Concise hierarchy

(Kingdom) Animalia - (Phylum) Chordata - (Class) Mammalia

Phylogeny

Crown clade		Ref: M.A. O'Leary et al., 2004: 491 ("crown clade").
Reference phylogeny [PhyloCode]		Ref: M.A. O'Leary et al., 2004: fig. 28.2. [inferred]

First representative

†Leptacodon proserpinae Van Valen, 1978		Ref: M.A. O'Leary et al., 2013: table S2 (p. 85).
†Protungulatum donnae Sloan & Van Valen, 1965		Ref: M.A. O'Leary et al., 2013: table S2 (p. 85).
†Purgatorius coracis Fox & Scott, 2011		Ref: M.A. O'Leary et al., 2013: table S2 (p. 85).

Defined by the most recent common ancestor (and all its descendants) of

Bos taurus Linnaeus, 1758		Ref: M.A. O'Leary et al., 2004: 491.
Dasypus novemcinctus Linnaeus, 1758		Ref: M.A. O'Leary et al., 2004: 491.
Elephas maximus Linnaeus, 1758		Ref: M.A. O'Leary et al., 2004: 491.

Included, by definition, in node-based clade

Theria (Clade) Parker & Haswell 1897 [McKenna 1975]

Ref: T. Rowe, 1988: 247, 251 ("placentals").

Current position

Eutheria (Infraclass) Gill, 1872

Ref: Z. Kielan-Jaworowska et al., 2004 (alt.): table 1.1 (p. 15).

Alternative positions

Eutheria (Clade) Gill 1872 [O'Leary, Allard, Novacek, Meng & Gatesy 2004]	Ref: M.A. O'Leary et al., 2004: fig. 28.2.
Theria (Clade) Parker & Haswell 1897 [McKenna 1975]	Ref: T. Rowe, 1988: fig. 3.

Historical positions

Theria (Clade) Parker & Haswell 1897 [McKenna 1975]	Ref: K. de Queiroz et al., 2020: x.
Eutheria (Infraclass) Gill, 1872	Ref: S. Bi et al., 2018: fig. 4.
Eutheria (Clade) Gill 1872 [O'Leary, Allard, Novacek, Meng & Gatesy 2004]	Ref: M.A. O'Leary et al., 2013: table S4 (pp. 100, 101).
Eutheria (Clade) Gill 1872 [O'Leary, Allard, Novacek, Meng & Gatesy 2004]	Ref: M.A. O'Leary et al., 2004: fig. 28.2.
Eutheria (Infraclass) Gill, 1872	Ref: Z. Kielan-Jaworowska et al., 2004 (alt.): table 1.1 (p. 15).
Theria (Clade) Parker & Haswell 1897 [McKenna 1975]	Ref: T. Rowe, 1988: figs. 3, 4.