Nucleariid genera

Nuclearia is a genus of nucleariid amoebae with filose pseudopodia and discoid mitochondrial cristae.

Fonticula is a genus of cellular slime mold which forms a fruiting body in a volcano shape. As long ago as 1979 it has been known to not have a close relationship with either the Dictyosteliida or the Acrasidae, the two well-established groups of cellular slime molds. In 1979, Fonticula was made a new genus of its own due to the unique characteristics of its fruiting body, with only one species: Fonticula alba.

Rabdiophrys is a genus of eukaryotes of unclear placement. As molecular data is unavailable (as of 2019), it has been placed by morphology in Nucleariida or Rhizaria (Chao and Cavalier-Smith).

Pompholyxophrys is a genus of Opisthokonta appearing as a scale-bearing filose amoeba.

Parvularia atlantis is a filopodiated amoeba which was isolated from a lake in Atlanta and deposited in the American Type Culture Collection (ATCC) under the name Nuclearia sp. ATCC 50694 on 1997 by TK Sawyer. It was classified under the genus Nuclearia and morphologically resembles to Nuclearia species, although it is smaller (the diameter of the cell body measures approximately 4 μm compared to Nuclearia species, which range between 9-60 μm). Later it was determined that it phylogenetically belongs to a new nucleariid lineage, the genus Parvularia, distantly related to Nuclearia an

Pinaciophora is an amoeboid genus of uncertain affinity, previously classified as Rhizaria or the now-discredited Heliozoa. It has also been placed in Nucleariida, which remains a possibility based on morphology. There is no molecular data available for a definite placement as of 2019.