+ Pyrocrataegus is an artificial hybrid genus in the family Rosaceae involving the genera Crataegus and Pyrus+ Pyrocrataegus Rehder. (n.d.). Plants of the World Online. Retrieved January 14, 2026, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:77220983-1 with an unclear taxonomic status. It is mostly believed to be a graft-chimaera, but could possibly be a sexual hybrid instead.
Description The foliage, flowers, and fruits resemble those of the genus Pyrus.Chevalier, A. (1952). Réflexions sur l'avenir de la culture des arbres fruitiers du groupe des Pomacées et sur les possibilités de leur amélioration. Journal d'agriculture traditionnelle et de botanique appliquée, 32(361), 533-547. The inflorescence is corymbose. The small, red, pyriform fruit is 1.5–3 cm long.Rehder, A. (1927). Manual of cultivated trees and shrubs hardy in North America, exclusive of the subtropical and warmer temperate regions. p. 376. Macmillan Company.
Taxonomy It was first described as + Pirocrataegus by Lucien Louis Daniel in 1915,+ Pirocrataegus L.L.Daniel. (n.d.). Plants of the World Online. Retrieved January 14, 2026, from https://powo.science.kew.org/taxon/urn:lsid:ipni.org:names:77220947-1 but this description may be a Nomen nudum. It was described a second time as + Pyrocrataegus by Alfred Rehder in 1927.Pyrocrataegus Rehder. (n.d.). International Plant Names Index. Retrieved January 14, 2026, from https://www.ipni.org/n/77220983-1 The correct genus authority is unclear. Some sources credit Lucien Louis Daniel, while others credit Alfred Rehder as the taxon author.×Pyrocrataegus Rehder in GBIF Secretariat (2023). GBIF Backbone Taxonomy. Checklist dataset https://doi.org/10.15468/39omei accessed via GBIF.org on 2026-01-14. It is an artificial hybrid genus involving Crataegus and Pyrus. Some sources treat it as an "unplaced name".Pyrocrataegus Rehder. (n.d.-b). WFO Plant List. Retrieved January 14, 2026, from https://wfoplantlist.org/taxon/wfo-4100001186-2025-12 Its status is somewhat uncertain: Some treat it as a genus of graft-chimaera,McNeill, J., Shaw, J. M., & Wiersema, J. H. (2016). Proposal to preclude homonymy of generic names with names of intergeneric graft-hybrids (chimaeras). Taxon, 65(5). some as a nothogenus, and some sources simply list it as a genus. This intergeneric hybrid between Pyrus and Crataegus is yet to be confirmed by modern taxonomical methods.Vidaković, A., Šatović, Z., Liber, Z., Jurica, M., & Poljak, I. (2025). Leaf morphological variability of Pyrus spinosa and Crataegus monogyna and their potential hybridization. Acta Botanica Croatica, 84(2), 0-0.
Its only species Pyrocrataegus willei Pyrocrataegus L.L. Daniel. (n.d.). Interim Register of Marine and Nonmarine Genera (IRMNG). Retrieved January 14, 2026, from https://www.irmng.org/aphia.php?p=taxdetails&id=1043572 was described by Lucien Louis Daniel in 1915.Rehder, Alfred. (1949). Bibliography of cultivated trees and shrubs hardy in the cooler temperate regions of the Northern Hemisphere (p. 252). Arnold Arboretum of Harvard Univ. https://www.biodiversitylibrary.org/page/39585045 Etymology The generic name Pyrocrataegus combines the genera Pyrus and Crataegus.GENAUST. (2013). Etymologisches Wörterbuch der botanischen Pflanzennamen. p. 311. Germany: Birkhäuser Basel.
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