Inflorescence paniculate or cymose, though frequently reduced to solitary axillary flowers. Flowers bisexual or unisexual, with a single perianth whorl. Perianth of 1–5 segments, often variously fused, rarely absent, frequently developing spines, wings or tubercles in fruit. Stamens opposite and equal to, or fewer than, perianth segments. Ovary usually superior (half-inferior in Beta), 1-locular; stigmas 2 or 3.
| | Key to the genera | |
| 1 | Plants with obvious leaves, mostly alternate; branches not articulated | 2 |
| Plants with opposite very reduced leaves or apparently leafless; younger branch internodes swollen and succulent, photosynthetic, apparently articulated (samphires) | 22 |
| 2 | Ovary half-inferior; fruiting perianths united in clusters; introduced species in coastal areas | Beta |
| Ovary superior; fruiting perianths free or variously fused; native and introduced species of various habitats
Back to 1 | 3 |
| 3 | Fruiting perianth fused and succulent, frequently red, yellow or puce | Enchylaena |
| Fruiting perianth various but never succulent and berry-like
Back to 2 | 4 |
| 4 | Flowers free from one another and fruiting perianth not or little changed from perianth at early flowering stages | 5 |
| Either flowers variously fused and/or fruiting perianth hardened or with various wings, spines or other modifications developing from early flowering stages (very occasionally these failing to develop in some individuals), or perianth absent and fruit subtended by modified bracteoles
Back to 3 | 13 |
| 5 | Herbs | 6 |
| Shrubs
Back to 4 | 10 |
| 6 | Herb with basal rosette of leaves; perianth segments 4, cartilaginous in fruit | Scleroblitum |
| Herbs without basal rosette; perianth segments 1–5, remaining unaltered in fruit
Back to 5 | 7 |
| 7 | Glandular-pubescent herbs; perianth segments 1–4; stamens 1 or 2 | Dysphania |
| Either plants not glandular-pubescent or perianth segments 5; stamens 1–5
Back to 6 | 8 |
| 8 | Leaves semiterete; hairs, if present, simple; embryo spirally coiled | Suaeda |
| Leaves flattened; hairs glandular or vesicular (mealy); embryo in one plane
Back to 7 | 9 |
| 9 | Perianth segments 5; stamens 1–3 only in terminal (on branches) bisexual flowers, lateral flowers female; fruit occasionally with inflated succulent pericarp | Einadia |
| Perianth segments 3–5; stamens 1–5; flowers mostly bisexual but some species with terminal (on branches) bisexual flowers and lateral female flowers; fruit only rarely (Chenopodium curvispicatum) with inflated succulent pericarp
Back to 8 | Chenopodium |
| 10 | Leaves semiterete; hairs, if present, simple; embryo spirally coiled | Suaeda |
| Leaves flattened; hairs vesicular (mealy); embryo in one plane
Back to 5 | 11 |
| 11 | Plants shrubby, mainly dioecious; stamens 5; fruit with inflated succulent pericarp | Rhagodia |
| Plants herbaceous or shrubby, mainly monoecious though flowers frequently bisexual; stamens 1–5; pericarp inflated and succulent or not
Back to 10 | 12 |
| 12 | Perianth segments 5; stamens 1–3 only in terminal (on branches) bisexual flowers, lateral flowers female; fruit occasionally with inflated succulent pericarp | Einadia |
| Perianth segments 3–5; stamens 1–5; flowers mostly bisexual but some species with terminal (on branches) bisexual flowers and lateral female flowers; fruit rarely (Chenopodium curvispicatum) with inflated succulent pericarp
Back to 11 | Chenopodium |
| 13 | Flowers mostly unisexual, the female flowers lacking a perianth but subtended by a pair of bracteoles that are variously free, fused or ornamented | Atriplex |
| Flowers bisexual or unisexual, all flowers with a perianth but this often much modified in fruit
Back to 4 | 14 |
| 14 | Flowers fused in clusters of 2 or more | Dissocarpus |
| Flowers free
Back to 13 | 15 |
| 15 | Fruiting perianth without appendages; cartilaginous to hardened | 16 |
| Fruiting perianth with various appendages
Back to 14 | 17 |
| 16 | Herbs with a basal rosette of leaves; fruiting perianth cartilaginous; perianth segments 4 | Scleroblitum |
| Small woody perennials without a basal rosette of leaves; fruiting perianth hardened; perianth usually 5-lobed or rarely 3- or 4-lobed
Back to 15 | Threlkeldia |
| 17 | Fruiting perianth spinescent or with other cylindrical outgrowths joined by wings or free | 18 |
| Fruiting perianth with various wings, not spinescent
Back to 15 | 20 |
| 18 | Fruiting perianth with 3–5 more or less cylindrical, soft appendages | Malacocera |
| Fruiting perianth spinescent
Back to 17 | 19 |
| 19 | Fruiting perianth cylindrical with 5 spines arising from base of perianth lobes, the spines united into an apical cup-shaped structure | Neobassia |
| Fruiting perianth variously shaped with 1–6 (sometimes 8–15) spines or tubercles arising between the perianth lobes
Back to 18 | Sclerolaena |
| 20 | Wings on fruiting perianth vertical | Osteocarpum |
| At least some wings on fruiting perianth horizontal
Back to 17 | 21 |
| 21 | Flowers subtended by a pair of prominent spinescent bracteoles; embryo spirally coiled | Salsola |
| Floral bracts absent or minute, never spinescent; embryo in one plane
Back to 20 | Maireana |
| 22 | Axillary inflorescences 5–9-flowered; plants spreading; stamens 2; perisperm absent | Sarcocornia |
| Axillary inflorescences 3-flowered; plants more or less low hemispherical shrubs; stamen 1; perisperm present
Back to 1 | Tecticornia |
