Edwin Giesbers / Lemon-yellow tree frog (Hyla savignyi) climbing up grass stem. Cyprus. April.

Edwin Giesbers / Lemon-yellow tree frog (Hyla savignyi) Cyprus. April.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

Shane Gross / Lemon shark pup (Negaprion brevirostris) in mangrove forest which acts as a nursery for juveniles of this species. Eleuthera, Bahamas.

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

David Fleetham / Lemon sharks (Negaprion brevirostris) viewed from below. West End, Grand Bahamas, Caribbean.

David Fleetham / Lemon shark (Negaprion brevirostris) viewed from below. West End, Grand Bahamas, Caribbean.

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

Franco Banfi / Lemon shark (Negaprion brevirostris) Northern Bahamas, Caribbean Sea, Atlantic Ocean