Schoenus crassus (Levyns) T.L.Elliott & Muasya, S.

Elliott, T. L. & Muasya, A. M., 2020, A taxonomic revision of Schoenus cuspidatus and allies (Cyperaceae, tribe Schoeneae) - Part 2, South African Journal of Botany 130, pp. 327-347 : 335-336

3. Schoenus crassus (Levyns) T.L.Elliott & Muasya, S. African J. Bot. 112: 359 (2017).

Tetraria crassa Levyns, J. S. African Bot. 13: 87 (1947).

Type: South Africa, Western Cape Province, 3418 (Simonstown): Smitswinkel Bay , (‒AD), 22 May 1938, Levyns 6580 (BOL, lecto.! [ BOL139421 — “ Sheet I ”], here designated; BOL! [ BOL139422 , BOL139423 ], iso.). [Note: The three specimens of Levyns 6580 stored at BOL lacked any indications of which should be the holotype; therefore, a lectotype was chosen by T.L. Elliott.].

Elynanthus microstachyus Boeckeler, Linnaea 38: 261 — 262 (1874), pro parte. Schoenus microstachyus (Boeckeler) Kuntze, Revis. Revis. Gen. Pl. 2: 756 (1891). Type: South Africa, Western Cape Province, 3319 (Worcester): Dutoits Kloof, (— CA), without date, Drege s.n. (K, lecto. [K000244909] — image!, here designated; K!, iso.). [Note: As noted by Clarke ( Durand and Schinz, 1894, p. 661), E. microstachyus is also a synonym of Tetraria fasciata (Rottb.) C.B. Clarke , since Boeckeler (1874a) cited specimens corresponding to both species. Clarke’ s handwriting on K000244909 notes that Boeckeler (1874a) incorrectly cites this specimen (i.e. Drege a.a.) in the protologue of E. microstachyus .].

[Note: The specimen from K (i.e. the one currently without a barcode) has ‘ microstachyus ’ written on it in pencil. This specimen is also numbered Drege 1040.].

[Note: As Kuntze (1891) does not explicitly state which specimen the new combination Schoenus microstachyus refers to, we have also included it as a synonym of S. cuspidatus .].

[Note: Elliott and Muasya (2017) previously listed Elynanthus microstachyus as a synonym of S. cuspidatus . However, this name now fits under the revised circumscription of S. crassus .].

[ Tetraria cuspidata (Rottb.) C.B.Clarke var. b aristata C.B.Clarke ms (var.? b aristata written on Drege 1040 (K) by C.B. Clarke).]

Caespitose, robust, phyllopodic perennial graminoid ( Fig. 3C ). Culms terete, relatively wide, (455 —)509 — 579(— 821) X 0.6 — 1.4(— 1.7) mm. Leaves basal, less than half culm height or more, 1 — 6, (144 —)166 — 234 (— 420) X 0.5‒1.1(— 1.5) mm, proximally channelled, margin usually serrate above sheath, firm and stiff, rigid acuminate tips, often straight but sometimes curled. Sheaths reddish-brown at base but paler above, firm (often tinged orange), longitudinally striate. Ligule firm, lobes obtuse, 0.3 — 1.4 mm long. In fl orescence a pseudolateral panicle, appearing ‘bearded’, light reddish-brown when young (tinged orange) maturing grey-brown, 36‒47(— 50) X (3.5 —)6.8‒9.0 (— 11.0) mm, proximal rachis length 10.5‒21.0(— 24.0) mm ( Fig. 3H ). Proximal primary in fl orescence bracts firm, often slightly thickened, apex acuminate, channelled, narrow at base, (64 —)74‒92(— 113) mm long, exceeding length of inflorescence up to several times. Spikes varying in number 4‒24, 5‒12 (— 15) mm long, slightly overlapping. Spikelets lanceolate, 4.2‒5.2 (— 5.9) X (0.6 —)0.9‒1.1(— 1.5) mm, pedicellate, 2 — 4 spikelets per spike, light reddish-brown in colour ( Fig. 5C ). Proximal spikelet prophyll 1 per spikelet, firm, well-developed and thickened, light reddish-brown when young, sometimes obscures part of spikelet, with notable, raised vein extending to mucro, 0.8‒1.6(— 2.2) mm long, mucros often long, (1.0 —)2.6‒3.9(— 8.0) mm long. Rachilla 0.5‒2.2(— 3.2) mm long. Glumes 4‒7 (usually 5‒6) per spikelet, often firm, hyaline margins, first three glumes usually relatively long and aristate, proximal glume 1.1‒2.0 (— 2.7) mm long, subproximal glume 1.2‒2.1(— 2.7) mm long, upper glumes longer than basal ones and with hyaline margines, apex acuminate to acute. Glume mucros varying in length, proximal mucro (0.8‒) 1.4‒1.8(— 1.9) mm long, subproximal mucro 0.6‒1.2(— 1.4) mm long. Stamens 2‒3 per floret, anthers (0.9‒)2.2‒2.9(— 3.5) mm long. Stigmas 3-branched, vestigial stigmas of second bisexual floret absent (i.e. yet to be observed). Perianth bristles absent (i.e. yet to be observed). Nutlet usually broad elliptic, sometimes relatively long, trigonous, yellowish in colour when young, maturing reddish and sometimes with grey spots ( Fig. 6C ), no measurements made as nutlets were not in a measurable state. Nutlet beak hispid.

