Heavily prevalent in Europe and New Zealand, with a bit in South Africa and couple observations on the west and east coast of America. (https://www.inaturalist.org/taxa/1367002-Crataegus-germanica)
The American variety, Stern's Medlar only has a couple observations in Arkansas (https://www.inaturalist.org/taxa/1368643-Crataegus---canesce...)
Japanese / Chinese Medlar or Loquat are apparently distantly related, yet still have a lot of similarity and edible food (https://www.inaturalist.org/taxa/76949-Eriobotrya-japonica)
If its included in Crataegus (as Crataegus germanica) then it has a bunch of relations like Hawthorn (also edible, https://www.inaturalist.org/taxa/51147-Crataegus-monogyna) and Azaroles (also edible, Haws, https://www.inaturalist.org/taxa/191019-Crataegus-azarolus)
Seems to get heavily mixed in naming with the genus Vangueria in the family Rubiaceae, since they're frequently named Medlar, and have edible fruit, just happen to be mostly from Africa. Really confusing, since they look similar, have similar food, yet apparently different genus, family, and order. Don't cross over until they get all the way up to Clade: Eudicots. Apparently they're attached to bad luck and misfortune, so maybe they got a cursed botanical classification.
Wild-Medlar (Vangueria infausta, Africa) https://www.inaturalist.org/taxa/340324-Vangueria-infausta
Mountain Medlar (Vangueria parvifolia, Africa) https://www.inaturalist.org/taxa/595967-Vangueria-parvifolia
Velvet Wild-Medlar (Vangueria infausta ssp. infausta, Africa) https://www.inaturalist.org/taxa/601546-Vangueria-infausta-i...
Bush Medlar (Vangueria madagascariensis, Africa, S. America) https://www.inaturalist.org/taxa/466936-Vangueria-madagascar...
Natal Medlar (Vangueria lasiantha, Africa) https://www.inaturalist.org/taxa/341606-Vangueria-lasiantha
Waterberg Crowned-Medlar (Vangueria triflora, Africa) https://www.inaturalist.org/taxa/595971-Vangueria-triflora
Forest Crowned-Medlar (Vangueria bowkeri, Africa) https://www.inaturalist.org/taxa/595965-Vangueria-bowkeri