Fig 5 - uploaded by Stephen Mcloughlin
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Transverse section of the Early Jurassic Osmundaceae (Royal Fern) rhizome from Korsaröd showing a small central stem surrounded by numerous frond bases and intertwining roots. Field of view equals 3cm.
Source publication
On some occasions, it is the hard sweat and toil of palaeontologists labouring in the field at carefully planned excavation sites that yields the prize specimen on which careers are built. On other occasions, it is the chance discovery by an amateur collector that may yield that special fossil. We present an account of one such remarkable fossil di...
Context in source publication
Context 1
... the beds were indeed of Early Jurassic age. Among the many samples of volcanic rock and fossil wood that Gustav Andersson sent to Hans Tralau was a single peculiar petrified fern rhizome (Fig. 4). Tralau clearly recognised the significance of this fossil because he prepared several thin sections and took a series of photographs of the specimen (Fig. 5). Undoubtedly, Tralau intended to publish a formal description of this fossil, but his untimely death in March 1977 meant that the project was never completed. Archival correspondence at the Swedish Museum of Natural History reveals that, some years later, Britta Lundblad, then head of the Palaeobotany Department, exchanged letters with ...
Citations
... This fossil has proven useful for understanding the stasis in ploidy levels within Osmundaceae over the past 180 million years (Bomfleur et al., 2014), for resolving the relationships of fossil and extant representatives of the family (Bomfleur et al., 2015), and for evaluating the timing of cladogenesis within this group of ferns (Grimm et al., 2015). This unique specimen has also been the subject of popular science articles that outline its significance and history of discovery (McLoughlin et al., 2014b; Vajda et al., 2014). The fossil fern is further investigated here for evidence of interactions with other organisms in its environment. ...
A remarkably well permineralized osmundaceous rhizome from the Early Jurassic of southern Sweden yields evidence of an array of interactions with other organisms in its immediate environment. These include epiphytism by a herbaceous heterosporous lycopsid; putative oribatid mite herbivory and detritivory (petiole and detritus borings and coprolites); potential pathogenic, saprotrophic or mycorrhizal interactions between fungi and the host plant and its epiphytes; parasitism or saprotrophy by putative peronosporomycetes; and opportunistic or passive mycophagy by oribatid mites evidenced by fungal spores in coprolites. A combination of abrupt burial by lahar deposits and exceedingly rapid permineralization by precipitation of calcite from hydrothermal brines facilitated the exquisite preservation of the rhizome and its component community of epiphytes, herbivores, saprotrophs and parasites. Ancient ferns with a rhizome cloaked by a thick mantle of persistent leaf bases and adventitious roots have a high potential for preserving macro-epiphytes and associated micro-organisms, and are especially promising targets for understanding the evolution of biotic interactions in forest understorey ecosystems.
