David Fleetham / Schooling Lemon / Milletseed butterflyfish (Chaetodon miliaris) below kayakers off Maui, Hawaii.

David Fleetham / Schooling Lemon butterflyfish (Chaetodon miliaris) near to surface. Maui, Hawaii.

David Fleetham / Looking upwards to schooling Lemon butterflyfish (Chaetodon miliaris) near to surface. Maui, Hawaii.

Ingo Arndt / Lemon / Common lime swallowtail butterfly (Papilio demoleus) on flower head, Asia, Captive

Hanne & Jens Eriksen / Lemon emigrant butterfly (Catopsilia pomona) Thailand, February.

Ingo Arndt / Close-up of wing pattern of Lemon / Common lime swallowtail butterfly (Papilio demoleus) Asia, Captive

Ingo Arndt / Lemon / Common lime swallowtail butterfly (Papilio demoleus) on flower head, Asia, Captive

Ingo Arndt / Lemon / Common lime swallwotail butterfly (Papilio demoleus) on flower head, Asia, Captive

Rod Williams / Chequered / Lime Swallowtail Butterfly (Papilio demoleus). Captive. Endemic to Thailand. UK, June.

Edwin Giesbers / Lemon / Common lime swallowtail butterfly (Papilio demoleus) at rest on leaf.

Aflo / ic-08203 Shoal of Lemon butterflyfish {Chaetodon miliaris} Hawaii, USA.

Jeff Rotman / Diver surrounded by Lemon Butterflyfish (Chaetodon millaris). Hawaii, Pacific Ocean.

Norbert Wu / Lemon Butterflyfish (Chaetodon citrinellus) and Black Durgon (Melichthys niger) schooling, Hawaii

David Fleetham / Schooling milletseed / lemon butterflyfish (Chaetodon miliaris), endemic to Hawaii.

David Fleetham / Lemon / millet butterflyfish (Chaetodon miliaris), Rarotonga, Cook Islands.

David Fleetham / Endemic Lemon / Milletseed butterflyfish (Chaetodon miliaris) and miscellaneous reef fish, swimming around couple snorkeling, Maui, Hawaii.

Etienne Littlefair / Checkered swallowtail butterfly (Papilio demoleus) resting on a plant stem, Adelaide River Hills, Northern Territory, Australia.

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