Which supergroup of eukaryotes includes both animals and fungi?

The supergroup of eukaryotes that includes both animals and fungi is Opisthokonta.

Opisthokonta is a broad evolutionary clade within Eukaryota. Its two major branches are Holomycota, containing fungi and their close relatives, and Holozoa, containing animals and their close relatives. The group also includes several unicellular lineages, including choanoflagellates and filastereans.

The name refers to a posterior flagellum. In many opisthokonts, motile cells propel themselves with a single flagellum positioned at the rear. Animal sperm show this feature, as do the swimming spores of chytrid fungi, although flagella have been lost in most fungi.

The relationship is easy to miss because animals and fungi look radically different and were once often placed far apart in classification schemes. Molecular and phylogenomic evidence instead shows that they share a relatively recent common ancestry. Amoebozoa is a neighboring major eukaryotic group, while Archaeplastida includes plants and Excavata is an older, informal grouping of several protist lineages.