Evidence for gondwanan origins for sassafras (lauraceae)? : late cretaceous fossil wood of antarctica

Abstract

Sassafrasoxylon gottwaldii sp. nov. is a new taxon for fossil wood with a suite of features diagnostic of Sassafras Nees & Eberm. of the Lauraceae. The fossil wood described is from Late Cretaceous (Santonian- Maastrichtian) sediments of the northern Antarctica Peninsula region. This new species of Sassafrasoxylon Brezinová et Süss resembles the species of extant Sassafras in being distinctly ring-porous, having vessel elements with simple perforation plates and very occasional scalariform plates with relatively few bars in the narrowest latewood vessels, alternate intervascular pitting, marginal (initial) parenchyma bands and paratracheal vasicentric parenchyma in the latewood, multiseriate rays and oil and /or mucilage cells. The fossils were found as isolated pieces of wood and therefore it is not certain whether the parent plant was Sassafras- like in all characters. Consequently the fossils have been placed in an organ genus rather than in extant Sassafras. This is the oldest record of an organ with features closest to extant Sassafras and may suggest that Sassafras first appeared in Gondwana and later radiated into the Northern Hemisphere. The distribution of extant Sassafras in North America and East Asia may represent a relict of a geographically more widespread taxon in the past.