Leaves alternate, flat, ± covered with vesicular hairs; the hairs burst when the leaf is still young, resulting in a glistening mealy indumentum.
Flowers either in terminal paniculate or spicate inflorescences or in axillary clusters, unisexual. Male flowers 5-merous, the 5 perianth segments usually covered with vesicular hairs. Female flowers without a perianth, consisting of 2 variously fused or free bracteoles with or without dorsal appendages.
Pericarp membranous, style branches 2, seed laterally compressed, mostly vertical.
| | Key to the species | |
| 1 | Long-lived perennial shrubs; frequently dioecious | 4 |
| Annuals or short-lived perennials; monoecious | 2 |
| 2 | Fruiting bracteoles fused for less than half their length | 12 |
| Fruiting bracteoles fused for more than half their length
Back to 1 | 3 |
| 3 | Fruiting bracteoles with dorsal appendage(s) | 25 |
| Fruiting bracteoles without dorsal appendages
Back to 2 | 35 |
| 4 | Mostly dioecious, though some mixing of sexes may occur; woody perennials | 5 |
| Plants usually monoecious; woody or herbaceous perennials
Back to 1 | 10 |
| 5 | Shrub 1.5–3 m high, inland species only | 6 |
| Shrubs to c. 1 m high, inland and coastal species
Back to 4 | 7 |
| 6 | Foliage and stems with a bluish grey scaly sheen on all surfaces; bracteoles thickened and corky all over | Atriplex rhagodioides |
| Foliage and stems grey-green,bracteoles thin and papery toward apical margin
Back to 5 | Atriplex nummularia |
| 7 | Coastal species; fruiting bracteoles obtuse to acute, united to just below the middle, sometimes with a small base, lower central portion swollen or not | Atriplex cinerea |
| Inland species; fruiting bracteoles with or without appendages, obtuse or acute, sessile or with a long stipe-like base
Back to 5 | 8 |
| 8 | Delicate erect shrub to c. 1 m high; fruiting bracteoles with a stipe-like base more than 3 mm long | Atriplex stipitata |
| Robust or spreading shrubs to c. 1 m high; fruiting bracteoles virtually sessile
Back to 7 | 9 |
| 9 | Fruiting bracteoles with entire margins and usually with an appendage; appendage sometimes inflated and almost as long as the bracteole or reduced | Atriplex vesicaria |
| Fruiting bracteoles lobed and without appendages
Back to 8 | Atriplex sp. B sensu Jacobs (1990) |
| 10 | Fruiting bracteoles sessile or subsessile, more or less triangular, occasionally with spiny appendages | Atriplex velutinella |
| Fruiting bracteoles with an obvious stipe-like base; apex expanded, more or less fan-like; bracteoles with or without appendages
Back to 4 | 11 |
| 11 | Fruiting bracteoles without dorsal appendages | Atriplex stipitata |
| Fruiting bracteoles with a reniform dorsal appendage
Back to 10 | Atriplex quinii |
| 12 | Fruiting bracteoles with dorsal appendage(s) | 13 |
| Fruiting bracteoles without dorsal appendages
Back to 2 | 20 |
| 13 | Fruiting bracteoles with entire margins or 3-lobed but otherwise entire | 14 |
| Margins of fruiting bracteoles with more than 3 teeth
Back to 12 | 18 |
| 14 | Fruiting bracteoles more than 6 mm long | 15 |
| Fruiting bracteoles less than 6 mm long
Back to 13 | 16 |
| 15 | Fruiting bracteoles sessile or subsessile, more or less triangular | Atriplex velutinella |
| Fruiting bracteoles with a hardened stipe-like base
Back to 14 | Atriplex acutibractea |
| 16 | Fruiting bracteoles both with numerous papillate appendages | Atriplex papillata |
