Nomenclatural notes on two names of elms published by P. Miller and R.A. Salisbury: Ulmus sativa and U. procera (Ulmaceae)

Typification of the elm species names Ulmus procera Salisb. and U. sativa Mill. is discussed. Both these names are lectotypified on illustrations (which seem to be the only extant original material for each name) published in Gerard’s The Herball, or, Generall historie of plantes, i.e., respectively, “Ulmus vulgatissima folio lato scabro” and “Ulmus minor, folio angusto, scabro”. The available molecular and morphological data indicate that the plants placed in U. procera are related to U. minor s. l., a Eurasian variable species that includes two currently recognized infraspecific taxa, i.e. subsp. minor and subsp. canescens. Supported by the present nomenclatural study, a coherent taxonomic choice is to consider U. procera as a subspecies of U. minor (not as a heterotypic synonym of U. minor subsp. minor, as recognized by various authors). Based on morphological observations, U. minor subsp. procera can be distinguished from the other two subspecies (subsp. minor and subsp. canescens) by the lower length/width ratio of the leaf blades (1.1–1.6 vs. 1.7–2.5 times longer than wide). Concerning Miller’s U. sativa, its leaves features match those of U. minor subsp. minor, and the two names are here synonymized.