Mulinia modesta is a species of clam belonging to the family Mactridae.

The Colorado River Delta is the region where the Colorado River flows into the Gulf of California in eastern Mexicali Municipality in the north of the state of Baja California in northwesternmost Mexico. The delta is part of a larger geologic region called the Salton Trough. Historically, the interaction of the river's flow and the ocean's tide created a dynamic environment, supporting freshwater, brackish, and saltwater species. Within the delta region, the river split into multiple braided channels and formed a complex estuary and terrestrial ecosystems. The use of water upstream and the accompanying reduction of freshwater flow has resulted in the loss of most of the wetlands of the area, as well as drastic changes to the aquatic ecosystems. However, a scheme is currently in place which aims to rejuvenate the wetlands by releasing a pulse of water down the river delta.