A. involvens
19. Corolla up to 20 mm long. Bracts of the lateral flowers of
the triads acute, not enclosing the calyx 20
20. Runners absent. Lamina 25-4cm long, rounded at the apex. Rays
usually 3. 18. A.
mackayense
20. Runners present. Lamina 4-8 cm long, mostly acute at the apex.
Rays 4-6. 19. A.
novae-brittanniae
21. Corolla 4-merous, choripetalous 12. A. dilatipes
21. Corolla 6-merous, gamopetalous in the lower part 22
22. Tetrads with all flowers sessile 27. A. tetraflorum
22. Tetrads with three flowers shortly pedicellate 5. A. brassii
23. Inflorescence a 6-flowered head with an involucre of 2 enlarged
bracts. 28. A. tetrapetalum
23. Inflorescence a simple umbel 24
23. Inflorescence a solitary flower on an articulate peduncle
26
24. Rays of the umbel 3. Leaves scattered-ternate 3. A. apodum
24. Rays of the umbel 2. Leaves opposite 25
25. Peduncle 3-8 mm long 24.
A. seemenianum
25. Peduncle up to 1 mm long 25.
A. squarrosum
26. Corolla 6-merous, gamopetalous 11. A. curvifolium
26. Corolla 4-merous, choripetalous 27
27. Leaves 4-7 cm long, acuminate, acute, almost sessile. Peduncle
alticulate, c. 3 mm long 15.
A. hastifolium
27. Leaves mostly 1.8-4 cm long, rounded, distinctly petitiolate.
Peduncle articulate, 4-8 mm long 13. A. finisterrae
Amyema key
updated 27 May 2002