Earliest Triassic origin of Isoetes and quillwort evolutionary radiation
Isoetes beestonii new species is the most ancient known species of this living genus. In earliest Triassic shales of the Sydney and Bowen Basins of Australia it is locally abundant as circlets of transversely wrinkled leaves. It was heterosporous with megaspores of Maiturisporites rewanensis and mic...
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Online Access: | http://dx.doi.org/10.1017/s0022336000039524 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022336000039524 |
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crcambridgeupr:10.1017/s0022336000039524 2024-06-23T07:53:24+00:00 Earliest Triassic origin of Isoetes and quillwort evolutionary radiation Retallack, Gregory J. 1997 http://dx.doi.org/10.1017/s0022336000039524 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022336000039524 en eng Cambridge University Press (CUP) https://www.cambridge.org/core/terms Journal of Paleontology volume 71, issue 3, page 500-521 ISSN 0022-3360 1937-2337 journal-article 1997 crcambridgeupr https://doi.org/10.1017/s0022336000039524 2024-06-12T04:04:03Z Isoetes beestonii new species is the most ancient known species of this living genus. In earliest Triassic shales of the Sydney and Bowen Basins of Australia it is locally abundant as circlets of transversely wrinkled leaves. It was heterosporous with megaspores of Maiturisporites rewanensis and microspores of Lundbladispora sp. cf. L. springsurensis. Isoetes thus predates Pleuromeia from which it has been thought to have evolved. Australian Pleuromeia -like subarborescent lycopsids are here reviewed as whole plants, with names based on fertile structures, and include Cylostrobus sydneyensis Helby and Martin from the Sydney Basin, Pleuromeia dubia (Seward) Retallack from the Sydney and Canning Basins, and Cylostrobus indicus (Lele) new combination and Pleuromeia sternbergii (Münster) Corda for Germar, newly recorded from the Canning Basin. There are in addition an array of cormose lycopsids that formed compact conelike plants when fertile, intermediate in stature between Isoetes and Pleuromeia. One of these is Tomiostrobus australis (Ash) Sadovnikov, formerly regarded as a cone, but here reinterpreted as a small pioneering plant of oligotrophic lakes and ponds, like Isoetes. Its megaspores are Horstisporites and its microspores are the stratigraphically important Aratrisporites tenuispinosus. Other similar forms are Tomiostrobus polaris (Lundblad) new combination from the early Triassic of Greenland, T. mirabilis (Snigirevskaya) new combination from the early Triassic of the Tunguska Basin of Siberia, T. taimyrica (Sadovnikov) new combination from the Early Triassic of the Taimyr region of Siberia, Lepacyclotes ermayinensis (Wang) new combination from the middle Triassic of China, L. convexus (Brik) new combination from the middle-late Triassic of Kazachstan, and L. zeilleri (Fliche) new combination from the middle Triassic of France and Germany. The diversity of isoetaleans in early Triassic floras and the weak vascular system of permineralized Tomiostrobus and Pleuromeia contradict the traditional view that ... Article in Journal/Newspaper Greenland Taimyr Siberia Cambridge University Press Greenland Tunguska ENVELOPE(144.784,144.784,59.388,59.388) Brik ENVELOPE(-18.610,-18.610,66.120,66.120) Journal of Paleontology 71 3 500 521 |
institution |
Open Polar |
collection |
Cambridge University Press |
op_collection_id |
crcambridgeupr |
language |
English |
description |
Isoetes beestonii new species is the most ancient known species of this living genus. In earliest Triassic shales of the Sydney and Bowen Basins of Australia it is locally abundant as circlets of transversely wrinkled leaves. It was heterosporous with megaspores of Maiturisporites rewanensis and microspores of Lundbladispora sp. cf. L. springsurensis. Isoetes thus predates Pleuromeia from which it has been thought to have evolved. Australian Pleuromeia -like subarborescent lycopsids are here reviewed as whole plants, with names based on fertile structures, and include Cylostrobus sydneyensis Helby and Martin from the Sydney Basin, Pleuromeia dubia (Seward) Retallack from the Sydney and Canning Basins, and Cylostrobus indicus (Lele) new combination and Pleuromeia sternbergii (Münster) Corda for Germar, newly recorded from the Canning Basin. There are in addition an array of cormose lycopsids that formed compact conelike plants when fertile, intermediate in stature between Isoetes and Pleuromeia. One of these is Tomiostrobus australis (Ash) Sadovnikov, formerly regarded as a cone, but here reinterpreted as a small pioneering plant of oligotrophic lakes and ponds, like Isoetes. Its megaspores are Horstisporites and its microspores are the stratigraphically important Aratrisporites tenuispinosus. Other similar forms are Tomiostrobus polaris (Lundblad) new combination from the early Triassic of Greenland, T. mirabilis (Snigirevskaya) new combination from the early Triassic of the Tunguska Basin of Siberia, T. taimyrica (Sadovnikov) new combination from the Early Triassic of the Taimyr region of Siberia, Lepacyclotes ermayinensis (Wang) new combination from the middle Triassic of China, L. convexus (Brik) new combination from the middle-late Triassic of Kazachstan, and L. zeilleri (Fliche) new combination from the middle Triassic of France and Germany. The diversity of isoetaleans in early Triassic floras and the weak vascular system of permineralized Tomiostrobus and Pleuromeia contradict the traditional view that ... |
format |
Article in Journal/Newspaper |
author |
Retallack, Gregory J. |
spellingShingle |
Retallack, Gregory J. Earliest Triassic origin of Isoetes and quillwort evolutionary radiation |
author_facet |
Retallack, Gregory J. |
author_sort |
Retallack, Gregory J. |
title |
Earliest Triassic origin of Isoetes and quillwort evolutionary radiation |
title_short |
Earliest Triassic origin of Isoetes and quillwort evolutionary radiation |
title_full |
Earliest Triassic origin of Isoetes and quillwort evolutionary radiation |
title_fullStr |
Earliest Triassic origin of Isoetes and quillwort evolutionary radiation |
title_full_unstemmed |
Earliest Triassic origin of Isoetes and quillwort evolutionary radiation |
title_sort |
earliest triassic origin of isoetes and quillwort evolutionary radiation |
publisher |
Cambridge University Press (CUP) |
publishDate |
1997 |
url |
http://dx.doi.org/10.1017/s0022336000039524 https://www.cambridge.org/core/services/aop-cambridge-core/content/view/S0022336000039524 |
long_lat |
ENVELOPE(144.784,144.784,59.388,59.388) ENVELOPE(-18.610,-18.610,66.120,66.120) |
geographic |
Greenland Tunguska Brik |
geographic_facet |
Greenland Tunguska Brik |
genre |
Greenland Taimyr Siberia |
genre_facet |
Greenland Taimyr Siberia |
op_source |
Journal of Paleontology volume 71, issue 3, page 500-521 ISSN 0022-3360 1937-2337 |
op_rights |
https://www.cambridge.org/core/terms |
op_doi |
https://doi.org/10.1017/s0022336000039524 |
container_title |
Journal of Paleontology |
container_volume |
71 |
container_issue |
3 |
container_start_page |
500 |
op_container_end_page |
521 |
_version_ |
1802645011665256448 |