Barykovia

Name

Barykovia

Rank

Genus

Authors (Pub.)

Moiseeva M. G.  

Publication

Barykovia, a new genus of angiosperms from the Campanian of northeastern Russia [2012/4]

Journal

Review of Palaeobotany and Palynology

Volume

178

Page number

2

Year

2012

Parent Taxon

[Class] Magnoliopsida

Fossil Status

leaves

Type

Barykovia tchucotica

Diagnosis

Leaves simple, entire, size varies from microphyll to notophyll, length to width ratio from 1.5:1 to 4:1. Leaf lamina oblong-ovate, narrow ovate or elliptical, sometimes asymmetric. Leaf base cuneate to broadly cuneate, rounded or rarely truncate, usually asymmetric and decurrent along petiole. Leaf apex acute, rarely acuminate or slightly rounded. Leaf margin serrate or dentate, double-serrate, double-dentate, rarely undulate, of regular or irregular spacing. Teeth large, typically broadly to less commonly narrow triangular, rounded-triangular, with straight to convex (occasionally slightly concave) apical and basal flanks and blunt or acute apices, with occasionally discerned small glands. Teeth vary in shape and size in one specimen, simple or compound with 1–3 smaller teeth on the basal side. Sinuses between teeth angular or rounded, sometimes both in one specimen. Petiole thin and short. Venation irregular pinnate, craspedodromous. Midvein straight or markedly curved. Secondary veins (5–11 pairs) deviate from midvein at 30–40° in the upper part and 70–80° in the basal part of lamina. Angles of divergence usually increasing basally, where secondaries recurved outside. Secondary veins irregularly spaced, often nonparallel, some of them opposite, others alternate. Some of secondary veins have 1-3 basiscopic and one acroscopic branches, terminating in marginal teeth or sinuses. Sometimes there are short intersecondary veins. Tertiary veins irregularly alternate percurrent with sinuous course.