Rothwellia E.M.Friis, P.R.Crane et K.R.Pedersen

Plant Fossil Names Registry Number: PFN000211

Act LSID: urn:lsid:plantfossilnames.org:act:211

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

Rank: genus

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: 651

Type

Original diagnosis/description

Seeds small and orthotropous. Integument free from the seed envelope for its full length except at the base, where it is broadly attached. Integument extended apically into a long micropylar tube. Micropylar tube formed by an inner and an outer epidermis. Micropylar canal open apically, closed farther down by the cells of the inner epidermis that expand radially toward the center of the canal. Seed envelope ellipsoidal, four angled to almost circular in transverse section. Surface of seed faintly rugulate-foveolate. Micropylar region of seed envelope only slightly extended. Inner surface of the seed envelope in the micropylar region smooth, lacking papillae. Outer epidermis of seed envelope of polygonal, longitudinally aligned cells with a thin cuticle. Sclerenchyma zone of seed envelope with an inner layer of narrow, transversely elongate cells and an outer layer of shorter, radially extended cells with unevenly thickened walls. Zone of parenchyma cells present between the sclerenchyma layer and the outer epidermis. Embryo with two cotyledons.

Etymology

In honor of Gar Rothwell for his many contributions to paleobotany.