Allium cristophii  

Allium cristophii Trautv. (Turkey, Iran and Turkmenistan) – A very rare and probably ephemeral escape from cultivation or, more likely, a throw-out. Observed since 2011 in a few, widely scattered localities, e.g. in Sint-Maria-Horebeke, Kessel-Lo, Olmen and Lanaken.
Although much grown these days, Allium cristophii is surprisingly rare as an escape from cultivation.
Of the spectacular onions currently widely offered for sale in the horticultural trade, Allium cristophii is easily recognized by its leaves with hairy margins and its stamens that are much shorter than the perianth.
The correct spelling of the specific epithet is "cristophii" as recommended by the Committee for Spermatophyta (Brummitt 2001).

Selected literature:

Brummitt R.K. (2001) Report of the Committee for Spermatophyta: 48. Taxon 50(2): 559-568.

Fritsch R.M. (2016) A Preliminary Review of Allium subg. Melanocrommyum in Central Asia. Leibniz-Institut für Pflanzengenetik und Kulturpflanzenforschung Gatersleben (IPK): 288 pp. [available online at: https://www.researchgate.net/publication/312948014_A_Preliminary_Review_...