Schoenus dregeanus

Last updated

Schoenus dregeanus
S dregeanus habit-1.jpg
Slim veldrush
Scientific classification OOjs UI icon edit-ltr.svg
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Clade: Commelinids
Order: Poales
Family: Cyperaceae
Genus: Schoenus
Species:
S. dregeanus
Binomial name
Schoenus dregeanus
(Boeckeler) Kuntze
S dregeanus-map.pdf
Documented collection localities in South Africa
Synonyms [1]
  • Elynanthus dregeanus Boeckeler
  • Tetraria dregeana (Boeckeler) C.B.Clarke
  • Epischoenus dregeanus (Boeckeler) Levyns

Schoenus dregeanus is a species of sedge endemic to mountainous locations in south-western South Africa. [1]

Contents

Description

Schoenus dregeanus is a species of southern African Schoenus displaying characters of the Epischoenus, Schoenus cuspidatus and allies, as well as the Schoenus compar - Schoenus pictus and allies groups. [1] The presence of leaves (often over 30 mm long) along the lower parts of the flowering stems (culms) differentiates this species from others in the Epischoenus group; however, the last internode of the spikelets are elongated, similar to other species in that group. [1] In addition to intermediate morphological characteristics, evolutionary studies often show that S. dregeanus is placed outside of the Epischoenus group of Schoenus and not embedded within the clade. [1]

The nutlets (fruits) of S. dregeanus are rough at the base and apex, which differs from the entirely matted or shiny nutlets characteristic of other species in the Epischoenus group, such as those of Schoenus gracillimus and Schoenus lucidus . [1]

Similar to Schoenus ligulatus , S. dregeanus has linear spikelets. [2] [1] However, the spikelets of S. ligulatus have prophylls (bracts) at their base, whereas those of S. dregeanus lack this structure. [1] [2]

Although S. dregeanus and S. gracillimus sometimes morphologically resemble each other and their distributions overlap, the spikelets of S. gracillimus are often pendulous in this region. [1]

The tendency of species in the southern African Schoenus to form hybrids with each other partially explains why they can be difficult to identify. [3] Preliminary evidence suggests that S. dregeanus might form hybrids with other southern African Schoenus species, but this needs to be confirmed by further studies. [1]

Taxonomy

Schoenus dregeanus is a species in family Cyperaceae, tribe Schoeneae. [2] Other notable genera in tribe Schoeneae are Costularia, Gahnia , Lepidosperma , Oreobolus and Tetraria . [2] [4] [5] Schoenus dregeanus is most closely related to other southern African Schoenus species, especially species in the Epischoenus group. [1]

The genus Tetraria once included species from the southern African Schoenus; however, we now know that the two groups are evolutionary distinct based on molecular and morphological differences. [6] To ensure that this group of sedges is monophyletic (i.e. the genus only has closely related species), several species of the southern African Tetraria and Epischoenus were transferred into Schoenus. [6] The southern African Schoenus can be distinguished from Tetraria species in the field by their lack of stem leaves and the absence of reticulate sheaths at the bases of the flowering stems. [6]

Distribution and habitat

Schoenus dregeanus has been mostly observed from the Cederberg and Worcester areas of South Africa, with additional collections from the Riviersonderend Mountains and the Prince Albert region. [1] This species tends to occur on moist, mountainous habitats sites between 600 and 1400 metres in elevation, and it can sometimes dominate the vegetation in moist areas. [1]

Related Research Articles

<i>Schoenus quartziticus</i> Species of grass-like plant

Schoenus quartziticus is a species of sedge endemic to the Agulhas Plain region of the Western Cape Province in southern South Africa.

<i>Schoenus arenicola</i> Species of grass-like plant

Schoenus arenicola is a species of sedge endemic to the south-west coast of South Africa.

<i>Schoenus pictus</i> Species of grass-like plant

Schoenus pictus is a species of sedge endemic to the Western Cape Province of South Africa. It is a species usually found on mountain slopes.

<i>Schoenus megacarpus</i> Species of grass-like plant

Schoenus megacarpus is a species of sedge endemic to the south-central region of South Africa.

<i>Schoenus auritus</i> Species of grass-like plant

Schoenus auritus is a species of sedge endemic to southern and eastern South Africa.

<i>Schoenus ligulatus</i> Species of grass-like plant

Schoenus ligulatus is a species of sedge endemic to the western regions of the Western Cape Province of South Africa.

