Harmsvernia hydrocotyloidea Postnikoff nom. illeg.

Plant Fossil Names Registry Number: PFN001961

Act LSID: urn:lsid:plantfossilnames.org:act:1961

Author: A. C. L. Postnikoff

Rank: species

Genus: Harmsvernia Postnikoff

Illegitimate name

Reference: Postnikoff, A. C. L. (2009): Flora of the Ravenscrag Formation of the Big Muddy valley, Willow Bunch Lake map area (72H), Saskatchewan. University of Saskatchewan: 1–230., link

Page of description: 77

Previously published illustration or figures: p. 45, fig. 1 in McIver, E. E. & Basinger, J. F. (1993): Flora of the Ravenscrag Formation (Paleocene), southwestern Saskatchewan, Canada. – Palaeontographica Canadiana 10: 1–167.

Replaced synonym

Original diagnosis/description

Leaves orbiculate, peltate, up to 8.5 cm in diameter; margin shallowly and regularly dentate; teeth mainly of one size, up to 15 mm wide, may be slightly larger where primary veins reach margin, smaller where secondary veins reach margin; glandular, glands forming thickenings at teeth apices where primary of secondary veins reach margin; texture membranous or chartaceous. Venation actinodromous. Primary veins eight, moderate in size, radiating from centre of leaf; course straight, becoming more irregular towards margin. Secondary veins moderate to thin in size, arising from primaries at angles of about 45°, becoming weaker and looping towards margin, joining superadjacent secondaries or reaching margin through centre of teeth. Tertiary veins moderate to weak in size, arising from secondaries at angles of 30–45°, pattern orthogonal reticulate, arrangement opposite and alternate in about equal proportions. Highest order of venation quaternary. Quaternary veins thin, orthogonal, forming areolae. Areolae quadrangular, very large, about 2.0 mm. Free-ending veinlets not known. Marginal venation looped, of fourth order.

Etymology

In reference to the resemblance to Hydrocotyle.

Stratigraphy

Paleogene, Paleocene
Paskapoo Formation

Locality

Canada
[Near the mouth of the Blindman River, Blackfalds], Alberta