ABSTRACT
Molluscan biodiversity in the Venezuelan Subprovince Extending from the Golfo de Urabá in the west to the western coast of Trinidad in the east, and encompassing the entire northern coast of Colombia and the mainland of Venezuela (Figure 8.1), the Venezuelan Subprovince contains one of the top three richest malacofaunas found in the western Atlantic, with over 1,500 species known from the Colombian coast alone (Daccarett and Bossio, 2011). The species richness of the Venezuelan molluscan assemblages is due primarily to the high productivity and high nutrient levels of the local coastal waters, the result of both heavy river efuent and perpetual wind-driven upwelling systems (Petuch, 1982, 1987, 1988; Vermeij and Petuch, 1986). These productive marine environments also support a large commercial shing industry, primarily for shrimp, and the shrimp boats are often the sole source for collections of deeper water, offshore mollusks. I had the opportunity to work on several Colombian shrimp boats (Vikingos de Colombia Shrimp Company) during the years 1976-1980 and was able to visit and collect in areas that were previously unexplored, primarily along the Goajira Peninsula, off the mouth of the Magdalena River, and in the Golfo de Morrosquillo. Since the shrimpers drag their nets for over three hours at a time, large swaths of sea oor could be sampled, and I collected over 40 new species of macrogastropods from the large piles of marine life that were deposited on deck (Figure 8.2). From these collections, it was apparent that the Venezuelan Subprovince molluscan fauna contains a large component of relict taxa and a very high level of endemicity (Petuch, 1981a).
