The fruit is a dark red pome 6–10 mm (0.2–0.4 in) diameter, slightly broader than long, containing two or three nutlets.

[8] It is distinguished from the closely related common hawthorn, C. monogyna, in the leaves being only shallowly lobed, with forward-pointing lobes, without hair tufts in the vein axils, and in the flowers having more than one style.

In 1775, Jacquin formally separated the common hawthorn, naming it C. monogyna,[9] and in 1946, Dandy showed that Linnaeus had actually observed a different plant, C. oxyacantha.

By this time, though, confusion over the true identity of C. oxyacantha was so great that Byatt proposed[10] that the name should be formally rejected as ambiguous, and this proposal was accepted by the International Botanical Congress,[11] although the name continues to be used informally.

[12] 'Paul's Scarlet'[13] (double red flowers), 'Punicea'[14] (pink and white) and 'Rosea Flore Pleno'[15] (double pink flowers) have gained the Royal Horticultural Society's Award of Garden Merit.