Flowering: January to June (usually April to June)

Distribution and ecology: Schoenus crassus is endemic to the Western Cape Province of South Africa, with a distributional range extending from the Cape Peninsula in the west to the Langeberg Mountain Range in the east ( Fig. 9 ). This species has a wide elevation range, as specimens have been collected from as low as 45 m to nearly 1550 m in the mountains. It is a species that generally prefers coarse-textured sandstone-derived soils in the fynbos vegetation type; however, it has also been collected from sites with granite and limestone parent material. In addition, S. crassus is reported to occur on wet sites, such as seepage areas and damp depressions.

Diagnosis: Schoenus crassus is a robust plant, usually with stiff upright leaves ( Fig. 3C ). This species often has firm and thickened primary inflorescence bracts, prophylls and prophyll mucros, as well as aristate spikelets ( Figs. 3H and 5C ). Many of these characters are also exhibited in S. compactus ( Figs. 3G and 5B ); however, the main character separating the two species is the inflorescence shape, whereas that of S. crassus is elongate with the rachis notably lengthened among spikes, the inflorescence of S. compactus is short and congested.

Schoenus crassus is often confused with S. cuspidatus based on general growth habit and inflorescence characters; however, there are a few key vegetative and reproductive differences between the two species. First, S. crassus has aristate spikelets with relatively long lower glumes compared to those of S. cuspidatus , whose spikelets are cuspidate with relatively short lower glumes ( Fig. 5C and F ). In addition, the primary inflorescence bracts, prophylls and prophyll mucros of S. cuspidatus are not as thickened and firm as those of S. crassus ( Figs. 3H and 4E ). The overall habit of S. crassus appears more stiff and rigid compared to S. cuspidatus ( Figs. 3C and 4A ), which is a more lax-looking plant often having curled leaves ( S. crassus usually has stiff, straight leaves).

This species displays considerable geographical intraspecific variation. In general, plants from the Cape Peninsula and adjacent regions are larger and more robust compared to plants from more eastern and northern sites. In addition, the primary inflorescence bracts and prophyll mucros of plants collected from Worcester and adjacent areas (e.g. Stellenbosch) appear to break-off the inflorescences more readily.

