Corystospermaceae

Corystospermaceae
Temporal range: Late Permian–Early Jurassic
Reconstruction of the Dicroidium plant (top right) in an Early Triassic Australian landscape. Art by Michael Rothman
Scientific classification Edit this classification
Kingdom: Plantae
Clade: Tracheophytes
Clade: Spermatophyta
Order: †Corystospermales
Petriella, 1981
Family: †Corystospermaceae
Thomas, 1933
Genera

See text

Synonyms
  • Ptilozamitaceae Němejc, 1950
  • Umkomasiaceae Petriella, 1981
  • Zuberiaceae Němejc, 1968

Corystosperms are a group of extinct seed plants (often referred to as "seed ferns") belonging to the family Corystospermaceae (also called Umkomasiaceae) assigned to the order Corystospermales[1] or Umkomasiales.[2][3] They were first described based on fossils collected by Hamshaw Thomas from the Burnera Waterfall locality near the Umkomaas River of South Africa.[4] Corystosperms are typified by a group of plants that bore forked Dicroidium leaves, Umkomasia cupulate ovulate structures and Pteruchus pollen organs, which grew as trees that were widespread over Gondwana during the Middle and Late Triassic. Other fossil Mesozoic seed plants with similar leaf and/or reproductive structures have also sometimes been included within the "corystosperm" concept sensu lato, such as the "doyleoids" from the Early Cretaceous of North America and Asia.[3] A potential corystosperm sensu lato, the leaf genus Komlopteris, is known from the Eocene of Tasmania, around 53-50 million years old, over 10 million years after the Cretaceous–Paleogene extinction event.[5]

  1. ^ Abu Hamad, A.; Blomenkemper, P.; Kerp, H.; Bomfleur, B. (December 2017). "Dicroidium bandelii sp. nov. (corystospermalean foliage) from the Permian of Jordan". PalZ. 91 (4): 641–648. Bibcode:2017PalZ...91..641A. doi:10.1007/s12542-017-0384-2. ISSN 0031-0220. S2CID 90520943.
  2. ^ Doweld, Alexander B. (2001). Prosyllabus Tracheophytorum: Tentamen systematis plantarum vascularium (in English and Russian). Moscow: GEOS.
  3. ^ a b Shi, Gongle; Herrera, Fabiany; Herendeen, Patrick S.; Clark, Elizabeth G.; Crane, Peter R. (2022-12-31). "Silicified cupulate seed-bearing structures from the Early Cretaceous of eastern Inner Mongolia, China: rethinking the corystosperm concept". Journal of Systematic Palaeontology. 20 (1): 1–33. doi:10.1080/14772019.2022.2133644. ISSN 1477-2019. S2CID 253562726.
  4. ^ Thomas, H.H. (1933). "On some pteridospermous plants from the Mesozoic rocks of South Africa". Philosophical Transactions of the Royal Society B. 222 (483–493): 193–265. doi:10.1098/rstb.1932.0016.
  5. ^ McLoughlin, Stephen; Carpenter, Raymond J.; Jordan, Gregory J.; Hill, Robert S. (2008). "Seed ferns survived the end-Cretaceous mass extinction in Tasmania". American Journal of Botany. 95 (4): 465–471. doi:10.3732/ajb.95.4.465. ISSN 1537-2197. PMID 21632371.