[4][5] The 2–6 yellow pedicellate flowers are borne at the end of a scape up to 33 cm long.

[4] The floral tube is greenish yellow, 5–7.5 cm long, bearing at the end the tepals, which are linear to narrowly lanceolate, 6–7.5 cm long, with green tips.

[4][6][5] Endemic to Peru, Ismene amancaes inhabits coastal hills up to 1500 m of elevation, especially near the city of Lima, as part of the lomas ecosystem.

[10] Remains of I. amancaes have been found in archaeological sites near the city of Lima.

[12] In a place among the hills surrounding Lima, people from the city gathered annually to celebrate the flowering of the plant in a festival with music and dance, similar to May Day.