Micromollusks are tiny shelled invertebrates ranging in size from 5mm down to the smallest member, Ammonicera minortalis, at 0.4mm. For the phylum of Mollusca, for example, 70,000 species have been documented so far and another 150,000 are estimated to exist. But due to their tiny size, many submillimeter species have evaded detection for so long. Researchers have to sift through bags of sand and spend hours sorting under the microscope to find a specimen or even a new species. Since micromollusks are not visible to the naked eye, collecting a living specimen is quite unlikely. Many mysteries about them still await discovery.
Depicted above: Noctiluce scintillans (glowing dinoflagellates), Rissoella Morrocoyensis (spotted snail)
Length of Rissoella Morrocoyensis: ca 1mm