Inflorescence panicle-like, raceme-like or spike-like, more rarely reduced to a single spike. Spikes 1–many, terete, sessile or peduncled, with few–many spikelets, wholly male, wholly female, or bisexual; involucral bracts leaf-like or occasionally glume-like, sometimes absent. Spikelets unisexual, consisting of a solitary flower, in the axils of the spirally arranged glumes, in some species ( the Uncinia clade) with hook-like tip of rachilla protruding beyond the perigynium (utricle) in the female spikelets. Stamens 3. Gynoecium enclosed in a bottle-shaped prophyll (perigynium or utricle); style 2- or 3-fid, protruding through the small terminal mouth of the perigynium/utricle. Perigynia (utricles) membranous, papery, leathery, or corky, 2-keeled, narrowed to a beak with truncate or 2-fid apex.
The inflorescence structure is complex in this genus. What are here termed spikes and spikelets have in the past often be called, respectively, spikelets and flowers. Note: glume length includes mucro; perigynium (utricle) length includes the beak (which is described in the terms used by Jermy et al., 1982); leaves are often not obviously septate-nodulose until dried. The axis of the spikelet is conspicuously elongated beyond the apex of the perigynium, ending in a hook that walkers know all too well, in species formerly included in Uncinia. The online key is based on the updated key published in Telopea 6(1): 573-577 (1996), plus correction in Telopea 7(1): 95 (1997) and later updates, including the addition of species formerly in Uncinia. The European species Carex divisa is included in the key but no description is given since it is not known to have become naturalised in NSW. It is, however, naturalised in Vic, Tas, SA and WA so could occur in southern NSW. Various species are being introduced in horticulture and may well become naturalised in more temperate regions. Hybrids seem to be much less common in Australia than in the Northern Hemisphere.
| | Key to the species | |
| 1 | Axis of spikelet protruding with a conspicuous hooked apex beyond the perigynium (utricle) (formerly genus Uncinia) | 41 |
| Axis of spikelet not protruding or hook-like | 2 |
| 2 | Style 3-fid; nut trigonous | 3 |
| Style 2-fid (rarely some styles 3-fid within an inflorescence in Carex gaudichaudiana); nut lenticular or plano-convex
Back to 1 | 17 |
| 3 | Inflorescence of a single spike, less than 1.5 cm long | 4 |
| Spikes several to numerous; inflorescence 3–90 (rarely 1–3) cm long
Back to 2 | 6 |
| 4 | Male part of the spike as long as or longer than the female part and not less conspicuous | Carex capillacea |
| Male part of the spike from slightly to much shorter than the female part, always inconspicuous and usually the spike appears to be wholly female
Back to 3 | 5 |
| 5 | Spike 7–12 mm long, with many female flowers; lowest bract glume-like | Carex cephalotes |
| Spike 4–5 mm long, with about 3–6 female flowers; lowest bract leaf-like, exceeding the spike
Back to 4 | Carex archeri |
| 6 | Spikes in clusters of 2–5 (or occasionally some solitary) at distant nodes | 7 |
| Spikes solitary at nodes (nodes may be close together)
Back to 3 | 9 |
| 7 | Female glumes white with greenish midrib, 1.2–1.5 mm wide | Carex hubbardii |
| 7 | Female glumes pale yellow-brown to red-brown with greenish midrib, 1.5–4 mm wide | 8 |
| 8 | Female glumes yellow-brown to red-brown, 3.5–5.5 mm long, 1.5–2 mm wide; spikes lax-flowered below, rather dense-flowered above, 3–5 mm thick in mature fruiting stage, upper gynaecandrous (sometimes with male apices), uppermost with a long, usually very long, male basal part, the lower gynaecandrous or female | Carex longebrachiata |
