Cyathea cranhamii S.Y.Sm., G.W.Rothwell et Stockey
Plant Fossil Names Registry Number: PFN002658
Act LSID: urn:lsid:plantfossilnames.org:act:2658
Reference: Smith, S. Y., Rothwell, G. W. & Stockey, R. A. (2003): Cyathea cranhamii sp. nov. (Cyatheaceae), anatomically preserved tree fern sori from the Lower Cretaceous of Vancouver Island, British Columbia. – American Journal of Botany 90(5): 755–760., link
Page of description: 755
Illustrations or figures: figs 1–16
Holotype P13021 Hbot b, University of Alberta (UAPC-ALTA), Edmonton, Canada
Figures: figs 4–9, 11–13, 15, 16
Note: "bot" after "H" in inventory number is written in lower index.
Paratypes: P13018 Dbot a (not depicted), P13021 Hbot c (Figs. 1–3), and P13023 Abot (Figs. 10 and 14), housed in University of Alberta Paleobotanical Collections (UAPC-ALTA), Edmonton, Canada.
Tree fern with two rows of superficial sori beneath narrow pinnules. Sori with vascularized receptacle and sphaeropteroid indusium with distal slit-like opening, producing about 35 sporangia. Multicellular sporangial stalks of 5–6 cells in cross section, capsule up to 275–400 μm long, 200–300 μm wide, with annulus of approximately 20 cells and about 64 spores per sporangium. Spores 40–70 μm in diameter, triangular with concave interradial sides and rounded corners; arms of trilete extending three-quarters of the distance to periphery. Exospore approximately 650 nm thick; continuous perispore, with irregular sculpturing ranging from granulate/echinate to distinct rodlets.
The specific epithet cranhamii is proposed in recognition of Gerald Cranham, Parksville, British Columbia, Canada, who generously provided numerous plant specimens for study at the University of Alberta.
Cretaceous, Lower Cretaceous, Barremian
Longarm Formation equivalents
Apple Bay, Vancouver Island, British Columbia
Plant fossil remain
macro- and meso-fossils-embryophytes except wood