Lignierispermum E.M.Friis, K.R.Pedersen et P.R.Crane
Plant Fossil Names Registry Number: PFN002856
Act LSID: urn:lsid:plantfossilnames.org:act:2856
Reference: Friis, E. M., Pedersen, K. R. & Crane, P. R. (2009): Early Cretaceous mesofossils from Portugal and eastern North America related to the Bennettitales-Erdtmanithecales-Gnetales group. – American Journal of Botany 96(1): 252–283.
Page of description: 264
Lignierispermum maroneae E.M.Friis, K.R.Pedersen et P.R.Crane
Seeds small, obovoid, micropylar region pointed; four-angled, slightly fl attened, bisymmetrical (with two planes of symmetry) in cross section. Integument thin, micropylar tube long, narrow. Integument enclosed by a seed envelope, except for the micropylar opening, and attached to the envelope only at the base. Nucellus thin, enclosed by the integument; nucellus free distally, otherwise fused to the integument. Micropyle open at the apex. Below, micropylar closure distinct, multicellular, formed from several cell layers fi lling the lower half of micropylar tube. Inner surface of seed envelope smooth, nonpapillate; outer surface smooth. Seed envelope sclerenchymatic comprising two distinct layers. Inner layer composed of transversely aligned fiber cells; at the apical corners of the seed, the fi ber cells radiate toward the outside to form four, narrow, wing-like, apically pronounced crests. The outer layer is composed of radially extended cells that increase in size toward the apex and shorter, thin-walled cells covered by a distinct epidermis of equiaxial cells. Four distinct longitudinal bundles extend in the outer layer of the seed envelope from the seed base to apex.
In honor of the French palaeobotanist Octave Lignier for his contribution to the understanding of reproductive structures of Bennettitales.