Paul Harcourt Davies / Caterpillar of Common yellow swallowtail butterfly (Papilio machaon), dark morph, feeding on Common rue (Ruta graveolens) as a foodplant, Umbria, Italy. October.

Paul Harcourt Davies / Caterpillar of Common yellow swallowtail butterfly (Papilio machaon), dark morph, on Common rue (Ruta graveolens) as a foodplant, Umbria, Italy. October.

Paul Harcourt Davies / Caterpillar of Common yellow swallowtail butterfly (Papilio machaon) on Common rue (Ruta graveolens) as a foodplant, Umbria, Italy. October.

Eladio Fernandez / A lime butterfly (Papilio demoleus) rests on a leaf after a light rain in the Jardin Botanico de Santo Domingo. This butterfly species is a recent introduction to island of Hispaniola (Dominican Repub...

Eladio Fernandez / A lime butterfly (Papilio demoleus) rests on a leaf after a light rain the Jardin Botanico de Santo Domingo, Dominican Republic. This species was introduced and feeds primarily on citrus. Sometimes it...

Ernie Janes / Common lime swallowtail (Papilio demoleus) captive.