<i>Schoenus exilis</i> Species of grass-like plant

Schoenus exilis is a species of sedge endemic to the western areas of the Western Cape Province of South Africa.

<i>Schoenus bolusii</i> Species of grass-like plant

Schoenus bolusii is a species of sedge endemic to the mountains of the Western Cape Province of South Africa. However, S. bolusii is not found on the Cape Peninsula.

<i>Schoenus submarginalis</i> Species of grass-like plant

Schoenus submarginalis is a species of sedge endemic to the mountains of the Western and Eastern Cape provinces of South Africa.

<i>Schoenus crassiculmis</i> Species of grass-like plant

Schoenus crassiculmis is a species of sedge endemic to the mountains of the Western Cape Province of South Africa. Few collections of this species have also been made from western areas of the Eastern Cape Province.

<i>Schoenus crassus</i> Species of grass-like plant

Schoenus crassus is a species of sedge endemic to south-western South Africa.

<i>Schoenus galpinii</i> Species of grass-like plant

Schoenus galpinii is a species of sedge endemic to eastern southern Africa.

<i>Schoenus adnatus</i> Species of grass-like plant

Schoenus adnatus is a species of sedge endemic to mountainous locations in southern regions of South Africa.

<i>Schoenus complanatus</i> Species of grass-like plant

Schoenus complanatus is a species of sedge endemic to the western mountains of the Western Cape Province of South Africa.

<i>Schoenus gracillimus</i> Species of grass-like plant

Schoenus gracillimus is a species of sedge endemic to the Western Cape Province of South Africa.

<i>Schoenus lucidus</i> Species of grass-like plant

Schoenus lucidus is a species of sedge endemic to the western mountains of the Western Cape Province of South Africa.

<i>Schoenus neovillosus</i> Species of grass-like plant

Schoenus neovillosus is a species of sedge endemic to the south-western mountains of the Western Cape Province of South Africa.

<i>Schoenus graciliculmis</i> Species of grass-like plant

Schoenus graciliculmis is a species of sedge endemic to regions of the southern Eastern Cape Province and nearby regions of the Western Cape Province of South Africa.

<i>Schoenus inconspicuus</i> Species of grass-like plant

Schoenus inconspicuus is a species of sedge endemic to south-western areas of the Western Cape Province of South Africa.

<i>Schoenus crinitus</i> Species of grass-like plant

Schoenus crinitus is a species of sedge endemic to the Worcester region of the Western Cape Province of South Africa.

References

  1. 1 2 3 4 5 6 7 8 9 10 11 12 13 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: 296–316. doi: 10.1016/j.sajb.2020.08.029 .
  2. 1 2 3 4 Elliott, T.L.; Barrett, R.L.; Muasya, A.M. (2019). "A taxonomic revision of Schoenus cuspidatus and allies (Cyperaceae, tribe Schoeneae)—Part 1". South African Journal of Botany. 121: 519–535. doi: 10.1016/j.sajb.2018.11.021 .
  3. Levyns, M. (1947). "Tetraria and related genera, with special reference to the flora of the Cape Peninsula". Journal of South African Botany. 13: 73–93.
  4. Viljoen, J.-A.; Muasya, A.M.; Barrett, R.L.; Bruhl, J.J.; Gibbs, A.K.; Slingsby, J.A.; Wilson, K. L.; Verboom, G.A. (2013). "Radiation and repeated transoceanic dispersal of Schoeneae (Cyperaceae) through the southern hemisphere". American Journal of Botany. 100 (12): 2494–2508. doi:10.3732/ajb.1300105.
  5. Larridon, I.; Bauters, K.; Semmouri, I.; Viljoen, J.-A.; Prychid, C.J.; Muasya, A.M.; Bruhl, J.J.; Wilson, K.L.; Senterre, B.; Goetghebeur, P. (2018). "Molecular phylogenetics of the genus Costularia (Schoeneae, Cyperaceae) reveals multiple distinct evolutionary lineages". Molecular Phylogenetics and Evolution. 126: 196–209. doi:10.1016/j.ympev.2018.04.016.
  6. 1 2 3 Elliott, T.L.; Muasya, A.M. (2017). "Taxonomic realignment in the southern African Tetraria (Cyperaceae, tribe Schoeneae; Schoenus clade)". South African Journal of Botany. 112: 354–360. doi: 10.1016/j.sajb.2017.06.011 .