One way that archaeologists provide unique conservation datasets is through the establishment of pre-Euroamerican baselines for animal communities that were part of human-environment interactions during the last few millennia. Freshwater mussel remains from archaeological sites offer a rich data source for establishing this type of baseline. We establish a conservation baseline for the late Holocene sandbank pocketbook (Lampsilis satura, Lea 1852) in the upper Trinity River of central and north Texas. These data may 1) lead to greater confidence in existing contemporary data for unoinid biogeography; 2) lead to information on whether or not community composition differs between the late Holocene and today; and/or 3) provide a justification for more intensive contemporary surveys. Such data are relatively easily acquired, inexpensive to generate, and highly informative for environmental management.