Concise hierarchy

(Kingdom) Animalia - (Phylum) Chordata - (Class) Reptilia - (Order) Ornithischia

Phylogeny

Node-based clade

Ref: P.C. Sereno, 1998: table 4 (p. 61).

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

†Ankylosaurus (Genus) Brown, 1908		Ref: P.C. Sereno, 1998: table 4 (p. 61).
†Triceratops (Genus) Marsh, 1889		Ref: P.C. Sereno, 1998: table 4 (p. 61).

Current position

†Ornithischia (Order) Seeley, 1887

Ref: M.J. Benton, 2005: box 8.5.

Alternative positions

†Ornithischia (Clade) Seeley 1887 [Padian & May 1993]

Ref: P.C. Sereno, 1998: table 4 (p. 61).

Historical positions

†Ornithischia (Order) Seeley, 1887	Ref: M.J. Benton, 2005: box 8.5.
†Ornithischia (Clade) Seeley 1887 [Padian & May 1993]	Ref: P.C. Sereno, 1998: 66, table 4 (p. 61), fig. 4.
†Ornithischia (Clade) Seeley 1887 [Padian & May 1993]	Ref: M.J. Benton, 1990: fig. 1.5.

Number of Subtaxa

2024	Available in Systema Naturae 2000	†17f;157g;66s;5
1989-present	Systema Naturae 2000	[; †18f;176g]