Schoenus crassiculmis T. L. Elliott & Muasya 2019, sp. nov.
Creators: name: Elliott, T. L.
name: Barrett, R. L.
name: Muasya, A. M.
Publisher: name: Zenodo
Year: 2019
Subjects: Biodiversity
Taxonomy
Plantae
Tracheophyta
Liliopsida
Poales
Cyperaceae
Schoenus
Schoenus crassiculmis

description: 7. Schoenus crassiculmis T.L.Elliott & Muasya, sp. nov.
Type: South Africa, Western Cape Province, 3322 (Oudtshoorn): Swatberg Pass, 25 m up S.-facing slope from road near ‘ Swatberg Pass’ sign; 50 m to N.E. of sign (–AD), 8 May 2016, Elliott & Betz TE2016_050 (BOL!, holo., MT!, iso.).
Caespitose, phyllopodic perennial graminoid, often appearing semi-succulent. Culms terete, robust, (110–)225–327(—468) × 0.5–1.4 mm. Leaves basal, reduced in length and width, 1–4, (7–)18–52(—87) × 0.3–0.5(—1.4) mm, can be straight or curled, often proximally channelled but sometimes flat, margin usually serrate above sheath. Sheaths varying in colour from brown to reddish-purple, firm, attenuate at leaf base, longitudinally striate. Ligule firm, 0.2–1.0 mm long. In fl orescence a pseudolateral panicle, 12–29(—46) × 3–8(—14) mm, proximal rachis length (4–) 7–19 mm. Proximal primary in fl orescence bracts firm, not channelled, apex acute, rarely slightly widened at base, (22–)33–47(— 64) mm long, exceeding length of inflorescence 0.5 times or more, with longitudinal veins. Proximal and subproximal primary inflorescence bracts without membranaceous extensions at base. Spikes 2–13(—16), 4.0–10.0(—20.0) mm long, overlapping, often contracted. Spikelets lanceolate, 3.4–4.8(—6.3) × 0.7–1.4 mm, pedicellate, 1–4(—7) spikelets per spike, reddish-brown in colour (Fig. 4M). Proximal spikelet prophyll 1 per spikelet, well-developed, with raised central vein extending to mucro, 0.5–2.3 mm long, prophyll mucro 0.8–2.3(—3.8) mm long. Rachilla 0.4–1.8(—3.5) mm long. Glumes 4–7 per spikelet, proximal glume 0.6–1.9 mm long, subproximal glume 0.6–2.1 mm long, with or without narrow hyaline margin, upper glumes longer than basal ones, apex acute to acuminate. Glume mucros usually relatively short, proximal mucro 0.1–0.7(—2.0) mm long, subproximal mucro 0.1–0.7 mm long. Stamens 3 per floret, anthers 1.6–2.7(—3.8) mm long. Stigmas 3-branched, vestigial stigmas of second bisexual floret not observed. Perianth bristles lacking. Nutlet broad elliptic, trigonous, yellowish in colour, 2.0–2.5 × 0.7–1.5 mm. Nutlet beak, 0.2–0.9 mm long, hispid (Figs. 2 and 4).
Flowering: May–January
Distribution and ecology: The distribution of Schoenus crassiculmis ranges from the Worcester area of the Western Cape Province to the Willowmore area of the Eastern Cape Province of South Africa (Fig. 16). This species is usually found on sandstone-derived soils on mountain slopes over 900 m in elevation; however, it has been collected from localities with shale parent material.
Diagnosis: Schoenus crassiculmis often appears semi-succulent in the field, with basal leaves that are reduced in length. This species also has relatively short proximal and subproximal glumes. Schoenus auritus appears similar in that it also usually appears semi-succulent in the field; however, the leaves of S. crassiculmis never exceed half the length of the culm, whereas those of S. auritus can be longer than half the culm length. In addition, the lower glumes of S. crassiculmis are relatively short (not over half the spikelet length), while S. auritus has longer glumes that mostly exceed half the spikelet length (Fig. 3M). Bristles and vestigial stigmas have not been observed in S. crassiculmis, but these structures have been observed in S. auritus. Furthermore, S. crassiculmis does not have the membranaceous leaf sheaths that are present in S. auritus. Finally, although the proximal and subproximal primary inflorescence bracts of S. crassiculmis can sometimes be slightly expanded laterally, this expansion is not as notable as in S. auritus.
