Mentha microphylla, C. Koch

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1972, Flora Europaea. Volume 3. Diapensiacea to Myoporaceae, Cambridge: Cambridge University Press : 186

13. M. microphylla C. Koch , Linnaea 21: 648 (1849)

(AT. sieberi auct.,? an C. Koch).

Like 12 but with leaves 10-45x 5-20(-25) mm, broadly ovate to lanceolate, widest below the middle, strongly rugose, tomentose and grey or grey-green on both surfaces, serrate with usually few salient teeth, undulate, the hairs on the lower surface both simple and branched with the basal cell 44-63 p m in diameter; verticillasters usually remote, forming a little-branched spike 60-120 x 5-10 mm; calyx 1-2 mm; fertile anthers 0-30-0-44 mm; nutlets 0-6-0-83 mm. 2«=48. S. Italy, Sicilia; Balkan peninsula and Aegean region. Al Bu Cr Gr It Ju?Sa Si Tu.

Apparently an allotetraploid originally derived from 11 and 12.