Biology:Uskiella

From HandWiki
Short description: Extinct genus of Devonian plants


Uskiella
Temporal range: Early Devonian
Scientific classification e
Kingdom: Plantae
Clade: Tracheophytes
Stem group: Rhyniophytes (?)
Genus: Uskiella
Shute & D.Edwards 1989[1]
Species

U. spargens Shute & D.Edwards 1989
U. reticulata Fanning et al. 1992

Uskiella is a genus of small fossil plants of Early Devonian age (around 420 to 390 million years ago). The diagnostic characters are naked axes branching isotomously, terminating in ellipsoidal, vertically elongate flat sporangia which split longitudinally into two valves.[1] Spores of U. reticulata have a reticulate appearance.[2] Coalified specimens have been reported from Wales,[2] with a possible occurrence in Australia.[1]

The relationships of the genus are not clear because many anatomical details remain unknown. In 2004, Crane et al. published a cladogram for the polysporangiophytes in which Uskiella is basal to the lycophytes (clubmosses and relatives).[3]

Hao and Xue in 2013 listed the genus as a rhyniophyte.[4]

References

  1. 1.0 1.1 1.2 Shute, C.H.; Edwards, D. (1989), "A new rhyniopsid with novel sporangium organization from the Lower Devonian of Wales", Botanical Journal of the Linnean Society 100 (2): 111–137, doi:10.1111/j.1095-8339.1989.tb01713.x 
  2. 2.0 2.1 Fanning, U.; Edwards, D.; Richardson, J.B. (1992), "A diverse assemblage of early land plants from the Lower Devonian of the Welsh Borderland", Botanical Journal of the Linnean Society 109 (2): 161–188, doi:10.1111/j.1095-8339.1992.tb00264.x 
  3. Crane, P.R.; Herendeen, P.; Friis, E.M. (2004), "Fossils and plant phylogeny", American Journal of Botany 91 (10): 1683–99, doi:10.3732/ajb.91.10.1683, PMID 21652317 
  4. Hao, Shougang; Xue, Jinzhuang (2013), The early Devonian Posongchong flora of Yunnan: a contribution to an understanding of the evolution and early diversification of vascular plants, Beijing: Science Press, p. 329, ISBN 978-7-03-036616-0, https://www.researchgate.net/publication/269875285, retrieved 2019-10-25 

Wikidata ☰ Q7902022 entry