Syncaris pacifica is an endangered species of freshwater shrimp in the family Atyidae that occurs only in a limited range within the northern San Francisco Bay Area, California, USA. Specifically, this species occurs only in 17 stream segments within Sonoma, Napa and Marin Counties. This species is often translucent to transparent, with both sexes capable of considerable coloration altering, as a sophisticated form of camouflage. This decapod is commonly known as California freshwater shrimp, and is the only decapod shrimp in California that occurs in non-saline waters.