Janegraya

Janegraya; Temporal range:
	Holotype of Janegraya sibylla, from Douglas Lake Member of Lenoir Limestone, at Douglas Dam, Tennessee[1]
Scientific classification
Kingdom:	Plantae
Division:	Marchantiophyta
Class:	Marchantiopsida
Order:	Sphaerocarpales
Family:	Sphaerocarpaceae
Genus:	†Janegraya; Retallack (2019)[1]
Type species
	Janegraya sibylla; Retallack (2019)

Janegraya is a genus of fossil with controversial interpretation from the Middle Ordovician (Darriwilian, 460 million years old) Douglas Lake Member of the Lenoir Limestone from Douglas Dam Tennessee.[1] The generic name honors Jane Gray, and the epithet means "prophetess".

Interpretative sketch of Janegraya sibylla

Periant around spore masses of 'Janegraya sibylla

Spore of Janegraya sibylla

Description

Janegraya is considered as a minute fossil balloonwort (Sphaerocarpaceae) by Gregory Retallack, and similar to living Sphaerocarpos. Its spores are permanent tetrads closed within a thin perine, widely known among Ordovician dispersed spores as Tetrahedraletes.[2]

Biological affinities

The interpretation of this fossil as an Ordovician example of Sphaerocarpaceae has been questioned in some quarters [3] but accepted in others.[4]

References

Retallack, G.J. (2019). "Ordovician land plants and fungi from Douglas Dam, Tennessee". The Palaeobotanist. 68: 1–33.
Wellman, Charles H.; Cascales-Miñana, Borja; Servais, Thomas (2023). "Terrestrialization in the Ordovician". Geological Society, London, Special Publications. 532 (1): 1–20. doi:10.1144/SP532-2022-92. S2CID 253011815.
Edwards, Dianne; Morris, Jennifer L.; Axe, Lindsey; Duckett, Jeffrey G.; Pressel, Silvia; Kenrick, Paul (2022). "Piecing together the eophytes – a new group of ancient plants containing cryptospores". New Phytologist. 233 (3): 1440–1455. doi:10.1111/nph.17703. ISSN 0028-646X. S2CID 244495761.
Leigh, Egbert (2022). "Fossil soils: trace fossils of ecosystems on land and windows on the context of evolution". Evolution Education and Outreach. 15:14: 1–5. doi:10.1186/s12052-022-00173-3. S2CID 255483235.

This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.

[Retallack_2019-1] Retallack, G.J. (2019). "Ordovician land plants and fungi from Douglas Dam, Tennessee". The Palaeobotanist. 68: 1–33.

[2] Wellman, Charles H.; Cascales-Miñana, Borja; Servais, Thomas (2023). "Terrestrialization in the Ordovician". Geological Society, London, Special Publications. 532 (1): 1–20. doi:10.1144/SP532-2022-92. S2CID 253011815.

[3] Edwards, Dianne; Morris, Jennifer L.; Axe, Lindsey; Duckett, Jeffrey G.; Pressel, Silvia; Kenrick, Paul (2022). "Piecing together the eophytes – a new group of ancient plants containing cryptospores". New Phytologist. 233 (3): 1440–1455. doi:10.1111/nph.17703. ISSN 0028-646X. S2CID 244495761.

[4] Leigh, Egbert (2022). "Fossil soils: trace fossils of ecosystems on land and windows on the context of evolution". Evolution Education and Outreach. 15:14: 1–5. doi:10.1186/s12052-022-00173-3. S2CID 255483235.