A REVISION OF STYRAX (STYRACACEAE) FOR WESTERN TEXAS, MEXICO, AND MESOAMERICA

Despite a recent taxonomic treatment of Styrax from North America and the Caribbean, the taxonomy of this genus has remained poorly understo od. In an effort to clarify the taxonomy of Styrax from western Texas through Mesoamerica, morphological characteristics of over 2500 specim ens from 29 herbaria were examined. The previous treatment emphasized vegetative characters for circumscription, whereas the present revisio n includes heretofore poorly characterized features of the androecium. This revision comprises 19 species and 24 taxa in the area considered , nearly three times as many species as recognized previously. It incl udes six new species (S. gentryi, S. incarnatus, S. nicaraguensis, S. radians, S. steyermarkii, S. tuxtlensis), two new subspecies (S. plata nifolius subsp. mollis, S. nicaraguensis subsp. ellipsoidalis), three new combinations (S. platanifolius subsp. stellatus, S. platanifolius subsp. texanus, S. platanifolius subsp. youngiae), and two new species names (S. austromexicanus, S. lanceolotus). Two names (S. glabrescens var. pilosus and S. jaliscanus) are lectotypified. Nearly 70% of the species recognized in the revision are narrow endemics. This work has provided the basis for a taxonomic revision of all neotropical Styrax that is currently under way.