Taxonomic study of Linaria depauperata and Linaria supina groups in Eastern Spain.
Morphological characteristics were studied in two groups of closely related taxa of section Supinae, Linaria
depauperata and L. supina, from eastern Spain. Vegetative, ¯oral and seed characteristics were of little use in
distinguishing between these taxa as the ranges for all the taxa studied overlapped. Flower colour could be used as a
diagnostic character for some but not all of these taxa. Seed coat characters were of high taxonomic value, both
when trying to distinguish among these two groups, and the taxa included within them, and also when establishing
relationships among the taxa studied. Some dierences were found in the indumentum distribution and density.
Three types of trichomes were identi®ed, two of them eglandular and common to all taxa. The third type of trichome
was a simple gland, that varied in the number of cells in the stalk and gland. Trichome length and wall width of stalk
cells allowed several groups of taxa to be distinguished. Similarity relationships among the samples studied are
shown in a UPGMA phenogram. According to these results, two new species, L. cardonica and L. sulphurea, are
described. L. arabiniana is conspeci®c with L. depauperata subsp. hegelmaieri. A key to identify the dierent taxa is