| Female glumes pale yellow-brown, 4–8 mm long, 2.5–4 mm wide; spikes dense-flowered, 5–8 mm thick in mature fruiting stage, the uppermost 1–4 wholly male, rarely with a few female flowers in the terminal spike, the remainder wholly female or with male bases and/or apices
Back to 7 | Carex iynx |
| 9 | Perigynia (utricles) hispid; nut with persistent enlarged disk-like junction of nut body and style-base | Carex breviculmis |
| Perigynia glabrous or minutely papillose, sometimes minutely hispid on the margins of the beak; nut without enlarged junction with style-base
Back to 6 | 10 |
| 10 | Perigynia corky, with impressed nerves | 11 |
| Perigynia neither corky nor with impressed nerves
Back to 9 | 12 |
| 11 | Culms extending above the leaf sheaths for a considerable distance; male spikes 3–15; female spikes mostly spread at some distance from one another; female glumes mucronate, dark to very dark red-brown; perigynia 4–5 mm long, yellow-brown usually tinged dark red-brown; leaves with marginal prickles more or less regularly antrorse | Carex bichenoviana |
| Culms usually hidden in the leaf sheaths; male spikes 1–4; female spikes usually approximate; female glumes not mucronate, yellow-brown to red-brown; perigynia 4–8 mm long, yellow-brown occasionally tinged dark red-brown; leaves with marginal prickles irregular and at 90° to leaf
Back to 10 | Carex pumila |
| 12 | Leaves prominently septate-nodulose (septa less obvious when fresh); beak of perigynium with apex deeply divided into 2 stiff slender teeth c. 1 mm long | Carex fascicularis |
| Leaves not septate-nodulose; beak of perigynium with apex truncate, split or shortly divided into 2 membranous, short but broad teeth
Back to 10 | 13 |
| 13 | Male glumes with a mucro as long as or longer than the body of the glume; perigynia glabrous | Carex brownii |
| Male glumes not mucronate or with mucro shorter than the body of the glume; perigynia glabrous, minutely papillose or minutely hispid on margins and beak
Back to 12 | 14 |
| 14 | Perigynia minutely papillose, with beak to 0.3 mm long; leaf sheath and ligule occasionally red-dotted; culms 10–70 cm long | 15 |
| Perigynia not minutely papillose, with beak 0.5–2 mm long; leaf sheath and ligule not red-dotted; culms 1–10 cm long
Back to 13 | 16 |
| 15 | Terminal spike gynaecandrous; leaves shorter than or scarcely exceeding culms; perigynia not or faintly nerved, 3–4.5 mm long | Carex buxbaumii |
| Terminal spike male or at least male in the upppermost portion; leaves much exceeding culms; perigynia strongly numerous-nerved, 2.3–3 mm long
Back to 14 | Carex maculata |
| 16 | Inflorescence 1–3 cm long, hidden amongst leaves; perigynia 4–6.5 mm long, glabrous, with beak 1–2 mm long | Carex jackiana |
| Inflorescence 8–35 cm long, mostly exceeding leaves (lowest spikes may be amongst the leaves); perigynia 3.3–4 mm long, minutely hispid on upper margins (occasionally glabrous), with beak 0.5–0.8 mm long
Back to 14 | Carex blakei |
| 17 | Inflorescence of a single spike | 18 |
| Spikes 2–numerous
Back to 2 | 20 |
| 18 | Plants long-rhizomatous; female bracts 3–4 mm long; perigynium slightly hispidulous on upper margins | 19 |
| Plants short-rhizomatous; female bracts 2.5–3 mm long; perigynium glabrous
Back to 17 | Carex cephalotes |
| 19 | Female flowers above male in spike; perigynia 2.5–3 mm long, weakly several-nerved; culms 25–40 cm long | Carex raleighii |
| Male flowers above female in spike; perigynia 5.5–7 mm long, with 8–10 strong nerves abaxially, adaxially several weak nerves or none; culms 80–160 cm long
Back to 18 | Carex klaphakei |
| 20 | Spikes long-cylindrical (i.e. much longer than broad), mostly 2–17 cm long (rarely some as short as 0.5 cm but then glumes dark red-brown or blackish), clearly distinct and often distant from each other | 21 |
