Takhtajania perrieri - the only extant representative of the family Winteraceae.

It is the largest extant representative of the family Megapodiidae and is one of three species to inhabit Australia.

Sometimes called a "living fossil", it is the only extant representative of the family Mitsukurinidae, a lineage some 125 million years old.

Trichoplax adhaerens is the only extant representative of phylum Placozoa, which is a basal group of multicellular animals (metazoa).

The koala (Phascolarctos cinereus) is an arboreal herbivorous marsupial native to Australia, and the only extant representative of the family Phascolarctidae.

The faunal inventory consists primarily of European ice age faunas and/or their extant representatives.

On this basis, the Hula painted frog has been labeled a living fossil, the only extant representative of an ancient genetic split.

The group is the sole extant representative of the Notostigmomorpha, defined by having a single spiracle opening at the posterior of each dorsal plate.

The only extant representative of this family is the Japanese umbrella pine, Sciadopitys verticillata.

The smooth-coated otter (Lutrogale perspicillata) is a species of otter, the only extant representative of the genus Lutrogale.