Stanwoodia, a new probable early gymnosperm from the Dinantian of East Kirkton, Scotland

Abstract

A new taxon of probable early gymnosperms is described from permineralised specimens showing excellent preservation of the tissues, from the late Lower Carboniferous (Dinantian), Brigantian, deposits of the Midland Valley of Scotland. Stanwoodia gen. nov., represented by the single species S. kirktonensis sp. nov., shows the combination of a primitive protostelic organisation with a dense secondary wood. It closely compares to the enigmatic genus Bilignea which was formerly referred with some reservations to the Cordaitales. Another interest of the new plant concerns the excellent preservation of the phloem with at least three different types of constituent cells including fibres. Stanwoodia also exhibits the oldest well-documented evidence of a sequent periderm or rhytidome in fossil plants.