Fitting into about a tenth of a millimeter, Vorticella is a weird little spring-loaded aquatic vacuum cleaner, here anchored to some fragmentary algae. That blur around its mouth as it reaches out is the rapid rotation of cilia around the mouth to create suction, and that moment of snapping back is so fast that it happens between two frames of the video--less than 1/30th of a second. July 19th, 2023.
