The <i>Lycopsid sigillaria brardii</i> Brongniart From The Late Pennsylvanian Tinajas Member, Atrasado Formation, Socorro County, New Mexico

Abstract

Excellent specimens of Sigillaria brardii were found in place on the surface of shale in Upper Pennsylvanian (Missourian) strata of Socorro County, New Mexico. Poor quality specimens have been reported from the Upper Pennsylvanian of New Mexico earlier, on at least two occasions. The current specimens, preserved in ironstone, reveal fine details of the stem surface. Given the large plant-fossil collections that have been made from the Pennsylvanian strata of Socorro County, the rarity of this plant is unusual and may reflect a scarcity of wetland habitat conditions in the region. Sigillaria brardii is the only arboreous lycopsid reported from Upper Pennsylvanian strata in equatorial latitudes of Euramerican Pangea, from the Appalachian coal basin to areas lacking coal in the western parts of the paleocontinent following the disappearance of other kinds of lycopsid trees at the DesmoinesianMissourian stage boundary.