A taxonomic revision of Schoenus cuspidatus and allies (Cyperaceae, tribe Schoeneae) - Part 1 *
Author
Elliott, T. L.
Author
Barrett, R. L.
Author
Muasya, A. M.
text
South African Journal of Botany
2019
2019-03-31
121
519
535
http://dx.doi.org/10.1016/j.sajb.2018.11.021
journal article
10.1016/j.sajb.2018.11.021
1727-9321
10496596
4. Key to the species in the
Schoenus cuspidatus
group (part I)
1a. Proximal primary inflorescence bract conspicuously expanded at base; longitudinal veins at base of bract often prominent: 2a. Culms usually thick (
0.7–1.1 mm
wide) and appearing semi-succulent; plants widespread throughout
South Africa
(usually found within
200 km
of the S. and E. coasts): ……………………………………………………………
1
.
Schoenus auritus
2b. Culms thin (
0.4–0.6 mm
) and not appearing semi-succulent; plants restricted to granitic sites on the
Cape
Peninsula: ……………………………………………………
2
.
Schoenus graminifolius
1b. Proximal primary inflorescence bract not conspicuously expanded at base; longitudinal veins at base of bract not prominent: 3a. Spikelets linear-lanceolate (
Fig. 1
); nutlets narrow-ellipsoidal (
Fig. 2C, D
): 4a. Plants usually>
350 mm
in height; spikelets
4.5–7.5 mm
in length, often reduced sexually with only male or female organs present:………………………………………………
3
.
Schoenus ligulatus
4b. Plants <
340 mm
in height; spikelets mostly <
4 mm
in length, bisexual spikelets always present:………………………
4
.
Schoenus exilis
3b. Spikelets lanceolate or ovate (
Fig. 1
); nutlets broad-ellipsoidal (
Fig. 2
): 5a. Spikelets lanceolate:
Fig. 1.
Spikelet variation in the
Schoenus cuspidatus
and allies group found in southern Africa: A—
S. cuspidatus
(lanceolate spikelet), B—
S. crassus
(lanceolate spikelet), C—
S. auritus
(lanceolate spikelet), D—
S. graminifolius
(lanceolate spikelet), E—
S. calceolus
(ovate spikelet) and F—
S. ligulatus
(linear-lanceolate spikelet). The black scale bar next to the spikelets represents 1 mm.
6a. Glume margins with reddish-purple streaks adjacent to the hyaline margins (
Fig. 3E, F
): 7a: Older leaves usually curled; membranaceous sheaths with reddish-purple streaks:………………………………
5.
Schoenus bolusii
7b. Older leaves usually straight; sheaths firm (i.e. not membranaceous) and solid red to brown in colour: ……………………………………………..……
6.
Schoenus submarginalis
6b. Glume margins without reddish-purple streaks adjacent to the hyaline margins: 8a. Basal leaves reduced in length (usually a third to a quarter of culm length, never over half of culm length); glumes usually dark-reddish brown in colour; plants of mountainous regions of the Western and
Eastern Cape
Provinces:……….…….…….......………
7.
Schoenus crassiculmis
8b. Basal leaves well-developed in length (often over half of culm length); glumes medium brown to light reddish-brown in colour; plants endemic to the
Eastern Cape
and
KwaZulu-Natal
or
Agulhas Plains region
of
South Africa
): 9a. Spikelets <4.0 mm in length; glumes often thin and membranaceous (
Fig. 4N
); plants endemic to quartz patches on shale-derived soils in the Overberg region of the
Western Cape Province
of
South Africa
:…..…...……………………....…....
8.
Schoenus quartziticus
9b. Spikelets usually>4.0 mm in length; glumes firm (
Fig. 4O
); plants endemic to grasslands and wetlands of the
Eastern Cape
and
KwaZulu-Natal
Provinces of
South Africa
):……...….
9.
Schoenus limosus
5b. Spikelets ovate (
Fig. 1
): 10a. Sheaths loose; leaves appearing flat as they are usually not-channelled above ligule; plants endemic to mountainous regions of the southern
Western Cape Province
of
South Africa
: ……………………………………...….………...
10.
Schoenus purpurascens
10b. Sheaths firm; leaves appearing terete as they are channelled above ligule; plants endemic to the Agulhas Plains region of
South Africa
: 11a. Spikelets with firm prophylls that often shine; prophyll mucros>3.0 mm; base of culms terete and with sheath not holding several leaf bases together:………………………………….….
11.
Schoenus prophyllus
11b. Spikelets with prophylls that are not firm and shining; prophyll mucros <
2.4 mm
long; base of culm flattened and with sheath holding several leaf bases together (
Fig. 5
):………………..
12
.
Schoenus calceolus