Chien Lee / Giant Crab Spider (Sparassidae) feeding on tree frog prey, Digul River, Papua, Indonesia

Pete Oxford / Giant leaf frog (Phyllomedusa bicolor) climbing along branch in rainforest, Iwokrama Reserve, Guyana

Pete Oxford / Giant leaf frog (Phyllomedusa bicolor) climbing along branch in rainforest, Iwokrama Reserve, Guyana

Pete Oxford / Cane Toad (Bufo marinus) on riverbank, Essequibo River, Iwokrama Rainforest Reserve, Guyana

Chien Lee / Giant Crab Spider (Sparassidae) feeding on tree frog prey, Digul River, Papua, Indonesia

Jaymi Heimbuch / Cane Toad (Bufo marinus) near waterfall, Osa Peninsula, Costa Rica

Alex Hyde / Giant river frog (Limnonectes leporinus) on muddy riverbank at night, Danum Valley, Sabah, Borneo.

Daniel Heuclin / Asian giant toad / river toad (Phrynoidis asper) in cave, Taman Negara, Malaysia, March.

Daniel Heuclin / Asian giant toad / river toad (Phrynoidis asper) in cave, Taman Negara, Malaysia, March.

MYN / Andrew Snyder / Giant Waxy Monkey Tree frog (Phyllomedusa bicolor), Berbice River, Guyana, September. Meetyourneighbours.net project.

MYN / Andrew Snyder / Giant Waxy Monkey Tree frog (Phyllomedusa bicolor), Berbice River, Guyana, September. Meetyourneighbours.net project.

Chien Lee / Giant River Frog (Limnonectes leporinus), Tibu, Batang Ai National Park, Malaysia

Chien Lee / Giant River Toad (Bufo juxtasper), Lubang Buaya, Batang Ai National Park, Malaysia

Chien Lee / Giant River Frog (Limnonectes leporinus) camouflaged against leaf litter, Lubang Buaya, Batang Ai National Park, Malaysia

Chris Mattison / Giant River Frog (Limnonectes leporinus) Danum Valley, Sabah, Borneo.

Konrad Wothe / Marine Toad (Rhinella marinus) in rainforest at Tambopata river, Tambopata National Reserve, Peru, South America.

Yukihiro Fukuda / Japanese giant salamander (Andrias japonicus) in river with frog prey, Japan, March

Pete Oxford / Giant Gladiator Treefrog (Hypsiboas boans) egg spawn in mud nest, Rewa River, Iwokrama Rainforest Reserve, Guyana

Pete Oxford / Giant Gladiator Treefrog (Hypsiboas boans), Rewa River, Guyana

Pete Oxford / Giant Gladiator Treefrog (Hypsiboas boans) egg spawn in mud nest, Rewa River, Iwokrama Rainforest Reserve, Guyana

Pete Oxford / Giant Gladiator Treefrog (Hypsiboas boans) male and female in mud nest, Rewa River, Guyana

Tim Laman / Head portrait of a Giant River frog (Limnonectes leporinus) with a mosquito biting its nose, Borneo, Malaysia

Chien Lee / Giant River Frog (Limnonectes leporinus) camouflaged in leaf litter, Danum Valley Conservation Area, Borneo, Malaysia

Pete Oxford / Cane Toad (Bufo marinus) on rock, Boca Mishagua River, Amazon ecosystem, Peru

Suzi Eszterhas / Giant River Toad (Bufo juxtasper), Danum Valley Conservation Area, Malaysia

Robert Valentic / Giant frog (Cyclorana australis) breeding male, from a river gorge, Queensland, Australia. Controlled conditions.

Tim Laman / White-lipped tree frog (Litoria infrafrenata) in gallery forest along the Archer River. Piccaninny Plains Sanctuary, Cape York Peninsula, Queensland, Australia