Geminispermum

Name

Geminispermum

Rank

Genus

Authors (Pub.)

Friis E. M. Crane P. R. Pedersen K. R.  

Publication

Geminispermum, an Early Cretaceous (early–middle Albian) cupulate unit from the angiosperm-dominated Puddledock flora of eastern North America [2019/12]

Journal

Acta Palaeobotanica

Volume

59

Issue

2

Page number

230

Year

2019

Parent Taxon

[Class] Caytoniopsida

Fossil Status

reproductive organs

Type

Geminispermum virginiense

Diagnosis

Reproductive (ovulate) unit bisymmetrical consisting of a short axis bifurcating into two cupule-bearing stalks. Cupule-bearing stalks above bifurcation narrowly elliptical and bilaterally symmetrical in transverse section. Each cupule stalk in the axil of, and partially fused to, a prominent bract. Bract several cell layers thick and supplied by a single central vascular bundle. Each cupule stalk bearing a single one-seeded cupule and continuing distally beyond the attachment of the seed to form a broad transverse crest over the cupule apex. Cupule stalk supplied by two vascular bundles. Cupules recurved towards the center of the reproductive unit. Cupule nonvalvate, with parallel longitudinal ridges on its exposed surface and opening by a short transverse slit. Seed almost completely enclosed in the cupule, basally attached, orthotropous, free from cupule except at the base, triangular in transverse section. Micropyle positioned at the transverse slit and projecting only slightly. Nucellus free from the integument except at base. Resin bodies present in axes and bracts.