(CNN) -- A flat-faced frogfish, bug-eating slug and carnivorous sea sponge are some of the top new species named by scientists.

They appear on a "top 10" list of new species released Saturday amid warnings from the United Nations that the world is not doing enough to protect vulnerable eco-systems.

"Biodiversity loss is moving ecological systems ever closer to tipping point beyond which they will no longer be able to fulfill their vital functions," said Secretary-General Ban Ki-moon on the International Day for Biological Diversity, which is being marked in 11 countries.

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A report released in late April by researchers from the United Nations Environment Program showed that world leaders had failed on a 2002 commitment to reduce the global rate of biodiversity loss by 2010.

It found that since 1970 animal populations had dropped 30 percent, the area covered by mangroves and sea grasses was down 20 percent and the coverage of living corals had fallen 40 percent.

"The deadline has arrived, yet the deterioration of our natural resources continues apace," the secretary-general said in a statement.

He warned that communities everywhere would "reap the negative consequences," but that the "poorest people and most vulnerable communities will suffer most."

A number of events were held around the world Saturday to mark the International Day of Biodiversity. A garden was created along Paris' Champs-Elysees, children in Brazil were encouraged to dress up as animals, and the European Environment Agency unveiled a "living wall" at its headquarters in Copenhagen, Denmark.

The release of a top 10 list species for 2009 continues an annual tradition that marks the anniversary of the birth of Carolus Linnaeus, who initiated the modern system of classifying plants and animals.

The new list, issued by the International Institute for Species Exploration at Arizona State University, was chosen from 18,225 species new to science in 2008, the most recent year for which data has been compiled. They come from Africa, Indonesia, Madagascar, Myanmar, New Zealand, the Philippines, Thailand, the U.S. and Uruguay.

The new discoveries include a golden orb spider able to spin webs of more than a meter in diameter. It is the first of its species named since 1879.

A minnow with fangs found in Myanmar is the first example of oral teeth-like structure found in the largest family of freshwater fishes. And, the sea slug that eats bugs was an unusual find in Pak Phanang Bay in the Gulf of Thailand as nearly all sacoglossans, or sea slugs, eat algae.

"Most people do not realize just how incomplete our knowledge of Earth's species is or the steady rate at which taxonomists are exploring that diversity," said Quentin Wheeler, director of the International Institute of Species Exploration.