The diversity of Australian Mesozoic bennettitopsid reproductive organs
2018 (English)In: Palaeobiodiversity and Palaeoenvironments, ISSN 1867-1594, E-ISSN 1867-1608, Vol. 98, p. 71-95Article in journal (Refereed) Published
Abstract [en]
Several dispersed reproductive organs of bennettitopsid gymnosperms are described and illustrated from Triassic to Cretaceous strata of Australia: Williamsonia eskensis sp. nov. (Middle Triassic), Williamsonia ipsvicensis sp. nov. (Upper Triassic), Williamsonia durikaiensis sp. nov. (Lower Jurassic), Williamsonia sp. (Lower Jurassic), Williamsonia rugosa sp. nov. (Middle Jurassic), Williamsonia gracilis sp. nov. (Lower Cretaceous), Cycadolepis ferrugineus sp. nov. (Lower Jurassic), Cycadolepis sp. (Lower Cretaceous), and Fredlindia moretonensis Shirley 1898 comb. nov. (Upper Triassic). Among these, W. eskensis appears to represent the oldest bennettitalean reproductive structure yet identified. Although global floras expressed less provincialism during the Mesozoic and many genera are cosmopolitan, Australian bennettopsid species appear to have been endemic based on the morphological characters of the reproductive structures. Bennettopsids have a stratigraphic range of around 210 million years in Australia and are widely and abundantly represented by leaf fossils, but only around 20 specimens of reproductive structures, of which half are attributed to Fredlindia, have been recovered from that continent’s geological archive. The extremely low representation of reproductive organs vis-à-vis foliage is interpreted to reflect a combination of physical disintegration of the seed-bearing units while attached to the host axis and, potentially, extensive vegetative reproduction in bennettopsids growing at high southern latitudes during the Mesozoic.
Place, publisher, year, edition, pages
Berlin, 2018. Vol. 98, p. 71-95
Keywords [en]
Bennettitales, Fredlindiales, Reproductive biology, Floral diversity, New species, Williamsonia
National Category
Other Earth and Related Environmental Sciences
Research subject
The changing Earth
Identifiers
URN: urn:nbn:se:nrm:diva-2900DOI: 10.1007/s12549-017-0286-zOAI: oai:DiVA.org:nrm-2900DiVA, id: diva2:1257817
Funder
Swedish Research Council, 2014-5234Swedish Research Council, 2012-4375
Note
Other funding from:
National Science Foundation (project #1636625)
German Research Council (DFG KR2125/3)
Friends of the Swedish Museum of Natural History (Riksmusei Vänner, Stockholm)
SYNTHESYS (AT-TAF 467)
2018-10-222018-10-22Bibliographically approved