Dataset Information

Evidence for coal forest refugia in the seasonally dry Pennsylvanian tropical lowlands of the Illinois Basin, USA.

ABSTRACT: The Moscovian plant macroflora at Cottage Grove southeastern Illinois, USA, is a key example of Pennsylvanian (323-299 Million years ago) dryland vegetation. There is currently no palynological data from the same stratigraphic horizons as the plant macrofossils, leaves and other vegetative and reproductive structures, at this locality. Consequently, reconstructions of the standing vegetation at Cottage Grove from these sediments lack the complementary information and a more regional perspective that can be provided by sporomorphs (prepollen, pollen, megaspores and spores). In order to provide this, we have analysed the composition of fossil sporomorph assemblages in two rock samples taken from macrofossil-bearing inter-coal shale at Cottage Grove. Our palynological data differ considerably in composition and in the dominance-diversity profile from the macrofossil vegetation at this locality. Walchian conifers and pteridosperms are common elements in the macroflora, but are absent in the sporomorph assemblages. Reversely, the sporomorph assemblages at Cottage Grove comprise 17 spore taxa (?16% and ?63% of the total assemblages) that are known from the lycopsid orders Isoetales, Lepidodendrales and Selaginallales, while Cottage Grove's macrofloral record fails to capture evidence of a considerable population of coal forest lycopsids. We interpret our results as evidence that the Pennsylvanian dryland glacial landscape at Cottage Grove included fragmented populations of wetland plants living in refugia.

SUBMITTER: Looy CV

PROVIDER: S-EPMC4226648 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature

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Evidence for coal forest refugia in the seasonally dry Pennsylvanian tropical lowlands of the Illinois Basin, USA.

Looy Cindy V CV Stevenson Robert A RA Van Hoof Thomas B TB Mander Luke L

PeerJ 20141104

The Moscovian plant macroflora at Cottage Grove southeastern Illinois, USA, is a key example of Pennsylvanian (323-299 Million years ago) dryland vegetation. There is currently no palynological data from the same stratigraphic horizons as the plant macrofossils, leaves and other vegetative and reproductive structures, at this locality. Consequently, reconstructions of the standing vegetation at Cottage Grove from these sediments lack the complementary information and a more regional perspective ...[more]

PMID: 25392752

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Dataset Information

Evidence for coal forest refugia in the seasonally dry Pennsylvanian tropical lowlands of the Illinois Basin, USA.

Publications

Evidence for coal forest refugia in the seasonally dry Pennsylvanian tropical lowlands of the Illinois Basin, USA.

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