| Fruiting bracteoles at most with two small tooth-like appendages on one or both bracteoles
Back to 14 | 17 |
| 17 | Fruiting bracteoles broader than long | Atriplex acutiloba |
| Fruiting bracteoles longer than broad or as long as broad
Back to 16 | Atriplex semibaccata |
| 18 | Bracteole teeth usually 5 | Atriplex acutiloba |
| Bracteole teeth more than 5
Back to 13 | 19 |
| 19 | Fruiting bracteoles sessile, leaves elliptic or broad- elliptic to obovate | Atriplex fissivalvis |
| Fruiting bracteoles with stipe-like base 0.5–1.5 mm long, leaves lanceolate to narrow-obovate
Back to 18 | Atriplex spinibractea |
| 20 | Margins of fruiting bracteoles with more than 3 teeth | Atriplex spinibractea |
| Margins of fruiting bracteoles entire or 3-lobed
Back to 12 | 21 |
| 21 | Fruiting bracteoles rhombic, apex triangular | 22 |
| Fruiting bracteoles broad-triangular
Back to 20 | 23 |
| 22 | Plant prostrate; fruit solitary or few together, axillary | Atriplex semibaccata |
| Plant erect; fruit in dense clusters in terminal spike-like inflorescences
Back to 21 | Atriplex patula |
| 23 | Inland short-lived perennial; leaves ovate or rhombic; fruiting bracteoles 6–9 mm long | Atriplex velutinella |
| Coastal annuals (rarely short-lived perennials); leaves hastate or ovate; fruiting bracteoles less than 6 mm long
Back to 21 | 24 |
| 24 | Plant decumbent; leaves and fruit glaucous; inflorescence usually c. 20–30% of plant | Atriplex australasica |
| Plant erect; leaves green, fruit dark green; inflorescence usually c. 50% of plant
Back to 23 | Atriplex prostrata |
| 25 | Fruiting bracteoles with a stipe-like base more than 1 mm long | 26 |
| Fruiting bracteoles sessile or with a stipe-like base less than 1 mm long
Back to 3 | 30 |
| 26 | Fruiting bracteoles broadest c. midway up | Atriplex spinibractea |
| Fruiting bracteoles broadest at the top
Back to 25 | 27 |
| 27 | Dorsal appendages larger than the free portion of the bracteole | Atriplex limbata |
| Dorsal appendages smaller than the free portion of the bracteole
Back to 26 | 28 |
| 28 | Appendages reniform, 1 on each bracteole | Atriplex quinii |
| Appendages tooth-like, 1 or 2 on one bracteole only
Back to 27 | 29 |
| 29 | Leaves petiolate, spreading; appendages 2 on one bracteole | Atriplex eardleyae |
| Leaves sessile, erect; appendages 1 or 2 on one bracteole or absent
Back to 28 | Atriplex pseudocampanulata |
| 30 | Fruiting bracteoles less than 3 mm long | 31 |
| Fruiting bracteoles more than 3 mm long
Back to 25 | 32 |
| 31 | Apex of fruiting bracteoles acute | Atriplex infrequens |
| Apex of fruiting bracteoles truncate
Back to 30 | Atriplex elachophylla |
| 32 | Dorsal appendages large, inflated | 33 |
| Appendages small, tooth-like
Back to 30 | 34 |
| 33 | Central lobe of apex longer than the two lateral lobes, c. as long as the inflated base | Atriplex nessorhina |
| All 3 terminal lobes more or less equal, much shorter than the inflated appendage
Back to 32 | Atriplex morrisii |
| 34 | Fruiting bracteoles broadest at the base, broad-triangular | Atriplex acutiloba |
| Fruiting bracteoles broadest around the middle, rhombic
Back to 32 | Atriplex semibaccata |
| 35 | Fruiting bracteoles spongy, inflated | 36 |
| Fruiting bracteoles neither spongy nor inflated
Back to 3 | 38 |
| 36 | Apex of bracteoles flattened, with wing-like margins | Atriplex lindleyi |
