Frond Characteristics Of Cyrillopteris (Ex. Odontopteris) Orbicularis (Halle) Comb. Et Emend. Nov.: New Evidence From The Permian Upper Shihezi (Upper Shihhotse) Formation Of North China
Abstract
Exceptionally well-preserved impression fossils of Cyrillopteris (ex. Odontopteris) orbicularis (Halle) comb. et emend. nov. have been described from the lower part of the middle–upper Permian Upper Shihezi (Upper Shihhotse) Formation in Yangquan City, Shanxi Province, North China. For the first time, this typical Cathaysian seed fern is confirmed to have a bipartite frond with two bipinnate branches, comparable with that of C. genuina (Grand'Eury) Laveine et Oudoire from the Pennsylvanian of France. Entire-margined cyclopteriod elements occur in the proximal portion of the long petiole. With increasing proximity of the bifurcation, the cyclopteroid elements progressively differentiate into pinnae with individual pinnules. True intercalary pinnules, which would be fully inserted on the primary rachides, are not present. Characteristics of our new specimens provide new information on the frond architecture of C. orbicularis (Halle) comb. et emend. nov., and allow a relatively complete circumscription of the overall features of this taxon, an emendation of the species diagnosis, and the presentation of an accurate frond reconstruction. Specimens of C. orbicularis comb. et emend. nov. are preserved with mesophytes and xerophytes from the same interval, demonstrating the vegetation in the research area grew under a seasonal subhumid to semiarid climates during the late Guadalupian.
Recommended Citation
M. Wan et al., "Frond Characteristics Of Cyrillopteris (Ex. Odontopteris) Orbicularis (Halle) Comb. Et Emend. Nov.: New Evidence From The Permian Upper Shihezi (Upper Shihhotse) Formation Of North China," Review of Palaeobotany and Palynology, vol. 324, article no. 105092, Elsevier, May 2024.
The definitive version is available at https://doi.org/10.1016/j.revpalbo.2024.105092
Department(s)
Geosciences and Geological and Petroleum Engineering
Keywords and Phrases
Cathaysia; Frond architecture; Odontopterids; Permian; Pteridosperm; Shanxi
International Standard Serial Number (ISSN)
0034-6667
Document Type
Article - Journal
Document Version
Citation
File Type
text
Language(s)
English
Rights
© 2024 Elsevier, All rights reserved.
Publication Date
01 May 2024
Comments
Youth Innovation Promotion Association of the Chinese Academy of Sciences, Grant 2020312