Additional collections examined

South Africa. WESTERN CAPE: 3318 (Cape Town): Steenbras area, (— BB), 1 May 1948, Levyns 8871 (BM, BOL); near Steenbras Siding, (— BB), 11 Sep 1949, Levyns 9431 (BOL); Riverlands Nature Reserve, S. W. of Malmesbury, (— BC), 23 Nov 2002, Verboom 631 (BOL); Dutoitsberge, lower W. slopes, farm Fisantekraal, (— CA), 29 Feb 2004, Verboom 703 (BOL); above Pipe Track, (— CD), Apr 1926, Wiese s.n. (BOL); Malmesbury district, Morewag farm, W. of Paardeberg, (— DA), 5 Sep 1979, Boucher 4579 (K, NBG, PRE); Jonkershoek Twins, E. slopes, (— DD), 14 Feb 1945, Esterhuysen 11,460 (BOL); E. slopes of Buller’ s Kop, Gt. Drakenstein Mts, (— DD), 30 Sep 1945, Levyns 11,903 (BOL); Swartboschkloof, Jonkershoek, (— DD), 23 Feb 1960, Van der Merwe 20,100 (NBG); Jonkershoek, (— DD), 19 Apr 1962, Taylor 3276 (NBG), Taylor 3268 (NBG); Oct 1967, Kerfoot s.n. (NBG); Tally 3 — 570, Belt 13E, Jakkalsvlei, Jonkershoek, (— DD), 19 Apr 1962, Taylor 3268 (PRE); near Talley 3 — 740, Belt 13E, Jakkalsvlei, Jonkershoek, (— DD), 19 Apr 1962, Taylor 3276 (PRE); Jonkershoek List 4, (— DD), 20 Sep 1965, Taylor 6503 (NBG); Jakkalsvlei, Jonkershoek, (— DD), 20 Sep 1965, Taylor 6503 (NU [2 sheets], PRE [2 sheets]); Jonkershoek Nature Reserve, ca. 20‒30 m S.W. of junction of Panorama and Swartboskloof trails, towards Guardian Peak from junction, (— DD), 22 Sep 2016, Elliott & Muasya TE2016_103 (BOL). 3319 (Worcester): Witteberg, vlakte between Kromrivier Peak and Witteberg Peak, (— BD), 12 Feb 2004, Verboom 698 (BOL); Bains Kloof, summit of Limietberg, (— CA), 5 Jan 1949, Adamson 8143 (BOL); Limietberg Nature Reserve, Happy Valley trail, (— CA), 27 Apr 2017, Elliott, Muasya & Betz TE2016_186 (BOL); Dutoits Kloof, (— CA), without date, Drege 1040 (K); Paardekop,Wemmershoek Mts., (— CC), 2 May 1945, Esterhuysen 11,581 (BOL), Esterhuysen 11,582 (BOL, K); French Hoek Pass about 1 km S. of the summit above road, (— CC), 9 Oct 1973, Boucher 2319 (K, NBG); Bosjesveld mountains, Villiersdorp side, (— DC), Feb 1940, Stokoe s.n. (SAM). 3320 (Montagu): Langeberg, Swellendam State Forest, N-facing rocky ridge leading to Hermitage Peak, site overlooks Langkuile, (— CD), 19 Oct 1988, McDonald 1652 (NBG, PRE); Langeberg, Swellendam State Forest, S. side of ridge that extends up to Hermitage Peak, (— CD), 19 Oct 1988, McDonald 1655 (NBG); Marloth Nature Reserve, ca. 100‒125 m to N. of Goedgeloof Hut, (— CD), 17 Sep 2018, Elliott & van Mazijk TE2016_401 (BOL). 3418 (Simonstown): Silvermine Nature Reserve, N. facing slope below Steenberg Peak, (— AB), 9 Jun 2002, Verboom 538 (BOL); CPNR, Judas peak, (— AB), 10 Mar 2017, Euston-Brown 5210 (BOL), Euston-Brown 5211 (BOL); Smitswinkel vlakte, (— AD), 17 Jun 1966, Taylor 6859 (NBG); Cape of Good Hope Nature Reserve, between main road and Anvil Rock, (— AD), 23 Oct 2005, Verboom 900 (BOL), Verboom 901 (BOL); Steenbras Dam Forest Reserve, (— BB), 10 May 1982, Getliffe 1099 (NU); Palmiet River Mouth, (— BD), 6 May 1948, Levyns 8890 (BOL); slopes of Kogelberg, (— BD), 1 Sep 1953, Stokoe s.n. (SAM); Kogelberg Forest Reserve, (— BD), 6 Aug 1969, Boucher B37 (NBG); N. side of Blesberg facing disused goal. plot 300/28, 12 Jan 1970, Boucher 1062 (NBG); Kogelberg Research Site next to plot 5, (— BD), 30 Apr 1980, Le Maitre 86 (NBG); Kogelberg State Forest, Research Site, (— BD), 20 May 1980, Le Maitre 105 (NBG, PRE); 12 May 1980, Le Maitre 206 (K, NBG); Kogelberg Nature Reserve, along Palmiet River Walk, (— BD), 18 Nov 2016, Elliott & Muasya TE2016_146 (BOL); on mountain slope N. of 'Harold Porter National Botanical Garden', along 'Zigzag Trail Path', (— BD), 29 Nov 2017, Elliott & Smith TE2016_312 (BOL). 3419 (Caledon): Nuweberg Forest Reserve, source of Palmiet River, (— AA), 21 May 1969, Stehle TS 133 (NBG); Houwhoek, Houwtech, (— AA), 26 Jan 1988, Boucher & Stindt 5361 (NBG); Houwhoek, Houwtech terrain, E. of Lookout, (— AA), 6 Apr 1988, Boucher & Stindt 5376 (NBG); Hottentots Hollands Nature Reserve, ca. 3 km from Nuweberg parking lot, along jeep track to Landdroskop Hut, (— AA), 18 Feb 2017, Elliott & Muasya TE2016_175 (BOL); Houw Hoek, (— AA), 2 Jul 1896, Schlechter 7404 (BM, K, PRE, SAM, WAG); Lebanon, Catchment IId, (— AB), Apr 1967, Kruger KR 438 (PRE); Grabouw, Highlands Forest Reserve, Perdeberg, (— AC), 3 Mar 2002, Verboom 507 (BOL); Kogelberg Nature Reserve, near Highlands parking area, (— AC), 17 Nov 2002, Verboom 609 (BOL); Fernkloof Nature Reserve, along Klipspringer Path, (— AC), 10 Feb 2017, Elliott TE2016_164 (BOL); Fernkloof Nature Reserve, Hermanus, (— AD), 5 Mar 1974, Orchard 61 (K, NBG), Orchard 66 (NBG); Vogelgat, near Base Camp, (— AD), 20 Apr 1978, Williams 2473 (NBG); Vogelgat Nature Reserve, part way between Window and Die Mond view, (— AD), 25 Apr 2016, Elliott & Betz TE2016_007 (BOL), Elliott & Betz TE2016_008 (BOL), Elliott & Betz TE2016_009 (BOL), Elliott & Betz TE2016_010 (BOL), Elliott & Betz TE2016_011 (BOL), Elliott & Betz TE2016_012 (BOL); Nidderdale Farm, S.E. facing slope to N.E. of Babylon's Tower peak, (— AD), 5 May 2018, Elliott, Muasya & van Mazijk TE2016_354 (BOL); Vogelgat Private Nature Reserve, growing on edge of ‘Lone Tree Stream’, (— AD), 24 Aug 2018, Elliott TE2016_366 (BOL); Genadendal, (— BA), 21 Dec 1896, Schlechter 9802 (BM, BR, GRA, K, PRE, WAG); 1 Apr 1897, Schlechter 10,295 (BM, BOL, BR, K, WAG); Zwarteberg, Sandfontein, (— BA), 6 Apr 1897, Schlechter 10,343, (BM, BOL, BR, GRA, K, WAG); Riviersonderendberge, (— BB), 7 Apr 1974, Theron & stud. 3004 (PRE); Kleinmond, (— BD), 22 May 1948, De Vos 1019 (NBG); near Cape Hangklip, (— BD), 2 May 1949, Levyns 9397 (BM); between Rooi Els Cape Hangklip, (— BD), 2 May 1949, Levyns 9397 (BOL); sandy flats near Pringle Bay, 3 Jun 1953, Parker 4871 (BOL). 3420 (Bredasdorp): De Hoop, Potberg Nature Reserve, limestone hills above De Hoop pass, (— AD), 13 Jun 1979, Burgers 1850 (NBG); De Hoop Nature Reserve, Potberg Mountain, ca. 2 — 4 km along 'Whale Trail' from start of hike, (— BC), 30 Nov 2017, Elliott & Smith TE2016_321 (BOL); De Hoop Nature Reserve, Potberg Mountain, ca. 750‒1000 m along 'Whale Trail' from start of hike, (— BC), 30 Nov 2017, Elliott & Smith TE2016_330 (BOL). 3421 (Riversdale): Langeberge Summit above Riversdale, (— AB), 19 May 1950, Esterhuysen 17,020 (BOL).

