This is a very tricky question to answer, but arguably the Bajii (Yangtze River Dolphin) would be up there.
Other than that the Saola (Pseudoryx nghetinsis) has only been seen via a camera trap and in bushmeat markets.
Other contenders would include the African Golden Cat, Ethiopian Mole Rat, Attenborough's Short-Beaked Echinda and the Snow Leopard. I'm sure there are a multitude of arboreal tropical murids that would be very difficult to spot in the wild without the use of traps.
Of course the above are all mammals. There are dozens of reptile species that only exist on remote island cliffs and the same can be said about various insect and bird species (i.e. the Fijian Petrel)
That's kind of impossible to answer because so many animals are being discovered all the time, so it's kind of hard to know how many we don't know about, because we DON'T know, get it?
The most unknown animal that ever existed was The Coalacanth that was last found in 1974, 6.9 Thousand Meters under the water but it was supposed to have died out 65 Million years ago!
how would anyone be able to answer your question? if the animal is unknown then we don't know about it therefor your question is unanswerable.
Horse should be the most surefooted animal. Horse should be the most surefooted animal.
The most graceful animal is the swan.
what british animal has most fleas
it is an animal
The most dangerous snake in Arizona is the rattlesnake.
Discuss why good governance has been elusive in most african countries
Even its not official, uruguay's national animal is a bird, it is the Rufous Hornero that is all over our countryside.
I - Almost Got Away with It 2010 Most Elusive Criminals was released on: USA: 2 October 2012
Elusive means sneaky, rare, or hard to find. Elusive people or things are often hiding and difficult to see or catch. For example, a spy, a rare animal, or bigfoot could be considered elusive.
Elusive Butterfly was created in 1966.
Elusive Isabel was created in 1909.
Elusive Isabel has 273 pages.
My Elusive Dreams was created in 1967-06.
This book is very elusive, it is one of a kind.
The duration of The Elusive Pimpernel is 1.82 hours.
The duration of The Elusive Corporal is 1.75 hours.
The solution to the problem remained elusive despite hours of searching.