AN HISTORICAL OVERVIEW OF PALEONTOLOGICAL RESEARCH OF THE EOCENE REPUBLIC LOCALITY, NORTHEASTERN WASHINGTON STATE, USA

The late Early to early Middle Eocene Republic flora of northeastern Washington State has been known for over a century. Umpleby (1910) first noted that plant and fish fossils occurred in tuffs (dated Miocene on the basis of fish) in association with several area gold mines. Berry (1929) briefly described specimens from Republic as part of the Miocene Latah Formation, and Brown (1935, 1937, 1939, and 1940) documented further occurrences of selected taxa. Nothing more was published until 1960 when Wolfe and Barghoorn suggested an Eocene age for the Republic flora and compared it to floras at Princeton, BC and Florissant. Outcrops scouted by Wehr and Johnson in 1977 demonstrated that Republic was a more extensive and diverse flora than previously thought, and Wehr collected extensively at Republic and the Toroda Creek area. Wolfe and Wehr (1987) published a USGS monograph on Republic, with detailed taxonomic studies on Macginitiea (Manchester 1986), Abies milleri (Schorn and Wehr 1986), and Betula leopoldeae (Stockey and Crane 1987). In 1984, Wehr and Republic city councilman Bert Chadwick developed the idea of Stonerose Interpretive Center as a means for managing fossil collecting at the site. Stonerose Interpretive Center was established in 1988, allowing for monitored collections by the general public. This intensive sampling has provided a basis for detailed interpretation of the origin and evolution of biotic diversity. Washington Geology published papers on the diversity of the Republic flora, and in 1996 devoted an entire volume to the Republic centennial, drawing together regional geology, mining history, paleoecology, and plant, fish and insect diversity. The broader significance of Republic “upland” flora to paleoclimate and paleoelevation was addressed by Wolfe, and subsequent studies used the flora as a model to compare with contemporaneous floras (Wilf, Johnson, Royer). Insect damage patterns in leaves denoted plant-animal interactions (Labandeira). Since the 1990s systematic work on insects has concentrated on Neuroptera, Hymenoptera, and Mecoptera (Archibald), and plant studies on Betulaceae, Trochodendraceae, Hamamelidaceae and Rosaceae. Republic is a critical touchstone for understanding the contrast of warmer Eocene floras to those characterized by more temperate elements.