Malus atrosanguinea

About

Malus × atrosanguinea, the carmine crabapple, is an artificial hybrid species of flowering plant in the family Rosaceae. Its parents, with considerable uncertainty, are Malus halliana and M. sieboldii. It is a small tree reaching 6 m (20 ft), with carmine flower buds and pink flowers. In the past this hybrid was quite popular on "both sides of the Atlantic", and was available in European nurseries before 1889, when it was sent to the Arnold Arboretum in Boston.

Summary from Wikipedia