Hadn’t the froggiest

Scientists match unusual tadpoles to threatened horned frogs

Scientists at international conservation charity ZSL (Zoological Society of London), Indo-Myanmar Conservation, The Australian Museum and Hoang Lien National Park have identified the tadpoles of six species of Asian horned frogs found in Vietnam’s mountain forests.

Giant horned frog

This research helps solve one of the trickiest zoological puzzles: which tadpoles become which adult frogs. It is relatively simple in the UK where there are just four native species of frogs and toads, but in Vietnam there are more than 270. 

“Frogs and their tadpoles look nothing like each other but it’s important to know which tadpole becomes which frog.” says lead author Benjamin Tapley, ZSL’s Curator of Reptiles and Amphibians. “It helps us detect the presence of a species, especially as adult frogs can be seasonally active and difficult to find, and allows us to identify which places might be important frog breeding sites that need protection.” 

Researchers collected geographical data, took photos and morphological measurements of tadpoles, and compared their DNA to samples from adults of known frog species. 

After this analysis, the team identified and described the tadpoles of: 

  • Mount Fanispan horned frog (Megophrys fansipanensis) 
  • Giant horned frog (Megophrys gigantica) 
  • Hoang Lien horned frog (Megophrys hoanglienensis) 
  • Jingdong horned frog (Megophrys jingdongensis) 
  • Maoson horned frog (Megophrys maosonensis) 
  •  Annam horned frog (Megophrys intermedia) 

All six species belong to the genus Megophrys, known as Asian horned frogs. 

“Horned frog tadpoles are extraordinary looking, with highly-specialised mouth parts which allow them to feed on small particles suspended at the surface of the water.” adds Tapley.  “This adaptation means that the tadpoles can feed in parts of the water column that other tadpoles are unable to.” 


“The more we study Asian horned frogs, the more we learn how diverse and under threat they are. These frogs occur in some of the most exploited forests on earth and are suffering from rapid habitat loss and degradation. Some of the species we have discovered in recent years are only found in a very small area which makes them inherently vulnerable to extinction from habitat loss or stochastic events.” 

A lack of funding - as a result of the current pandemic - has put ZSL’s world-leading expertise in science and conservation in serious jeopardy. ZSL needs urgent support to keep its scientists investigating wildlife diseases such as Covid-19, and its conservationists working in the field to protect the wildlife and ecosystems on which we rely. Find out more and donate at www.zsl.org/donate

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