Mesozoic Diversity of Osmundaceae: Osmundacaulis whittlesii sp. nov. in the Early Cretaceous of Western Canada

Abstract

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The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

“…References: Bower (1926), Gould (1973), Herbst (2003, 2008, 2015), Kidston & Gwynne-Vaughan (1907), Miller (1971), Penhallow (1902a, 1902b), Schelpe (1955, 1956), Smith, Rothwell & Stockey (2015), Tidwell (1986, 1987, 1990, 2002), Tidwell & Jones (1987) and Tidwell & Pigg (1993).…”

Burmese amber fossils bridge the gap in the Cretaceous record of polypod ferns

“…Precursors of this hypothesis were introduced before the advent of DNA based dating (Lovis, 1977;Rothwell, 1996;Smith, 1972), but were challenged by the rarity of Cretaceous fossils of Polypodiales (Collinson, 1996(Collinson, , 2001Skog, 2001). This pattern is unlikely to be explained by rock bias against the preservation of ferns because Jurassic and Cretaceous fossils are known for many other fern lineages such as Cyatheales, Gleicheniales, Osmundales, Salviniales, and Schizaeales (Hu & Taylor, 2014;Kvacek et al 2006;Mohr et al, 2015;Skog 2001;Smith et al, 2003;Smith et al, 2015;Tidwell and Ash, 1994;Vera and Herbst, 2015). As pointed out in studies on the spore record of ferns (Nagalingum et al, 2002), the microfossil record suggests a decline of ferns in the late Mesozoic instead of the Cretaceous to Eocene radiation suggested by DNA-based divergence time estimates (Schneider et al, 2004).…”