Fine-rayed pigtoe, Purple cat’s paw and spectaclecase are just a few of the amusing names given to mussels in Appalachia, one of the continent’s oldest, most biologically diverse mountain ecosystems. What’s troubling is how they, along with dozens of other sensitive freshwater species—including darters and dace—are living in streams where, because of mountaintop-removal mining, water-quality measurements have exceeded toxicity and acidity thresholds thousands of times since 1985.