Taxonomic Study of Linaria depauperata and L. supina Complexes 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, floral 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 differences were found in the indumentum distribution and density. Three types of trichomes were identified, 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 conspecific with L. depauperata subsp. hegelmaieri . A key to identify the different taxa is provided.