Drawing of Salinella by Johannes Frenzel.
Salinella salve is a cryptid microorganism reported in 1892 from the salt plains of Argentina, the sole representative of the contested phylum Monoblastozoa. It was discovered and cultivated by Johannes Frenzel, and has not been found again since.[1] "They are characterised by their distinct anterior/posterior parts and being densely ciliated, especially around the "mouth" and "anus". They have only one layer of cells. They reproduce asexually by transverse fission of their bodies".
German zoologist Michael Schrödl led a search for Salinella in Argentina, but found the area of salt plains where Frenzel discovered it replaced by farmland.[1]