The larvae are solitary and feed on Dilkea (Passifloraceae) species.

[1] Adult H. demeter are distinguished morphologically from their sister species Heliconius eratosignis because they have a yellow streak on the base of the forewing costa underside;[1] in contrast, Heliconius eratosignis has a solid orange basal costal margin on the underside of the forewing.

Brown & Benson in 1975 recognized these differences but argued that the two forms were subspecies of the same species.

They also recorded both Heliconius eratosignis gregarious and H. demeter solitary larvae in their paper.

[2] The Tree of Life web project has yet to recognize Heliconius eratosignis as a separate species, but shows an image of a male Heliconius eratosignis from Peru under the description of H.