This tradition is associated with early populations who settled along the Pacific coast between 3000 and 1000 BCE. These communities relied on the natural resources of estuaries, the sea, and lowland areas for their sustenance and survival. As a result of consuming mollusks and crustaceans, discarded shells (such as oysters, mussels, and snails) accumulated over time, forming artificial mounds known as "concheros"—a term that later came to define this early cultural tradition.

Shells and marine snails were initially used for food, but later served as raw materials for the production of ornaments including bracelets, pectorals, earspools, beads, musical instruments, and fishhooks. These crafted items became part of commercial exchange networks between the coastal regions and other parts of western Mexico.

Archaeological studies in Nayarit have helped distinguish between the earliest shell mounds (such as those of the Matanchén Complex) and those from the final stages of occupation during the Postclassic period (including sites like Isla Panales, Litubú, and Punta Mita). These findings support the idea that shell-based materials ("malacological" remains) played a significant role in shaping most of the region’s pre-Hispanic cultural traditions.