Many bivalves and gastropods from marine reducing environments such as deep ocean hydrothermal vents and seeps host chemosynthetic bacteria in a nutritional symbiosis. Despite their functional similarities. the distribution of chemosymbiosis in these two mollusk classes is surprisingly uneven: the number of bivalve species known to host chemosynthetic symbionts is more than twenty tim... https://www.markbroyard.com/flash-grab-hobbit-door-on-sale-limited-grab/