Cyperus longispicula Muasya & D.A.Simpson

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: threatened. Confidence: confident

Simpson, D., & Muasya, A. (2004). Three New Species of Cyperus (Cyperaceae) from Eastern and Southern Africa. Kew Bulletin, 59(4), 593-598. doi:10.2307/4110917

Type

Zimbabwe,J. M. Rattray 1273 (holotypus K!, isotypus SRGH).

Morphology General Habit

Shortly rhizomatous perennial

Morphology Culms

Culms moderately to densely tufted, 18 - 32 cm x 0.7 - 0.9 mm, terete to ± trigonous, smooth, green, densely covered at base by mid- to dark brown leaf sheath remains

Morphology Leaves

Leaf blade narrowly linear, 6 - 29 cm x 0.4 - 0.7 mm, very gradually tapering to an acute apex, flat in cross- section, margins smooth, green; sheath 2.5 - 3.5 cm long, mid-brown

Morphology Reproductive morphology Inflorescences Bracts

Involucral bracts 2 - 3, leaf-like, the longest 6 - 12 cm long, margins smooth

Morphology Reproductive morphology Inflorescences

Inflorescence lax capitate, 2.5 - 5 x 4 - 5.5 cm

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets 14 - 18 per inflorescence, linear, (1 -) 1.8 - 2.5 cm x 1.8 - 2.4 mm, flattened, reddish-brown, rachilla straight

Morphology Reproductive morphology Inflorescences Bracts Glume

Glumes 18 - 44 per spikelet, ovate-lanceolate, 2.4 - 2.7 x 1 - 1.6 mm, ± acute, sides membranous, 2 - 3- nerved on each side, mid-reddish brown, keel green to pale brown

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens 3; anthers 1.2 mm long

Morphology Reproductive morphology Flowers Gynoecium Stigma

Stigmas 3

Morphology Reproductive morphology Fruits

Nutlets obovate, trigonous with convex sides, 0.7 - 0.8 x 0.4 mm, maturing dark brown, very minutely papillose.

Distribution

Mozambique, Zimbabwe

Ecology

Peaty soil in rock fissures, shallow soil on rock outcrops, vlei grassland on quartzite sands; 430 - 500 m.

Note

Name refers to the distinctly long spikelets possessed by this species. Cyperus longispicula is related to C. kirkii, differing by its larger inflorescence and longer spikelets. Its relationship to C. kirkii places it within sect Amabiles C. B. Clarke, a natural grouping of taxa characterised by narrow spikelets and small reddish to brown glumes. This was accepted by Kiukenthal (1936). Interestingly Haines & Lye (1983) include this section and sect. Platystachyi together in subgen. Xerocyperus Lye, despite the taxa being morphologically distinct. They do, however, say that subgen. Xerocyperus is heterogeneous and could be split into 3 - 4 subgenera. We favour the sectional classification adopted by Kiukenthal, as we feel that subgeneric recognition places too much importance on what are relatively small groups of taxa.

Conservation

We assess this plant as Data Deficient (DD) using the IUCN criteria (IUCN 2001). We have no information about the status of the habitats in which the plants occur.

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

Zimbabwe, Lower Sabi, 27.i-2.ii.1948, Rattray 1273 (K holotype, SRGH).

Morphology General Habit

Shortly rhizomatous perennial-Culms moderately to densely tufted, 18–32 cm by 0.7–0.9 mm, terete to trigonous, smooth, green, densely covered at base by mid- to dark brown leaf sheath remains

Morphology Leaves

Leaves: blade narrowly linear, 6–29 cm by 0.4–0.7 mm, very gradually tapering to an acute apex, flat in cross-section, margins smooth, green; sheath 2.5–3.5 cm long, mid-brown

Morphology Reproductive morphology Inflorescences Bracts

Involucral bracts 2–3, leaf-like, the longest 6–12 cm long, margins smooth

Morphology Reproductive morphology Inflorescences

Inflorescence lax capitate, 2.5–5 × 4–5.5 cm

Morphology Reproductive morphology Inflorescences Spikelets

Spikelets 14–18 per inflorescence, linear, (1)1.8–2.5 cm by 1.8–2.4 mm, flattened, reddish brown, rachilla straight

Morphology Reproductive morphology Inflorescences Bracts Glume

Glumes 18–44 per spikelet, ovate-lanceolate, 2.4–2.7 × 1–1.6 mm, ± acute, sides membranous, 2–3-nerved on each side, mid-reddish brown, keel green to pale brown

Morphology Reproductive morphology Flowers Androecium Stamens

Stamens 3; anthers 1.2 mm long

Morphology Reproductive morphology Flowers Gynoecium Stigma

Stigmas three

Morphology Reproductive morphology Fruits

Nutlets obovate, trigonous with convex sides, 0.7–0.8 × 0.4 mm, maturing dark brown, very minutely papillose.

Distribution

Zimbabwe, Mozambique. Not known elsewhere;

Ecology

Peaty soil in rock fissures; shallow soil over granite and Permian rocks; dambo grassland on sand; 400–500 m.

Conservation

Known from only four collections, all in much the same area straddling the Mozambique–Zimbabwe border. Data Deficient as few specimens and restricted distribution.