| Spikes ovoid or short-cylindrical (mostly c. 0.5 cm long, occasionally to 1.5 cm long) or ovate in outline, often densely clustered in an inflorescence that is itself ovoid or short-cylindrical
Back to 17 | 25 |
| 21 | At least lower spikes obviously pedicellate, drooping to spreading | 22 |
| Spikes sessile to subsessile ('pedicels' may be up to 1 cm long in C. polyantha), erect to spreading
Back to 20 | 23 |
| 22 | Perigynia white-hispid, with beak c. 1 mm long with 2-fid or split apex; spikes clustered at nodes or rarely solitary at lower nodes | Carex brunnea |
| Perigynia minutely papillose; beak to 0.3 mm long with truncate or obliquely truncate apex; spikes solitary at nodes
Back to 21 | Carex lobolepis |
| 23 | Leaves 4–9 mm wide; spikes mostly 3–17 cm long; perigynia nerveless or with few rather faint nerves | Carex polyantha |
| Leaves 2–4 mm wide; spikes 0.5–6 cm long; perigynia distinctly several- to numerous-nerved
Back to 21 | 24 |
| 24 | Uppermost spike male; inflorescence 7–18 cm long; mouth of perigynium notched to obliquely truncate, pallid, occasionally minutely hispid, 0.2–0.3 mm diam | Carex gaudichaudiana |
| Uppermost spike gynandrous or occasionally male; inflorescence 2–8 cm long; mouth of perigynium truncate, blackish, smooth, c. 0.15 mm diam
Back to 23 | Carex hypandra |
| 25 | All spikes androgynous (male portion often not conspicuous), or upper spike(s) androgynous or male and lower spikes androgynous or occasionally female | 26 |
| All spikes gynaecandrous (male portion often not conspicuous) or lower wholly female
Back to 20 | 35 |
| 26 | Spikes very numerous, forming a long narrow spike-like panicle 6–30 cm long, with appressed secondary branches to 4 cm long; leaves often obviously septate-nodulose; culms 2–4 mm in diameter | 27 |
| Spikes 2–15 in an inflorescence, forming a short clustered panicle 0.8–3 cm long (or an interrupted spike-like panicle in C. divulsa), without secondary branches; leaves not septate-nodulose; culms to 2 mm in diameter
Back to 25 | 30 |
| 27 | Perigynia glabrous, margins not winged | Carex declinata |
| Perigynia hispid on slightly winged margins at least near apex
Back to 26 | 28 |
| 28 | Culms trigonous to triquetrous at least above; glumes uniformly whitish, or yellow-brown without or with very narrow whitish or hyaline margins above | 29 |
| Culms terete; female glumes orange-brown with broad white or hyaline margins above
Back to 27 | Carex tereticaulis |
| 29 | Perigynia with thickened truncate base, dark yellow-brown at maturity; inflorescence often more than 12 cm long (4–45 cm); plants forming large tussocks | Carex appressa |
| Perigynia without thickened truncate base, blackish at maturity; inflorescence 3–12 cm long; culms in slender tufts spread along long rhizome
Back to 28 | Carex incomitata |
| 30 | Inflorescence 6–18 cm long, narrow, with upper spikes contiguous but lower spikes 2–6 cm apart; rhizome short; culms tufted | Carex divulsa |
| Inflorescence 1–8 cm long, pyramidal or ovoid, with spikes mostly close-packed; rhizome long; culms usually solitary and spread out along rhizome
Back to 26 | 31 |
| 31 | Inflorescence 2–8 cm long; perigynia winged | 32 |
| Inflorescence 1–3 cm long; perigynia not winged
Back to 30 | 33 |
| 32 | Female glumes 3.5–4.5 mm long; leaves more or less straight throughout their length | Carex disticha |
| Female glumes 5–6 mm long; leaves curly towards apex
Back to 31 | Carex arenaria |
| 33 | Perigynia 5.5–7 mm long, with obtuse base, abaxial face with 8–10 strong nerves; spikes 1–3; culms 80–160 cm long, relatively soft and flexible (usually supported by surrounding plants) | Carex klaphakei |
