Schoenus crinitus T.L.Elliott & Muasya, 2020

Elliott, T. L. & Muasya, A. M., 2020, A taxonomic revision of the Epischoenus group of Schoenus (Cyperaceae, tribe Schoeneae), South African Journal of Botany 135, pp. 296-316 : 309

6. Schoenus crinitus T.L.Elliott & Muasya , sp. nov.

Type: South Africa, Western Cape Province, 3319 (Worcester): Limietberg Nature Reserve , growing on SE-facing slope of R301, c. 4 km to NE of Bainskloof community, (‒CA), 18 Nov 2019, Elliott & Arens TE2016_446A ( BOL!, holo.; MT!, iso.) .

Caespitose, perennial graminoid, aphyllopodic, hairy ( Fig. 4A and 4G ). Culms hairy and ridged (evident on dried specimens), (730 —) 834 — 894(‒965) £ 0.6 — 0.8 mm. Leaves absent. Sheaths dark reddish-black, longitudinally striate, open, central vein terminating in a mucro up to several mm long, semi-firm to firm. Ligule absent. In fl orescence a depauperate, pseudolateral panicle, (32 —)49‒60(‒ 69) £ 2.0‒6.0(‒10.0) mm, proximal rachis length 11.0‒37.3(‒45.0) mm ( Fig. 4G and 7F ). Proximal primary in fl orescence bracts (61 —)72‒ 84(‒96) mm long, rigid, without lateral chartaceous extensions, involute, narrow at base, apex acute, exceeding length of inflorescence slightly. Spikes 2, (7 —)18‒29(‒34) mm long, aggregated into small clusters along rachis, sometimes slightly overlapping. Spikelets lanceolate, hairy, 1 — 3 spikelets per spike, (6.3 —)7.1‒7.9(‒8.3) £ (0.9 —)1.2‒ 1.7(‒2.1) mm, pedicellate, colour reddish-brown, texture firm and opaque, not concealed by primary inflorescence bracts, varying number of sterile glumes at spikelet base ( Fig. 8F ). Proximal spikelet prophyll sometimes present, 1.7 mm (one measured), mucros 1.7‒ 1.8 mm long when present. Rachilla varying greatly in length, (1.1‒) 2.9‒13.7(‒20.6) mm long. Glumes 4‒8 per spikelet, texture opaque and firm, hairy, without hyaline margins, proximal glume varying in length, (1.4‒)2.5‒3.3(‒4.0) mm long, subproximal glume (1.7‒)3.1‒ 3.7(‒4.6) mm long, upper glumes longer than basal ones, apex acute to obtuse. Glume mucros often absent, proximal mucro 0‒0.1(‒0.6) mm long, subproximal mucro 0‒0.2(‒2.1) mm long. Stamens 2 — 3 (usually 3) per floret, anthers 2.9 mm long (1 measured). Stigmas 3- branched, vestigial stigmas present. Perianth bristles absent (i.e. yet to be observed). Suprafloral axis sometimes thickening and strengthening, eventually curving. Nutlet (no fully mature nutlets observed), 2.9 £ 1.5 mm (one measured), broad elliptic, trigonous, matt, yellowish in colour, sessile; nutlet beak absent from immature nutlets that were examined ( Fig. 10F ). ( Figs. 3 , 7 , 8 and 10 )

Flowering: Two specimens were collected while flowering: one in June and the other in February

Distribution and ecology: Schoenus crinitus is only known from the area surrounding Bainskloof Pass in the Western Cape Province of South Africa ( Fig. 16 ). The specimens with habitat information were collected from wet, mountainous sites.

Diagnosis: Schoenus crinitus is a rigid, hairy species having inflorescences with few, dispersed spikelets. Schoenus neovillosus and S. lucidus also have hairy spikelets and/or culms (especially when young); however, the spikes of those two species are appressed between the primary inflorescence bracts, whereas the primary inflorescence bracts of S. crinitus are relatively narrow and the inflorescences have more lateral branching. Furthermore, the culms of S. crinitus have deeper ridges compared to the almost round shallowridged culms of S. neovillosus and S. lucidus .

Schoenus adnatus , S. gracillimus and S. schonlandii have a similar overall inflorescence form to S. crinitus , with narrow primary inflorescence bracts that are dispersed along the central rachis. The main differences in these four species is the general hairiness of S. crinitus compared to the other three species: hairs have yet to be observed in S. schonlandii , whereas only occasional hairs have been observed on the spikelets and/or culms of S. adnatus and S. gracillimus . In contrast to the relatively thin and ‘lax’ culms of S. adnatus and S. gracillimus , the culms of S. crinitus are usually more rigid.

Additional collections examined

South Africa. WESTERN CAPE: 3319 (Worcester): top of Bain's Kloof , (‒CA), Feb 1928, Stokoe 1618 ( BOL) ; Bain's Kloof Pass, slopes above road between Eerste Tol and Tweede Tol , (‒CA), 1 Oct 2006, Verboom 1144 ( BOL) ; Bainskloof Pass, (‒CA), 12 Sep 2015, Muasya 7263 ( BOL) ; Limietberg Nature Reserve , growing on SE-facing slope of R301, c. 4 km to NE of Bainskloof community, (‒CA), 25 Jun 2017, Elliott & Muasya TE 2016_207 ( BOL) , Elliott & Muasya TE 2016_208 ( BOL) .

Figures

Fig. 4. Examples of plants from six species of the Epischoenus group found in southern Africa, showing the corresponding inflorescences beneath each plant: A and G—S.crinitus; B and H—S. adnatus; C and I—S. gracillimus; D and J—S. schonlandii; E and K—S. lucidus; and F and L—S. neovillosus. The black scale bar adjacent to the inflorescence in L represents 10 mm.

Fig. 7. Diagrammatic representations of the inflorescences of 11 species in the Epischoenus group, with spikelets illustrated in dark grey, primary inflorescence bracts in white and chartaceous (membranaceous) lateral extensions of the primary inflorescence bracts in light grey. Illustrations are not drawn to exact scale and stippling represents hairs. Inflorescences of the following species are shown: A—S. dregeanus; B—S. complanatus; C—S. quadrangularis; D—S. selinae; E—S. rigidus; F—S. crinitus; G—S. adnatus; H—S. gracillimus; I—S. schonlandii; J—S. lucidus; and K—S.neovillosus.

Fig. 8. Examples of spikelets from 11 species of the Epischoenus group found in southern Africa: A—S.dregeanus; B—S.complanatus; C—S. quadrangularis; D—S. selinae; E—S.rigidus; F—S.crinitus; G—S.adnatus; H—S.gracillimus; I—S.schonlandii; J—S.lucidus; and K—S.neovillosus. The black scale bar beside K represents 1 mm.

Fig. 10. Examples of nutlets from 11 species of the Epischoenus group found in southern Africa: A—S. dregeanus; B—S.complanatus; C—S. quadrangularis; D—S. selinae; E—S.rigidus; F—S.crinitus; G—S.adnatus; H—S.gracillimus; I—S.schonlandii; J—S.lucidus; and K—S.neovillosus. The black scale bar beside K represents 1 mm. Fully formed, mature nutlets of S.crinitus and S. neovillosus have yet to be observed.

Fig. 3. Examples of plants from five species of the Epischoenus group found in southern Africa, showing the corresponding inflorescences beneath each plant: A and F—S. dregeanus; B and G—S.complanatus; C and H—S. quadrangularis; D and I—S.selinae; and E and J—S.rigidus. The black scale bar adjacent to the inflorescence in L represents 10 mm.

Fig. 16. Documented locations of S.crinitus.