Zebra Longwing (Heliconius charitonia) Butterfly. The arrangement of vertical and horizontal stripes on its wings gives rise to its common name. If you compare the wing shape of members of the subfamily 'Heliconiinae' with other butterflies, you will observe that they are relatively long and narrow, hence the name, Longwings. The caterpillars feed on passion vine and accumulate toxins that they pass on to the butterfly. The bright black and yellow patterns warn predators they are poisonous. Zebra Longwings, like other butterflies, mate as adults but are also known to exhibit a behavior called 'pupal mating.' The newly emerged males will actually mate with the female while she is still in the pupal stage. So. Deerfield, MA; 'Magic Wings' Butterfly Conservatory.