Early instar swallowtail caterpillar (likely citrus swallowtail)

Larvae occur on citrus and other Rutaceae plants in gardens, orchards, and subtropical woodland.

Chews leaves, primarily on citrus and related host plants. Young larvae often consume leaf margins and new growth.

The caterpillar appears bird-dropping-like, a form of camouflage common in early swallowtail stages. When disturbed, it may evert an orange, forked osmeterium that releases defensive odors; it later pupates attached to vegetation.

Harmless to people and nonvenomous, though it can defoliate young citrus plants. Adults are important flower pollinators, and larvae support predators and parasitoids.