Biology:Schoenus pictus

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Schoenus pictus
Schoenus pictus-growth-form.jpg
Yellow veldrush
Scientific classification edit
Kingdom: Plantae
Clade: Tracheophytes
Clade: Angiosperms
Clade: Monocots
Clade: Commelinids
Order: Poales
Family: Cyperaceae
Genus: Schoenus
Species:
S. pictus
Binomial name
Schoenus pictus
(Boeckeler) Kuntze
Spictus-map.jpg
Documented collection localities in South Africa
Synonyms[1]
  • Elynanthus pictus Boeckeler
  • Tetraria picta (Boeckeler) C.B.Clarke

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.

Diagnostic characters

Key diagnostic characters of S. pictus are its relatively firm and thick bracts that surrounding the flower clusters (spikes). These bracts are often yellow-brown in colour in young plants and they envelop the spikes.[1] In addition, the leaf sheaths and part of the flowering stems are usually sticky.[1]

The prominent bracts surrounding the spikes combined with the sticky (viscous) leaf bases distinguish S. pictus from other Southern African Schoenus species.

Similar to other sedges, plants in this group are very difficult to identify. It appears that part of this problem is caused by the tendency of the southern African Schoenus to form hybrids with each other.[2] However, hybridization is yet to be observed in S. pictus.[1]

Taxonomy

Schoenus pictus is a species in family Cyperaceae, tribe Schoeneae.[3] Other notable genera in tribe Schoeneae include Lepidosperma, Oreobolus, Costularia, Tetraria and Gahnia.[3][4][5] The most closely-related species to S. pictus are other southern African Schoenus species, specifically, species in the Schoenus compar - Schoenus pictus group.[1]

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

Distribution and ecology

Schoenus pictus grows throughout the western mountains of the Western Cape Province of South Africa. Most reports of this species are from high mountain slopes surrounded by fynbos vegetation, often from damp sites.[1]

Images

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 Elliott, T.L.; Muasya, A.M. (2018). "A taxonomic revision of Schoenus compar - Schoenus pictus and allies (Cyperaceae, tribe Schoeneae) with three new species described from South Africa". South African Journal of Botany 114: 303–315. doi:10.1016/j.sajb.2017.11.020. 
  2. 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. 
  3. 3.0 3.1 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. 
  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. et al. (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. 6.0 6.1 6.2 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. 

Wikidata ☰ Q69415392 entry