In New Zealand, ‘radiata’ and ‘macrocarpa’ are accepted common names for two widely planted non-native conifers: Pinus radiata and Cupressus macrocarpa, known in their native US as ‘Monterey pine’ and ‘Monterey cypress’ respectively.
It’s unusual for the specific epithet of a plant to become the common name. There are plenty of examples of the generic name becoming the common name, from ‘bougainvillea’ to ‘wisteria’. There are even plenty of examples where a former generic name has stuck as the common name after the botanists have renamed the plant to, eg, Pelargonium, Hippeastrum, or Corymbia.
I don’t think I’ve ever heard another example of the specific name working this way, and I only know of one other example. Henry Reed’s famous poem Naming of Parts mentions ‘japonica’, which turns out to be the flowering quince Chaenomeles japonica, and by extension, other species and hybrids of Chaenomeles.
Are there others?