2 (1)	Phyllodes either absent (occasional twigs.rarely with a few articulate phyllodes), or continuous with the branches	Goto 3
(2)	Phyllodes present and articulate on the branches	Goto 4

3 (1)	Phyllodes normally absent, if present then articulate on branch; flowers 3-8 per head	A. spinescens
(2)	Phyllodes present, continuous with branch; flowers c. 30 per head	A. continua

4 (1)	Phyllodes innocuous.	Goto 5
(2)	Phyllodes pungent-pointed.	Goto 28

5 (1)	Phyllodes to 2 cm long.	Goto 6
(2)	Phyllodes 2-12 cm long.	Goto 16

6 (1)	Branchlets spinescent.	Goto 7
(2)	Branchlets not spinescent.	Goto 8

7 (1)	Branchlets hairy; phyllodes n .arrow-cuneate, humped at the summit	A. acanthoclada
(2)	Branchlets glabrous; phyllodes broadly lanceolate, never humped	A. erinacea

8 (1)	Stipules prominent and spiny	A. paradoxa
(2)	Stipules when present minute and not spiny.	Goto 9

9 (1)	Shrubs prominently resinous; phyllodes viscid.	Goto 10
(2)	Shrubs not or sometimes very slightly resinous; phyllodes not viscid, 5-20 mm long.	Goto 11

10 (1)	Phyllodes fiat, obliquely obovate, 2-5 mm long	A. rhetinocarpa
(2)	Phyllodes terete-compressed, 1-2 cm long	A. helmsiana

11 (1)	Phyllodes ovate-oblanceolate to obovate-orbicular.	Goto 12
(2)	Phyllodes linear or oblong.	Goto 14

12 (1)	Phyllodes grey-green, heads 20-30 flowered.	Goto 13
(2)	Phyllodes mid-green; heads 10-15-flowered; peduncles often longer than phyllodes; legumes spirally coiled	A. acinacea

13 (1)	Peduncles mostly longer than phyllodes, heads 8-10 mm diam	A. spilleriana
(2)	Peduncles mostly shorter than phyllodes, heads about 5 mm diam	A. brachybotrya

14 (1)	Branchlets pubescent, almost terete; phyllodes with the vein ~ close to the lower margin	A. lineata
(2)	Branchlets glabrous, angular.	Goto 15

15 (1)	Phyllodes erect, imbricate; apex almost truncate except for an oblique mucro	A. imbricata
(2)	Phyllodes spreading-erect, not imbricate, apex obtuse	A. triquetra

16 (1)	Branchlets acutely angular, often compressed and winged.	Goto 17
(2)	Branchlets angular or striate, becoming almost terete, never flattened or winged.	Goto 19

17 (1)	Phyllodes with obviously reticulate lateral veins; peduncles stout, solitary; heads c. 40-flowered; seeds transversely placed in the legume.	Goto 18
(2)	Phyllodes without reticulate lateral veins; peduncles slender, 2-4 (rarely 1) per axil; heads 12-20-flowered; seeds longitudinally placed in the legume	A. triquetra

18 (1)	Phyllodes often glaucous, broadly ovate, 10-35 mm broad, up to twice as long as broad	A. anceps var. anceps
(2)	Phyllodes never glaucous, linear-oblong, oblanceolate, 5-13 mm broad, 5-12 times longer than broad	A. anceps var. angustifolia

19 (1)	Branchlets and phyllodes pubescent or becoming glabrous when mature.	Goto 20
(2)	Branchlets and phyllodes glabrous (young phyllodes minutely pubescent in A. microcarpa).	Goto 22

20 (1)	Phyllodes always hairy, golden pubescent when young, silky-silvery with more or less appressed hairs when mature, flower-heads mostly shorter than phyllode, longer if common peduncle well developed	A. argyrophylla
(2)	Phyllodes silky grey hairy when young, becoming glabrous with age.	Goto 21

21 (1)	Peduncle mostly shorter than phyllode, heads about 5 mm diam	A. brachybotrya
(2)	Peduncles mostly longer than leaf, heads 8-10 mm diam	A. spilleriana

22 (1)	Phyllodes terete or if flattened then not exceeding 5 mm broad; apex always uncinate.	Goto 23
(2)	Phyllodes distinctly flattened, 5-15 mm broad; apex sometimes mucronate, never distinctly uncinate.	Goto 25