Figures

Fig. 3. Examples of plants from five species of the S. cuspidatus and allies group found in Southern Africa, showing the corresponding inflorescences beneath each plant: A and F—S. brunnescens; B and G—S.compactus; C and H—S.crassus; D and I—S.loreus; and E and J—S.galpinii. The black scale bar adjacent to the inflorescence in J represents 10 mm.

Fig. 5. Examples of spikelets from nine species of the S. cuspidatus and allies group found in Southern Africa:A—S. brunnescens; B—S. compactus; C—S. crassus; D—S.loreus; E—S. gal- pinii; F—S.cuspidatus; G—S.graciliculmis; H—S.riparius; and I—S.australis. The black scale bar represents 1 mm.

Fig. 6. Examples of nutlets from nine species of the S.cuspidatus and allies group found in Southern Africa:A—S. brunnescens; B—S. compactus; C—S. crassus; D—S. loreus; E—S. galpinii; F—S.cuspidatus; G—S.graciliculmis; H—S.riparius; and I—S.australis. The black scale bar represents 1 mm.

Fig. 9. Documented locations of S.crassus.

Fig. 4. Examples of plants from four species of the S.cuspidatus and allies group found in Southern Africa, showing the corresponding inflorescences beneath each plant: A and E—S. cuspidatus; B and F—S.graciliculmis; C and G—S.riparius; and D and H—S.australis. The black scale bar adjacent to the inflorescence in H represents 10 mm.