Additional collections examined
South Africa. WESTERN CAPE: 3219 (Wuppertal): ‘ Groenberg 181’, plateau N.E. of Sederkop: TR 0062, (–AA), 11 Dec 1986, Taylor 11,701 (NBG). 3318 (Cape Town): Jonkershoek, Langrivier, (–DD), 4 Feb 1967, Kerfoot K 5748 (NBG). 3319 (Worcester): Visgat, between Skurweberge and Great Winterhoek Mtns., (–AB), Oct 1953, Stokoe s.n. (SAM); Skurfteberg on farm Visgat (c. 1 mile above TR 312), TR 313, (–AB), 6 Nov 1973, Taylor 8690 (NBG); Mosterts Hoek Twins, (–AD), 8 Jan 1944, Esterhuysen 9873 (BOL); W. slopes of Michell Pk., (–AD), 10 Dec 1948, Esterhuysen 14,805 (BOL, K [2 sheets]); Matroosberg Private Nature Reserve, approximately 200 m upslope from stream, (–BC), 26 Nov 2017, Elliott TE 2016_298 (BOL), Elliott TE2016_299 (BOL); Slanghoek Mts., Krom R. Dome, (–CA), 31 Mar 1945, Esterhuysen 11,519 (BOL); Witteberg, Slanghoek Mts., (–CA), 13 Nov 1949, Esterhuysen 16,504 (BOL); Fonteinjesberg, (–CB), 26 Nov 1944, Esterhuysen 10,962 (BOL, NBG); Wemmershoek Pk., (–CC), Dec 1944, Stokoe s.n. (SAM); 31 Dec 1944, Esterhuysen 11,313 (BOL); 2 May 1945, Esterhuysen 11,602 (BOL); Stettynsberg, (–CD), 16 Dec 1944, Esterhuysen 11,106 (BOL); Riviersonderend range, Bobbejaankop, Mt. Jonaskop, (–DC), 9 Nov 1965, Taylor 6572 (K, PRE); Riviersonderend mountains, Jonaskop, roadside to F.M. tower, (–DC), 14 Jan 1979, Boucher 4212 (NBG, PRE); Haalhoek, Spitzkop, (–DD), 2 Jan 1947, Esterhuysen 13,532 (BOL). 3320 (Montagu): Tweedside (W. Karoo), (–AB), Sep 1926, Wiese s.n. (BOL); Anysberg Nature Reserve, highest plateau on eastern end of Aynsberg, (–DA), 10 Aug 1993, Victor 118 (PRE). 3321 (Ladismith): Toverkop, Swartberg, (–AC), Garcia Forest Station, (–CC), 25 May 1950, Esterhuysen 17,235 (BOL); 15 Dec 1956, Esterhuysen 26,716 (BOL, K), Esterhuysen 26,803 (BOL); S. slopes of the Roodeberg, (–DA), 24 May 1950, Esterhuysen 17,178 (BOL, K); Rooiberg State Forest, 3.4 km from Hut along road edge (eastward), (–DA), 3 Jun 1976, Taylor 9226 (NBG, PRE); Rooiberg, eastern track from pass, (–DA), 17 Jul 1993, van Wyk 599 (PRE). 3322 (Oudtshoorn): Swartberg, (–AC), May 1926, Pocock S 126b (NBG); Swartberg Pass, (–AC), 9 Jun 1977, Bond 1083 (NBG, PRE); Swartberg Pass, 25 m up S.-facing slope from road near ‘ Swartberg Pass’ sign, (–AC), 8 May 2016, Elliott & Betz TE 2016_049 (BOL), Elliott & Betz TE 2016_050 (BOL), Elliott & Betz TE 2016_051 (BOL); Swartberg Pass, c. 100 m S. of road, beside a spur trail along ‘ Ou Tol’ hiking trail, (–AC), 8 May 2016, Elliott & Betz TE 2016_054 (BOL), Elliott & Betz TE 2016_056 (BOL), Elliott & Betz TE 2016_063 (BOL); Swartberg Mountains, peak E. of Spitskop, (–AD), 13 Nov 1985, Vlok 1286 (PRE, WAG); Swartberg mountains, top of Blouberg, (–AD), 3 Mar 1987, Vlok 1851 (PRE, WAG); lower S.E. slopes of Kamanassie Mts. at Laudina, (–DB), 9 Nov 1949, Esterhuysen 16,465 (BOL, NBG). EASTERN CAPE: 3323 (Willowmore): Hoopsberg, (–CB), 6 Nov 1941, Esterhuysen 6565 (BOL); Formosa Pk., near Lanternwater Summit, (–DC), 1 Dec 1957, Esterhuysen 27,392 (BOL, K); Kouga Pk. near Joubertina, (–DD), 27 Oct 1949, Esterhuysen 16,262 (BOL, NBG).
description: Published as part of Elliott, T. L., Barrett, R. L. & Muasya, A. M., 2019, A taxonomic revision of Schoenus cuspidatus and allies (Cyperaceae, tribe Schoeneae) - Part 1 *, pp. 519-535 in South African Journal of Botany 121 on pages 530-531, DOI: 10.1016/j.sajb.2018.11.021, http://zenodo.org/record/10496596