illustration credit: Joseph Rogers and Leo Ascarrunz (Interactive Geology Project, University of Colorado)
'Rhyniophytes'
Locality: Impofu Dam
Age: Early Devonian
'Rhyniophytes' are a paraphyletic group representing an intermediate evolutionary grade between non-vascular and the rest of vascular plants (1, 2). Among them, Cooksonia is regarded as the most primitive and is the oldest confirmed vascular plant, dating from the middle of the Silurian to the end of the Early Devonian. Three species of Cooksonia are recorded at the Impofu Dam site: Cooksonia paranensis, Cf. Cooksonia hemisphaerica and Cooksonia cambrensis (3).
Several other known 'rhyniophyte' species are recognised at the site: Steganotheca striata, Aberlemnia caledonica, Tortilicaulis sp., Uskiella spargens, Yarravia oblonga.
Three new genera and species were also described: Krommia parvapila, Elandia itshoba and Mtshaelo kougaensi (Gess and Prestianni 2021).
Locality: Impofu Dam
Age: Early Devonian
'Rhyniophytes' are a paraphyletic group representing an intermediate evolutionary grade between non-vascular and the rest of vascular plants (1, 2). Among them, Cooksonia is regarded as the most primitive and is the oldest confirmed vascular plant, dating from the middle of the Silurian to the end of the Early Devonian. Three species of Cooksonia are recorded at the Impofu Dam site: Cooksonia paranensis, Cf. Cooksonia hemisphaerica and Cooksonia cambrensis (3).
Several other known 'rhyniophyte' species are recognised at the site: Steganotheca striata, Aberlemnia caledonica, Tortilicaulis sp., Uskiella spargens, Yarravia oblonga.
Three new genera and species were also described: Krommia parvapila, Elandia itshoba and Mtshaelo kougaensi (Gess and Prestianni 2021).
References
1. Lang, W.H. (1937), "On the plant-remains from the Downtonian of England and Wales", Philosophical Transactions of the Royal Society B, 227 (544): 245–291
2. Taylor, E. L., Taylor, T. N., & Krings, M. (2009). Paleobotany: the biology and evolution of fossil plants. Academic Press.
3. Gess, R.W., & Prestianni, C. (2021). An early Devonian flora from the Baviaanskloof Formation (Table Mountain Group) of South Africa. Scientifc Reports, 11:11
1. Lang, W.H. (1937), "On the plant-remains from the Downtonian of England and Wales", Philosophical Transactions of the Royal Society B, 227 (544): 245–291
2. Taylor, E. L., Taylor, T. N., & Krings, M. (2009). Paleobotany: the biology and evolution of fossil plants. Academic Press.
3. Gess, R.W., & Prestianni, C. (2021). An early Devonian flora from the Baviaanskloof Formation (Table Mountain Group) of South Africa. Scientifc Reports, 11:11