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Sökning: onr:"swepub:oai:DiVA.org:nrm-2880" > Tanispermum, a new ...

LIBRIS Formathandbok  (Information om MARC21)
FältnamnIndikatorerMetadata
00003987naa a2200505 4500
001oai:DiVA.org:nrm-2880
003SwePub
008181017s2018 | |||||||||||000 ||eng|
024a https://urn.kb.se/resolve?urn=urn:nbn:se:nrm:diva-28802 URI
024a https://doi.org/10.1002/ajb2.11242 DOI
040 a (SwePub)nrm
041 a engb eng
042 9 SwePub
072 7a ref2 swepub-contenttype
072 7a art2 swepub-publicationtype
100a Friis, Else Marieu Naturhistoriska riksmuseet,Enheten för paleobiologi4 aut0 (Swepub:nrm)elsefrii
2451 0a Tanispermum, a new genus of distinctive hemi-orthotropous to hemi-anatropous angiosperm seeds from the Early Cretaceous of eastern North America
264 c 2018-08-06
264 1a USA :b Wiley,c 2018
338 a electronic2 rdacarrier
520 a PREMISE OF THE STUDY:Exotestal seeds with characters that indicate relationship to extant Austrobaileyales and Nymphaeales are abundant in Early Cretaceous sediments from Portugal and eastern North America, but their variety and unique features provide evidence of extensive extinct diversity among early angiosperms.METHODS:The fossils were extracted from Early Cretaceous sediments from Virginia and Maryland, United States, by sieving in water. After cleaning with HF, HCl and water, they were examined using SEM and SRXTM and compared to seeds of extant and fossil angiosperms.KEY RESULTS:A new genus, Tanispermum gen. nov., with four species (T. hopewellense sp. nov., T. marylandense sp. nov., T. drewriense sp. nov., and T. antiquum sp. nov.) is recognized. Relationship with extant Austrobaileyales and Nymphaeales is indicated by an exotesta of tall palisade sclerenchyma with undulate anticlinal walls forming a jigsaw puzzle-like surface pattern. However, seeds of Tanispermum differ from those of Austrobaileyales and Nymphaeales in their hemi-orthotropous-hemi-anatropous organization. Attempts to place Tanispermum in a phylogenetic context confront a variety of problems, including lack of information on other parts of these extinct plants.CONCLUSIONS:The discovery highlights the extent to which the morphology of extant angiosperms is not representative of the diversity that once existed among early-diverging members of the group. The relictual nature of extant taxa near the base of the angiosperm tree greatly complicates the reconstruction of ancestral character states and emphasizes the need for focused paleobotanical studies to elucidate the extinct diversity that existed early in angiosperm evolution.
650 7a NATURVETENSKAPx Geovetenskap och miljövetenskapx Annan geovetenskap och miljövetenskap0 (SwePub)105992 hsv//swe
650 7a NATURAL SCIENCESx Earth and Related Environmental Sciencesx Other Earth and Related Environmental Sciences0 (SwePub)105992 hsv//eng
653 a SRXTM
653 a Tanispermum
653 a Austrobaileyales
653 a Early Cretaceous
653 a Nymphaeales
653 a exotestal
653 a fossil angiosperms
653 a fossil seeds
653 a mesofossils
653 a synchrotron radiation X-ray tomographic microscopy
653 a Ecosystems and species history
653 a Ekosystem och arthistoria
653 a Diversity of life
653 a Livets mångfald
700a Crane, Peter Robertu Oak Spring Garden Foundation, Virginia, USA4 aut
700a Pedersen, Kaj Raunsgaardu Århus University, Denmark4 aut
710a Naturhistoriska riksmuseetb Enheten för paleobiologi4 org
773t American Journal of Botanyd USA : Wileyg 105, s. 1369-1388q 105<1369-1388x 0002-9122x 1537-2197
856u https://nrm.diva-portal.org/smash/get/diva2:1256528/FULLTEXT01.pdfx primaryx Raw objecty fulltext:print
856u https://bsapubs.onlinelibrary.wiley.com/doi/pdfdirect/10.1002/ajb2.1124
8564 8u https://urn.kb.se/resolve?urn=urn:nbn:se:nrm:diva-2880
8564 8u https://doi.org/10.1002/ajb2.1124

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