Cyperus mundii (Nees) Kunth

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation

Predicted extinction risk: not threatened. Confidence: confident

J. Browning, K.D. Gordon-Gray†, M. Lock, H. Beentje, K. Vollesen, K. Bauters, C. Archer, I. Larridon, M. Xanthos, P. Vorster, J. Bruhl, K. Wilson and X. Zhang (2020). Flora Zambesiaca Volume: 14: Cyperaceae. M.Á. García, J.R. Timberlake (Eds). Kew Publish

Type

South Africa, W Cape, Zwellendam, George, n.d., Mund s.n. (B holotype, S), see note.

Morphology General Habit

Stoloniferous perennial; stolons to 1 m long, 2–5 mm thick, rooting at nodes, each ending in a single ascending to erect culm to 75 cm long, basal part of culm covered in inflated leaf sheaths, to 8 mm wide; stems above leaves 0.5–2 mm wide, triangular, grooved

Morphology Leaves

Leaves spread along culm, stiff to almost prickly, sheaths to 4.5 cm long, greenish to yellowish brown, opposite blade with a brown to red or purple hyaline ochre which eventually splits into two flanges; blade flat, to 17(25) cm long and 1.5–7(8) mm wide, minutely scabrid near tip

Morphology Reproductive morphology Inflorescences

Inflorescence 1–6(8) × (1)2–10(12) cm, a compound umbel-like anthela with 1–3 subsessile and (1)2–9 stalked clusters, rarely all clusters subsessile; peduncles of stalked clusters 0.5–5(7) cm; spikelets in dense digitate ovoid clusters, each cluster with 2–10(15) spikelets; involucral bracts leaf like, 2–5, largest 2–10 cm long, 1–6 mm wide, scabrid near apex

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets 4–12 × 2–4 mm, linear-lanceolate to ovate; rachis straight in fruiting stage; glumes appressed at first, only slightly spreading from flowering stage, tardily dehiscent at maturity, pale brown to reddish brown or dark brown, broadly ovate, with a broad upcurved margin making the central area appear as a large groove, 1.5–3 × 1–2 mm, obtuse, keel brown

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens 2–3; filaments 2–3 mm long; anthers 1–2 mm long

Morphology Reproductive morphology Flowers Gynoecium Stigma

Stigma branches 2, 2–6 mm long

Morphology Reproductive morphology Fruits

Nutlet oblong to obovoid, tapering to truncate, apiculate, grey to greyish brown, 0.5–1 mm long, almost smooth to minutely papillose or finely muricate.

Distribution

Botswana, Zambia, Zimbabwe, Malawi, Mozambique. Widespread in Tropical and South Africa and Madagascar; also in Egypt, Spain and Brazil.

Ecology

Swamps, lakeshores, wet grassland, frequently forming floating mats, also on seashores; 0–1900 m.

Conservation

Widespread distribution; Least Concern. In common and widespread habitats.

Recognition

Often forming thick floating swards around waterholes and along streams. The notes on Richards 14832 (Botswana, Okavango, Toakhe R. swamp) says “...thick floating mass... so thick one can walk on it”.

Cyperaceae, K Hoenselaar, B. Verdcourt & H. Beentje. Hypolytrum, D Simpson. Fuirena, M Muasya. Flora of Tropical East Africa. 2010

Type

Type: South Africa, Zwellendam W George, Mundt s.n. (B, holo.)

Morphology General Habit

Perennial up to 35 cm high, with stolons up to 2 m long.

Morphology Stem

Rooting copiously at each node and ending in an inflorescence.

Morphology Culms

Culm trigonous, smooth, sometimes ± grooved, the non-bearing leaf part 3–29 cm long, 0.7–2.5(–5) mm wide

Morphology Leaves

Leaves up to 21 cm long, spread along the flowering culm. Leaf sheath yellow-brown, sometimes greenish, often with a red-purple coloured triangle at the side opposite the leaf, 1–4(–7) cm long. Leaf blade (narrowly) linear, ± plicate, 2.2–16.5 cm long, 1–5.5(–7.2) mm wide, acute to acuminate, the apex often ± minutely scabrid

Morphology Reproductive morphology Inflorescences Bracts

Involucral bracts leaf-like, 2–6, spreading, lowermost 1.8–10.5 cm long, 1–4.8 mm wide, apex almost glabrous to ± scabrid

Morphology Reproductive morphology Inflorescences

Inflorescence capitate or simple, when simple primary branches (0–)2–12, (0–)0.5–6.5 cm long.

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets 2–13 per cluster, ovoid-lanceolate to (broadly) ovoid, flattened or sometimes almost conical, the glumes loosely to densely compressed, 1.3–11.5 mm long, 1–4 mm wide, axis straight. Spikelets crowded in digitate, ovoid clusters, sometimes on slightly elongated axis, sessile and at the end of primary branches.

Morphology Reproductive morphology Inflorescences Bracts Glume

Glumes from almost yellow to (pale) brown to black, ovate, 1.8–2.6 mm long, 1.1–2.2 mm wide, keel acute to rather broad, furrowed on both sides of the keel, not always distinct, 0–3-veined, apex obtuse to almost acute

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens 2–3.

Morphology Reproductive morphology Flowers Androecium Stamens Filaments

Filaments 2–3.1 mm long.

Morphology Reproductive morphology Flowers Androecium Stamens Anthers

Anthers 0.7–1.7 mm long

Morphology Reproductive morphology Flowers Gynoecium Stigma

Stigma 2-branched

Morphology Reproductive morphology Fruits

Nutlet dark (greyish-)brown, obovoid, sometimes almost oblong, biconvex, 0.7–1.1 mm long, 0.4–0.6 mm wide, almost glabrous to minutely papillose to somewhat wrinkled

Figures

Fig. 43, p285

Note

Although this species is easily recognizable, it is also very variable. The habit can range from very delicate stolons, leaves and culms to more robust ones; the inflorescence can also vary between specimens, e.g. capitate or simple inflorescences, and the number and length of primary branches, or the size and in shape of the spikelets. Most specimens have ovoidlanceolate spikelets, but some have spikelets which are more obviously ovoid, with loosely arranged glumes and somewhat curved axis, or almost rounded spikelets, not flattened as most Pycreus species, with a low number of glumes which are vere densely compressed. " Pycreus mundtii is easy to recognize as it has leaves up the flowering culm, which separates it from almost all other species in the Flora area. Another good character for this species are the glumes having furrows on each side of the keel, a character which is shared with P. sanguinolentus Vahl. These two species can be easily separated based on habit. In the past, an number of varieties and separate species were described, based on some of these characters. In the FTEA region quite a large number of the specimens can be divided in three groups, according to previous varieties or species. However, quite a distinct number of specimens show characters shared by more than one group, or coincide with each other, and therefore are impossible to identify further than species level; I do believe that varieties can be recognized in this species to a certain level; this distinction will not work on all specimens.

Cyperaceae, Miss S. S. Hooper. Flora of West Tropical Africa 3:2. 1972

Morphology General Habit

A semi-aquatic plant with a generally submerged creeping rhizome

Morphology Leaves

Stiff leaves

Morphology Reproductive morphology Inflorescences

Pale to dark brown clusters of spikelets

Ecology

Stream and lake margins in or near open water.