| Perigynia 3–4 mm long, with more or less narrow stipe-like base, faces nerveless or with a few faint nerves; spikes 3–12; culms 8–80 cm long, stiffly erect
Back to 31 | 34 |
| 34 | Perigynia 1.8–3.2 mm in diameter, with acute base; leaves 1.5–3 mm wide; rhizome short | Carex divisa |
| Perigynia 1.0–1.2 mm in diameter, with narrow base; leaves to 1.7 mm wide; rhizome long
Back to 33 | Carex chlorantha |
| 35 | Lowest involucral bract much shorter than inflorescence, glume-like or leaf-like | 36 |
| Lowest involucral bract exceeding (usually by far) the whole inflorescence, leaf-like
Back to 25 | 38 |
| 36 | Perigynia winged on upper margins | Carex leporina |
| Perigynia not winged on margins
Back to 35 | 37 |
| 37 | Perigynia strongly reflexed at maturity, with smooth surface; beak about as long as the body of the perigynium, 2-fid or notched with teeth 0.25–0.5 mm long | Carex echinata |
| Perigynia spreading at maturity, minutely hispid and colliculate near apex; beak much shorter than the body of the perigynium, truncate or shortly split abaxially
Back to 36 | Carex canescens |
| 38 | Glumes orange-brown or pale red-brown, with more or less broad whitish or hyaline margins; perigynia never transversely wrinkled | 39 |
| Glumes whitish to pale yellow-brown with green midrib; perigynia often transversely wrinkled at maturity
Back to 35 | 40 |
| 39 | Inflorescence longer in outline than wide; culms 25–40 cm long; leaves c. 1 mm wide; perigynia 2.5–3 mm long, 1–1.4 mm in diameter | Carex raleighii |
| Inflorescence broader in outline than long (or about the same length and breadth); culms 4–20(–35) cm long; leaves 1–2.5 mm wide; perigynia 3.2–4.5 mm long, 1.5–2 mm in diameter
Back to 38 | Carex hebes |
| 40 | Perigynia with beak 0.3–1.1 mm long | Carex inversa |
| Perigynia with beak c. 2 mm long
Back to 38 | Carex lophocarpa |
| 41 | Female glumes persistent; perigynia hispid (formerly Uncinia sinclairii) | Carex parvispica |
| Female glumes deciduous; perigynia glabrous
Back to 1 | 42 |
| 42 | Leaves thickly U-shaped to crescent-shaped in cross section, tough (formerly Uncinia sulcata) | Carex austrosulcata |
| Leaves nearly flat or broadly V-shaped or filiform, more or less soft
Back to 41 | 43 |
| 43 | Inflorescence 3–7 cm long; spikelets more or less spread out along axis (basal internodes 5–12 mm long); fibrous bases to more or less large tussocks | 44 |
| Inflorescence 0.7–3 cm long; spikelets more or less crowded on axis (may be more spread out towards base but internodes no more than c. 4 mm long); small tussocks (bases not fibrous) or culms spread out along rhizomes
Back to 42 | 45 |
| 44 | Leaves 1.5–2.2 mm wide; nut 2.5–3 mm long, 0.8–1.3 mm diam.; hooked rachilla protruding from perigynium for 4–6.5 mm (formerly Uncinia nemoralis) | Carex nemoralis |
| Leaves 0.5–1.0 mm wide; nut c. 2.2 mm long, c. 0.7 mm diam.; hooked rachilla protruding from perigynium for 3.5–4 mm (formerly Uncinia debilior)
Back to 43 | Carex debilior |
| 45 | Leaves 2–3.5 mm wide; culms usually scabrous below inflorescence, 0.8–1.1 mm diam. (formerly Uncinia compacta) | Carex austrocompacta |
| Leaves 0.5–1.8 mm wide; culms mostly smooth below inflorescence, 0.2–0.7 mm diam.
Back to 43 | 46 |
| 46 | Stamens 3; inflorescence 1.5–2.5(–3) cm long; perigynia 1.5–1.8 mm diam.; leaves shorter than culms, 0.8–1.8 mm wide; culms 0.3–0.7 mm diam. (formerly Uncinia flaccida) | Carex flaccida |
| Stamens 2; inflorescence 0.7–1.5 cm long; perigynia 0.8–1 mm diam.; leaves exceeding or equalling culms, 0.5–1 mm wide; culms 0.2–0.4 mm diam. (formerly Uncinia tenella)
Back to 45 | Carex austrotenella |
