Paurodendron stellatum: A new Permian permineralized herbaceous lycopsid from the Prince Charles Mountains, Antarctica
Abstract
Diminutive, silica-permineralized lycopsid axes, from a Guadalupian (Middle Permian) silicified peat in the Bainmedart Coal Measures of East Antarctica are described and assigned to Paurodendron stellatum sp. nov. Axes consist only of primary-growth tissues with a vascular system characterized by an exarch actinostele with 6-20 protoxylem points. Stems have a relatively narrow cortex of thin-walled cells that are commonly degraded, but the root cortex typically contains more robust, thick-walled cells. The stems bear helically inserted, elliptical-rhombic, ligulate microphylls. Roots possess an eccentrically positioned monarch vascular strand. Paurodendron stellatum is one of a very small number of anatomically preserved lycopsid axes described from the Gondwanan Permian and represents the first post-Carboniferous record of this genus. Based on dispersed vegetative remains, megaspores and microspores, herbaceous lycopsids, such as P. stellatum, appear to have been important understorey components of both low- and high-latitude mire forests of the late Palaeozoic.
- Publication:
-
Review of Palaeobotany and Palynology
- Pub Date:
- September 2015
- DOI:
- 10.1016/j.revpalbo.2015.04.004
- Bibcode:
- 2015RPaPa.220....1M
- Keywords:
-
- Heterosporous lycopsida;
- Isoëtales;
- Bainmedart coal measures;
- Lycopsid anatomy;
- Megaspore;
- Gondwana