This adaptation is to feed on flowers with long corollas such as Passiflora mixta.
''Passiflora xishuangbannaensis | Passiflora vitifolia | Passiflora tarminiana | Passiflora nitida | Passiflora mixta | Passiflora ligularis | Passiflora foetida | Passiflora edulis | Passiflora capsularis |