Concise hierarchy

(Kingdom) Plantae - (Phylum) Tracheophyta - (Class) Archaeopteridopsida

Subsequent positions

Lignophyta (Clade) Crane & Kenrick 1997, nom. cl. inval.

Ref: P.R. Crane & P. Kenrick, 1997: tables 6 (p. 97), 7 (p. 98). [implicit]

Current position

†Archaeopteridopsida (Class) Takht. (1978)

Ref: A.B. Doweld, 2001: XIII.

Alternative positions

Lignophyta (Clade) Crane & Kenrick 1997, nom. cl. inval.	Ref: P.R. Crane & P. Kenrick, 1997: table 7 (p. 98). [inferred rank]
Lignophytia (Supercohort)	Ref: P. Kenrick & P.R. Crane, 1997a: table 7.1 (p. 229).
†Progymnospermopsida (Class) Beck (1960)	Ref: Новіков, А. & Барабаш-Красни, Б. / Novikoff, A. & Barabasz-Krasny, B., 2015: 54.
†progymnosperms ([unranked])	Ref: P.D. Cantino et al., 2007: E17.

Historical positions

†Progymnospermopsida (Class) Beck (1960)	Ref: A. Novikoff & B. Barabasz-Krasny, 2015: 54.
†Progymnospermophyta (Phylum) Lang (1925)	Ref: T.N. Taylor et al., 2009: App. 1 (p. 1028).
†progymnosperms ([unranked])	Ref: P.D. Cantino et al., 2007: E17 ("e.g.").
†Archaeopteridopsida (Class) Takht. (1978)	Ref: A.B. Doweld, 2001: XIII.
Lignophytia (Supercohort)	Ref: P. Kenrick & P.R. Crane, 1997a: table 7.1 (p. 229).
Lignophyta (Clade) Crane & Kenrick 1997, nom. cl. inval.	Ref: P.R. Crane & P. Kenrick, 1997: table 7 (p. 98), fig. 1.
†Progymnospermopsida (Class) Beck (1960)	Ref: C.J. Cleal & B.A. Thomas, 1995: 13.

Number of Subtaxa

2024	Available in Systema Naturae 2000	†1f;9g
1989-present	Systema Naturae 2000: 1 Apr 2023	[; †1f;9g]
2015	A. Novikoff & B. Barabasz-Krasny: 54	[; †1f;7g]
2001	A.B. Doweld: XIII	[; †1f]
1995	C.J. Cleal & B.A. Thomas: 13	[; †1f]