Atlas of Selected Kinney Quarry Plant Fossils, Late Pennsylvanian, Central New Mexico

Abstract

During the Late Pennsylvanian, seasonality and rainfall increased in western Pangea, which led to the expansion of "mixed" floras composed of a combination of wetland and drought-tolerant plants. One notable example is the flora of the Kinney Brick Quarry, a Missourian Lagerstätte southeast of Albuquerque, New Mexico, USA, deposited in an embayment by a prograding delta in a seasonal, subhumid climate. A controlled excavation of the quarry and bed-by-bed quantitative analyses of the floral composition revealed a transition from dominance by wetland plants to drought-tolerant plants. In this study, we provide a visual reference of important plant taxa from each of the six productive beds in the controlled excavation. Pteridosperms, conifers, and filicalean ferns are present in all six beds; lycopsids, marattialean ferns, and cordaitaleans range through Beds 2-5; sphenopsids, dicranophylls, and noeggerathialeans span Beds 2-6; and Taeniopteris species are present only in Bed 4. The stratigraphic ranges of plants at Kinney suggest that, although there were changes in species dominance patterns, the overall species pool stayed consistent throughout deposition of the strata. We also hypothesize the habitat preferences of fossil plant taxa from Kinney based on morphological adaptations, modeled physiological requirements, and depositional environment interpretations of other localities where the same plant species occur. These interpretations suggest a landscape with varied microhabitats accommodating plants with an array of moisture tolerance levels, with wetland plants colonizing the shoreline, along rivers, and other moist substrates, and meso- and xeromorphic plants occupying areas experiencing seasonal drought.