Osmunda macrophylla Penh.

Plant Fossil Names Registry Number: PFN001926

Act LSID: urn:lsid:plantfossilnames.org:act:1926

Author: D. P. Penhallow

Rank: species

Reference: Penhallow, D. P. (1908): Report on Tertiary plants of British Columbia collected by Lawrence M. Lambe in 1906 together with a discussion of previously recorded Tertiary floras. Government Printing Bureau, Ottawa: 167 pp.

Page of description: 65

Illustrations or figures: fig. 15


Figures: fig. 15

Note: Penhallow (1908: Report on Tertiary plants of British Columbia, p. 65) described and figured (fig. 15) only one specimen of his new species. This specimen must be therefore regarded as the holotype. Penhallow (1908: 14) listed several collection housing the material from Red Deer River, but did not specify which species/specimens is housed in which collection.

Bell (1949: Bull. Geol. Surv. Canada, 13: 38, pl. 24, fig. 2, pl. 25, figs 1, 3, 4) designated 4 specimens from collection of Geological Survey, Canada (GSC P 6163–6166) as plesiotypes. But this designation can not be accepted as neotype designation, as only one specimen can be designated as neotype.

Original diagnosis/description

It could not be correlated with any previously observed Osmundas, although it may be identical with some one, particularly O. heeri. But the shape of the pinnules, and especially the breadth of their bases, seems to prohibit any such association. In the circumstances it has seemed better to assign it to a separate name, the justification for which appears in the apparently larger size of the fronds, as indicated by the width of the pinnules.

Emended diagnosis

Bell (1949: Bull. Geol. Surv. Canada, 13: 38):
Remarks. Frond, large, bipinnate. Pinnules. alternate, lanceolate; lower ones neuropteroid, with very short stalks of attachment and commonly more or less emarginate; more distal ones, sessile and more or less obliquely truncate at base; upper ones, attached by broad base, and inferior lowermost nerve originating in rachis; end pinnule, large and basally lobed. Apex of pinnules, bluntly acute; margin, finely crenulate. Midrib, fairly stout, continuous to, or bifurcate at, apex. Laterals, up to 20 pairs or more, about 45 degrees to midvein, pursuing nearly straight course to margin; lower ones divided close to origin, and each arm generally divided again before or near midcourse; upper ones divided once about midway; basal nerves divided about five times forming a fan wise group of branches.
The species is obviously close to, and perhaps conspecific with, Osmunda doroschkiana Goeppert. It is retained as a separate species only on account of the crenulate margins and the seemingly more divided basal nerves.


Paleogene, Paleocene
Paskapoo Formation

Paleocene according to Bell (1949: Bull. Geol. Surv. Canada, 13: 16), Penhallow (1908: Report on Tertiary plants of British Columbia, p. 14) assigned it to Eocene.


The Red Deer River at the mouth of the Blindman River near Blackfalds, Alberta

Plant fossil remain

macro- and meso-fossils-embryophytes except wood


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