Raunsgaardispermum lusitanicum gen. et sp. nov., a new seed with in situ pollen from the Early Cretaceous (probably Berriasian) of Portugal: Further support for the Bennettitales-Erdtmanithecales-Gnetales link

Abstract

A new genus and species, Raunsgaardispermum lusitanicum, is described from the Bombarral formation, Early Cretaceous (probably Berriasian) of Portugal. The new taxon is based on small well-preserved, lignitised seeds, about 1.2 - 2.1 mm long and 0.9 - 1.26 mm wide, ovoid to broadly elliptic in outline with a distinct pointed micropylar region. The seed wall is composed by a thin membranous integument extended apically into a long tubular micropyle. The integument is enclosed almost completely by an outer envelope except for a small circular opening for micropylar region. The outer envelope is bivalved and sclerenchymatous, ornamented by narrow longitudinal ridges. Papillae are present apically on the inner surface of the seed envelope adjacent to the micropylar tube. Monocolpate, tectate-psilate-punctate pollen grains, about 26 - 29 μm long and 14 - 16 μm wide, were observed in situ in the micropyle of one seed and on the outer surface of several others. The seeds show an interesting character combination of distinct ephedroid seed characters coupled with pollen characters of Bennettitales and Erdtmanithecales and add further evidence to the link between Bennettitales, Erdtmanithecales and Gnetales. © 2008 Collegium Palynologicum Scandinavicum.