Input (grade 13): Within the genus Prunus, it is classified with the peach in the subgenus Amygdalus, distinguished from the other subgenera by the corrugated shell (endocarp) surrounding the seed.
Output (grade 5): Within the genus Prunus, it is classified in the subgenus Amygdalus. Amygdalus is told apart from other subgenera by the wavy seed shell.