Reconstruction and phylogenetic significance of a new Equisetum Linnaeus species from the Lower Jurassic of Cerro Bayo (Chubut province, Argentina)Show others and affiliations
2015 (English)In: Ameghiniana, ISSN 1851-8044, Vol. 52, p. 135-152Article in journal (Refereed) Published
Abstract [en]
We describe Equisetum dimorphum sp. nov. from the Lower Jurassic of Chubut Province, Patagonia, Argentina. This new species is based on fertile and vegetative remains preserved as impressions of stems, leaves, strobili, transversal sections of the stems showing their anatomy, and terminal pagoda-like structures. The fine-grained sedimentary matrix also preserved detailed impressions of epidermal features. The morphological characters allow a whole-plant reconstruction and assignment to Equisetum. Equisetum dimorphum sp. nov. shows a mosaic of morphological characters that are commonly present in other Mesozoic forms and representatives of the two extant Equisetum subgenera, e.g., sunken stomata and a blunt strobilus apex. Compared to other well-known Mesozoic equisetalean taxa, Equisetum dimorphum sp. nov. appears to be most closely related to a group of Jurassic Equisetum-like plants including Equisetum laterale Phillips and Equisetites ferganensis Seward. Additional evidence for the morphological stasis of the fertile and vegetative organs of extant horsetails is supplied with this new material, adding further support to the hypothesis that the extant horsetails are a successful group that has undergone only little morphological changeover time and that has been present, nearly worldwide, since Jurassic times.
Place, publisher, year, edition, pages
de Asociación Paleontológica Argentina , 2015. Vol. 52, p. 135-152
Keywords [en]
Equisetales, Equisetum, Systematic, Jurassic, Patagonia
National Category
Other Earth Sciences
Research subject
Ecosystems and species history
Identifiers
URN: urn:nbn:se:nrm:diva-1601DOI: 10.5710/AMGH.15.09.2014.2758OAI: oai:DiVA.org:nrm-1601DiVA, id: diva2:884948
Projects
VR 2014-5232 The evolutionary history of ferns
Funder
Swedish Research Council, VR 2014-52322015-12-172015-12-172025-02-07Bibliographically approved