23 (1)	Apex always acute or acuminate.	24
(2)	Apex always blunt with two glands at summit, phyllodes often slightly upcurved	A. praemorsa

24 (1)	Peduncle in axillary racemes commonly 1-4 mm long with 2-4 peduncles rarely greater, rarely solitary	A. calamifolia
(2)	Peduncles almost always solitary	A. nematophylla

25 (1)	Branchlets and young phyllodes viscid; phyllodes punctate, apex acute, with up to 4 glands along the upper margin	A. dodonaeifolia
(2)	Branchlets and phyllodes not viscid, or phyllodes not punctate, apex obtuse, only 1 gland along the upper margin.	Goto 26

26 (1)	Phyllodes 5-12 cm long, apex mostly obtuse, mid-vein prominent and many fine lateral veins, peduncles < 5 mm	A. stricta
(2)	Phyllodes to 5 cm long, apex acute or obtuse, mid-vein often obscure, peduncles > 5 mm.	Goto 27

27 (1)	Phyllode apex obtuse, phyllodes straight or with slight upward cur~e, young tips + glabrous	A. microcarpa
(2)	Phyllode apex acute, phyllodes slightly recurved, young tips densely pubescent (later glabrous)	A. halliana

28 (1)	Stipules prominent and spiny.	Goto 29
(2)	Stipules when present small and not spiny.	Goto 30

29 (1)	Phyllodes flat, glabrous, rhomboid-orbicular, 1-2 cm long	A. strongylophylla
(2)	Phyllodes terete, minutely pubescent, 3-6 cm long	A. pickardii

30 (1)	Phyllodes humped on the upper margin.	Goto 31
(2)	Phyllodes not humped on the upper margin.	Goto 32

31 (1)	1 prominent vein parallel to and near the lower margin; heads whitish-yellow, 20-30-flowered; legumes straight or curved	A. gunnii
(2)	1 prominent oblique vein with 2-4 rather obscure veins arising from near the base; heads golden-yellow, 8-15-flowered; legumes spirally coiled	A. pravifolia

32 (1)	Phyllodes flat, obliquely ovate-orbicular or obovate, 5-15 mm broad, up to twice as long as broad	A. merrallii
(2)	Phyllodes flat or angular, linear-subulate or linear-lanceolate or narrow-elliptic, 1-5 mm broad, more than twice as long as broad.	Goto 33

33 (1)	Branchlets resinous; phyllodes viscid (at least when young), 1-2.5 cm long.	Goto 34
(2)	Branchlets not resinous; phyllodes not viscid, 2-6 cm long.	Goto 35

34 (1)	Heads c. 20-flowered, creamy-yellow; phyllodes spreading horizontally, broadest at or near the base, viscid	A. rupicola
(2)	Heads 50-60-flowered, mid-yellow; phyllodes erect or spreading, broadest near the centre, slightly viscid	A. maitlandii

35 (1)	Phyllodes pubescent	A. carnei
(2)	Phyllodes glabrous (at least with age).	Goto 36

36 (1)	Phyllodes usually clustered in groups 2-5, heads c. 50flowered	A. tetragonophylla
(2)	Phyllodes scattered, not clustered, heads less than c. 20 flowered.	Goto 37

37 (1)	Heads creamy yellow; phyllodes at right angles to branch, apex tapered	A. genistifolia
(2)	Heads golden yellow; phyllodes ascending, apex abruptly pungent	A. mutabilis

38 (1)	Inflorescences simple, solitary or 2-3 together	Goto 39
(2)	Inflorescence racemose or paniculate	Goto 40

39 (1)	Stipules prominent, spiny; pinnules 10-21 pairs	A. farnesiana
(2)	Stipules minute, not spiny, pinnules 2-7 pairs	A. mitchellii

40 (1)	Branches prominently angled with wing-like ridges	A. decurrens
(2)	Branches angled or striate but not winged	Goto 41

41 (1)	Leaves with 2-6 pairs of pinnae	A. baileyana
(2)	Leaves with 10-26 pairs of pinnae	Goto 42

42 (1)	Leaf rhachis with a gland at the junction of each pinna pair and with additional glands between the pinna pairs	A. mearnsii
(2)	Leaf rhachis with a gland at the junction of each pinna pair, without additional glands between	A. dealbata