The first description as
Escobesseya duncanii by J. Pinckney Hester was published in 1945. The specific epithet duncanii honors the American Frank Duncan, who owned the
mining field where the species was discovered. Franz Buxbaum placed the species in the genus
Escobaria in 1960. David Aquino & Daniel Sánchez moved the species to
Pelecyphora based on
phylogenetic studies in 2022. Further
nomenclature synonyms are
Escobaria duncanii (Hester) Backeb. (1961),
Coryphantha duncanii (Hester) L.D.Benson (1969),
Mammillaria duncanii (Hester) D.Weniger (1970),
Escobaria dasyacantha var.
duncanii (Hester) N.P.Taylor (1983) and
Neobesseya duncanii (Hester) Lodé (2013). == References ==