Not sure if this will be helpful, but a gross search of
World Economic Plants in GRIN for Common name: "Pear" yielded this list of Pyrus.
Pyrus betulifolia Bunge (birch-leaf pear)
Pyrus ×bretschneideri Rehder (Chinese white pear, white pear)
Pyrus calleryana Decne. (Bradford pear, callery pear)
Pyrus communis L. (pear)
Pyrus communis subsp. pyraster (L.) Ehrh. (wild pear)
Pyrus cordata Desv. (Plymouth pear)
Pyrus ×nivalis Jacq. (snow pear)
Pyrus pashia Buch.-Ham. ex D. Don (Himalayan pear)
Pyrus pyrifolia var. culta (Makino) Nakai (Asian pear, Chinese pear, Chinese sand pear, Japanese pear, nashi pear, Oriental pear, sand pear)
Pyrus salicifolia Pall. (willow-leaf pear)
Pyrus ×sinkiangensis T. T. Yu (Xinjiang pear)
Pyrus spinosa Forssk. (almond-leaf pear)
Pyrus ussuriensis Maxim. (Harbin pear, Manchurian pear, Ussuri pear, Ussurian pear)
