AN EARLY EOCENE LEAF FLORA FROM THE RED HOT TRUCK STOP LOCALITY (MERIDIAN, MISSISSIPPI) AND ITS BIOGEOGRAPHIC AND PALEOENVIRONMENTAL SIGNIFICANCE

The Red Hot Truck Stop (RHTS) in Meridian, Mississippi, is a well-dated fossil locality with an unusually rich late Paleocene and early Eocene biota of mammals, fish, snakes, mollusks, foraminifera, calcareous nannoplankton, and plants. The latter include palynomorphs, fruits, and leaves, which are studied here for the first time. We recognize twenty morphotypes (species equivalents) of fossil leaves from the base of the early Eocene Bashi Formation, including representatives of the guava (Myrtaceae), bean (Fabaceae), sumac (Anacardiaceae), laurel (Lauraceae), and palm (Arecaceae) families, as well as the climbing fern Lygodium and a possible specimen of Platycarya (walnut family, Juglandaceae). This flora indicates a subtropical to tropical paleoclimate, in agreement with previous palynological work. Most of the identifiable groups are also present at this time in the Rocky Mountain region, indicating their wide distribution. The Platycarya leaflet, if confirmed, is the first megafossil of this Eocene index taxon found outside of the Rocky Mountains and corroborates the Gulf Coast presence of the genus from pollen data. However, the majority of the morphotypes are not known from the Western Interior U.S., supporting a distinct floral province in accordance with palynological data. The RHTS flora has potential as a reference point for other Wilcox Group floras that are not well dated.