Foley, M. J. Y., Hedge, I. C. & Möller, M.: The enigmatic Salvia tingitana (Lamiaceae): a case study in history, taxonomy and cytology. — Willdenowia 38: 41–59. — ISSN 0511-9618; © 2008 BGBM Berlin-Dahlem. doi:10.3372/wi.38.38102 (available via  http://dx.doi.org/)

Salvia tingitana has been in cultivation since at least the end of the seventeenth century, but its provenance has for long been uncertain and its taxonomic interpretation confused. With new evidence that has come to light, a more complete botanical and horticultural history of the plant is presented. It covers a period of almost 400 years. Uncertainties, however, still remain about its original introduction; today the only certain known wild locality is in Saudi Arabia. A chronological history of its treatment and misinterpretations by various authors over the centuries is given. Based on current knowledge, there is an up-dated description and discussion of its affinities. An investigation into its cytology gave a chromosome number of 2n = 42, very unusual in the genus, the significance of which is discussed. Examination of the mucilage produced by nutlets on wetting was also revealing per se and showed differences from mucilage produced by its putative allies.