| Apex of bracteoles rounded, no wing-like margins
Back to 35 | 37 |
| 37 | Leaves sessile | Atriplex spongiosa |
| Leaves petiolate
Back to 36 | Atriplex holocarpa |
| 38 | Fruiting bracteoles with hardened stipe-like base | 39 |
| Fruiting bracteoles sessile or shortly stalked, sometimes hardened but without an obvious hardened stipe-like base
Back to 35 | 46 |
| 39 | Fruiting bracteoles at least twice as broad at apex as elsewhere | 40 |
| Fruiting bracteoles cylindrical or broadest at the middle
Back to 38 | 44 |
| 40 | Fruiting bracteoles more than 6 mm long | 41 |
| Fruiting bracteoles less than 6 mm long
Back to 39 | 43 |
| 41 | Fruiting bracteoles almost as broad as long (about two-thirds as broad as long), upper free portion of bracteoles usually with recurved lobes (rarely the lobes reduced) | Atriplex angulata |
| Fruiting bracteoles about half as broad as long, upper portion of bracteoles fan-shaped
Back to 40 | 42 |
| 42 | Stipe-like base of fruiting bracteoles swollen and hardened | Atriplex intermedia |
| Stipe-like base of fruiting bracteoles hardened but not swollen
Back to 41 | Atriplex turbinata |
| 43 | Fruiting bracteoles 3.5 mm long or less | Atriplex crassipes |
| Fruiting bracteoles more than 3.5 mm long
Back to 40 | Atriplex pseudocampanulata |
| 44 | Fruiting bracteoles broadest at the middle | Atriplex spinibractea |
| Fruiting bracteoles more or less cylindrical
Back to 39 | 45 |
| 45 | Fruiting bracteoles less than 4 mm long; leaves obovate, to 15 mm long | Atriplex sturtii |
| Fruiting bracteoles more than 4 mm long; leaves oblong to linear-lanceolate, may be more than 15 mm long
Back to 44 | Atriplex leptocarpa |
| 46 | Fruiting bracteoles spreading at the apex to form a broad, terminal, more or less flat wing more than 5 mm diam | Atriplex macropterocarpa |
| Fruiting bracteoles various but not forming a broad, flat, terminal wing
Back to 38 | 47 |
| 47 | Fruiting bracteoles less than 3 mm long | 48 |
| Fruiting bracteoles more than 3 mm long
Back to 46 | 51 |
| 48 | Fruiting bracteoles acute with a central acute lobe, lateral lobes present or absent | 49 |
| Fruiting bracteoles more or less truncate; lobes, if present, more or less equal
Back to 47 | 50 |
| 49 | Fruiting bracteoles with lateral lobes and with a vertical thickened zone | Atriplex lobativalvis |
| Fruiting bracteoles rhombic, without lateral lobes, not obviously thickened
Back to 48 | Atriplex infrequens |
| 50 | Fruiting bracteoles not obviously thickened, tapering gradually into the truncate, unlobed to 3-lobed apex | Atriplex pumilio |
| Fruiting bracteoles with swollen, hardened base surmounted by a small lobed apex
Back to 48 | Atriplex elachophylla |
| 51 | Fruiting bracteoles more than 8 mm long, flattened dorsiventrally | Atriplex lindleyi |
| Fruiting bracteoles less than 6 mm long, more or less swollen
Back to 47 | 52 |
| 52 | Fruiting bracteoles more or less rhombic, no obviously thickened zone, though sometimes succulent and red | Atriplex semibaccata |
| Fruiting bracteoles with a globose thickened zone surmounted by a lobed apex
Back to 51 | 53 |
| 53 | Apex of fruiting bracteoles obtuse, all teeth more or less equal in length; leaf apex obtuse | Atriplex muelleri |
| Apex of fruiting bracteoles acute, with one tooth more prominent; leaf apex acute to obtuse
Back to 52 | Atriplex suberecta |
