Didymo

a freshwater, microscopic diatom (Didymosphenia geminata) typically of cool, nutrient-poor waters of Canada and the northern U.S. and Europe that has become invasive in warmer waters where it forms large, thick brown, yellow, or whitish mats attached to a submerged substrate (such as a rock or plant)

All visitors, especially boaters and fishermen, are being encouraged to wash their gear in an effort to avoid spreading didymo.

Sanskrit equivalent

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