Would there be like some huge encyclopaedia with every animal with a short ten or fifteen word description and a picture?(if there is I really want one).
I'm afraid the answer is, "No." First of all, there are over 1 million known species of animals and the total number of animals may be 30 million. As far as I know, no scientific institution has a full list of known insect species. Even if someone had a full list of species, I doubt if an encyclopaedia with 10-15 word descriptions of every species of animal would sell. Some species only differ microscopically and a long list of very similar nematode worms would probably be uninteresting to non-specialists. Probably, your best bet is either using Wikipedia (https://en.wikipedia.org/wiki/Animal#Groups_of_animals), the Encyclopedia of Life (Tree of Life) or Tree of Life (Animals). You need to question if you really want to know the name of every animal species. It may be easier for you to choose a group of animals and find out about the animals it includes, rather than going for the whole lot.
A great start would be DK's 'Animal', a book I can't recommend highly enough for those with a growing and diverse interest. [ame=http://www.amazon.co.uk/Animal-DK/dp/1405362332/ref=sr_1_1?s=books&ie=UTF8&qid=1445155980&sr=1-1&keywords=animal]Animal: Amazon.co.uk: DK: 9781405362337: Books[/ame] Similarly, for more specific interests, the series includes 'Bird', 'Ocean', 'Animal Life' and 'The Natural History Book'. These were one of the safest bets if you ever had to give a gift to a pre-teen devilfish.
Devilfish, recognizing the front pages, is this the updated one to this one of the one before? As I own this and it's pretty outdated:[ame=http://www.amazon.co.uk/Animal-definitive-visual-worlds-wildlife/dp/0751334278/ref=sr_1_12?s=books&ie=UTF8&qid=1445169660&sr=1-12&keywords=Animal]Animal: The definitive visual guide to the world's wildlife: Amazon.co.uk: David Burnie: 9780751334272: Books[/ame]
A pre-teen FunkyGibbon was also delighted to receive this one Christmas. I still dip into it from time to time, but its limitations in both breadth and depth became all too obvious a long time ago. It's a good example of why the book the original poster is looking for can never exist. At nineteen pounds including postage it's an absolute bargain though, and maybe worth buying if you don't already own something better.
It is the same book but I don't think it's been significantly changed - I remember coming across it a while back and just checking whether some of the (very minor) mistakes were still there. They were.
Worth considering, at least for mammals: https://books.google.com/books/about/Walker_s_Mammals_of_the_World.html?id=T37sFCl43E8C
