A thorny frog which changes colour was discovered in the wildlife rich Greater Mekong region where 23,530 species have so far been discovered, the Worldwide Fund for Nature reported.

Among the 2216 new species discovered between 1997 to 2014, some have power of mind control, if only the minds of cockroaches.

The dementor wasp, named after a Harry Potter character, can render cockroaches their zombie slaves with a sting to the belly.

• New Japan volcanic island ‘a natural lab’ for life
• Rare Omura’s whale washes up on WA beach
• Queen sends birthday letter to cockatoo

Visitors to the Berlin natural history museum voted to name the wasp Ampulex Dementor after the wraith-like monsters from the Harry Potter series who, by sucking the hope and happiness from their prey, turn them soulless.

The wasp on the other hand turns its prey into immobile food, which after stinging it with a venom disables the roach’s powers of self-guided movement, then drags it by the antenna to a safe shelter to feast.

One of the new plant species identified at a Bangkok market was nearly kept secret over fears its publicity could mean doom for the rare orchid.

The orchid’s name has been kept out of the report, a measure to avoid attracting collectors, after a Malaysian orchid’s discovery led to a spike in its online auction price from tens to hundreds of dollars, WWF reported.

“When a species is considered rare, wildlife collectors who prize novelty will rush to own a specimen, creating sharp spikes in trade of that species,” the WWF report stated.

But biologist and endangered species campaigner Dr Jodi Rowley put the case for disclosing species. She said “it’s very hard to conserve something we don’t know exists”.

Dr Rowley discovered the thorny frog, which among its many rare features changes colour from pink-yellow during the night to a dull brown in the day, also ranks among the two per cent of frogs that breed in small water catchments in trees.

But the most unusual aspect of the frogs is their sandpaper-like thorns along the male’s back, which researchers suspect play a part in letting females recognise their breeding condition, depending on “how thorny they are,” according to the report.