-LRB- CNN -RRB- -- A pea-sized seahorse , the world 's longest insect , a `` ghost slug '' and the world 's smallest snake were among the top 10 species discovered in 2008 , a committee of scientists said Friday . A tiny seahorse and the world 's longest insect were among the top 10 new species discovered in 2008 . These unusual critters were among thousands of species found last year , many in remote or tropical regions of the planet , that hint at the breadth of the Earth 's undiscovered biodiversity . `` Most people do not realize just how incomplete our knowledge of Earth 's species is , '' said Quentin Wheeler , director of the International Institute for Species Exploration at Arizona State University , which announced the top 10 new species list . `` We are surrounded by such an exuberance of species diversity that we too often take it for granted , '' Wheeler added . The ASU institute and an international committee of taxonomists -- scientists devoted to species exploration and classification -- compile the top 10 list of new species each year . Also on the 2008 list are a caffeine-free coffee plant , a snail whose shell twists around four axes , a palm that flowers itself to death and microscopic bacteria that live in hairspray . See photos of the new species '' Here 's the complete list : 1 . Pygmy seahorse : Classified by its Latin name , Hippocampus satomiae , this species measures about half an inch long and was found near Derawan Island off Kalimantan , Indonesia . 2 . A plant that kills itself : Found in a small area of northwestern Madagascar , a rare genus of palm -- Tahina spectablilis -- produces huge , spectacular flowers and then dies and collapses . Fewer than 100 have been found . 3 . Decaf , please : Known as Coffea charrieriana , this plant found in Cameroon is the first record of a caffeine-free coffee species from Central Africa . 4 . Spray-on species : An extremophile bacteria , Microbacterium hatanonis , was discovered in hairspray by Japanese scientists . 5 . A stick that moves : The world 's longest insect , with a body length of 14 inches -LRB- 22.3 inches including legs -RRB- , Phobaeticus chani resembles a stick and was found in Borneo , Malaysia . 6 . The Barbados Threadsnake : Leptotyphlops carlae measures only 4.1 inches long and is believed to be the world 's smallest snake . 7 . A pale `` ghost slug '' : Selenochlamys ysbryda was a surprising find in the densely populated area of Cardiff , Wales . 8 . A very limber snail : This unique species , Opisthostoma vermiculum , is found on a limestone hill in Malaysia and has a shell that twists around four axes . 9 . Damsel in the deep blue sea : Chromis abyssus is a beautiful species of damselfish found in deep-reef habitat off the coast of Ngemelis Island , Palau . 10 . Fossil mama : A fossilized fish , Materpiscis attenboroughi , is an extremely rare find from Western Australia and shows a mother giving birth 380 million years ago . Scientists are still classifying species found around the globe in 2008 , so final data for that year are not available . But on Friday , the taxonomists issued a State of Observed Species report card that states 18,516 species new to science -- about half of them insects -- were discovered and described in 2007 . The vast majority of the 18,516 species named in 2007 were invertebrate animals -LRB- 75.6 percent -RRB- , vascular plants -LRB- 11.1 percent -RRB- and vertebrates -LRB- 6.7 percent -RRB- . The report was compiled by ASU 's International Institute for Species Exploration in partnership with other scientists . `` Charting the species of the world and their unique attributes are essential parts of understanding the history of life , '' Wheeler said . `` It is in our own self-interest as we face the challenges of living on a rapidly changing planet . '' According to Wheeler , a new generation of tools is coming online that will vastly accelerate the rate at which humans can discover and describe species . The annual release of the top 10 new species list and State of Observed Species report commemorate the anniversary of the birth of Carolus Linnaeus , who initiated the modern system of plant and animal names and classifications . An estimated 1.8 million species have been described since Linnaeus initiated the modern systems for naming plants and animals in the 18th century . Scientists estimate that there are between 2 million and 100 million species on Earth , though most set the number closer to 10 million , according to ASU . `` It is estimated that the approximately 1.8 million species named since 1758 represent no more than a fraction of the world 's species , '' the report states . `` Rapid environmental changes around the world highlight the urgent need to accelerate our exploration of Earth 's species , '' the report says . `` Millions of species -- the majority not yet known to science -- face an uncertain future . Among these species are keys to understanding the history of the origin and diversification of life on our planet . ''