Lamium bifidum subsp. bifidum

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 : 148

(a) Subsp. bifidum :

Lower leaves incised, cordate to almost truncate at base. Calyx-teeth distinctly shorter than tube. Corolla 20-25 mm, white. Mediterranean region from Corse and Sardegna eastwards; C. Portugal.