Ephedrispermum tenuicostatum E.M.Friis, P.R.Crane et K.R.Pedersen

Plant Fossil Names Registry Number: PFN000207

Act LSID: urn:lsid:plantfossilnames.org:act:207

Authors: E. M. Friis, P. R. Crane & K. R. Pedersen

Rank: species

Genus: Ephedrispermum Rydin, K.R.Pedersen, P.R.Crane et E.M.Friis

Reference: Friis, E. M., Crane, P. R. & Pedersen, K. R. (2019): Chlamydospermous seeds document the diversity and abundance of extinct gnetalean relatives in Early Cretaceous vegetation. – International Journal of Plant Sciences 180(7): 643–666.

Page of description: 645

Illustrations or figures: figs 1, 2

Types

Original diagnosis/description

Seeds small and orthotropous, borne in the axils of opposite bracts. Integument free from seed envelope for its full length except at the base, where it is broadly attached. Integument apically extended into a long micropylar tube. Micropylar tube formed by an inner and an outer epidermis. Micropylar canal open apically, but entirely, or almost entirely, closed farther down by the cells of the inner epidermis that expand radially toward the center of the canal. Seed envelope ellipsoidal to almost spherical, four angled in transverse section in the apical part, circular to faintly four angled farther down. Surface of seeds with longitudinal ridges and dense transverse striations between the ridges that are formed by the narrow, transversely elongate cells of the outer sclerenchyma. Seed envelope extended in the micropylar region into a short collarlike central projection supporting the micropylar tube. Inner surface of seed envelope in the micropylar region without papillae. Inner epidermis of seed envelope of relatively large, longitudinally elongate, polygonal cellswith thin cell walls. Sclerenchyma zone of seed envelope with inner layer of narrow, transversely elongated cells, middle layer of longitudinally aligned cells, and outer layer of transversely aligned cells. Pollen in micropylar tube ephedroid, polyplicate. Seed envelope broadly elliptical with about 30 longitudinal ribs. Polyplicate pollen grains with about 12–14 ribs.

Etymology

From the thin longitudinal ribs on the surface of the seed envelope (Latin tenuis [thin] and costa [rib]).

Stratigraphy

Cretaceous, Lower Cretaceous
Early Cretaceous below the Figueira da Foz Formation; Early Cretaceous (late Aptian–early Albian or potentially older within the Aptian).

Locality

Portugal
Famalicão (lat. 39°42′16″N, long. 08°46′12″W)