869 species are Extinct or Extinct the Wild and this figure rises to 1,159 if the 290 Critically Endangered species tagged as Possibly Extinct are included.

Only 2.7% of the 1.8 million described species have been analyzed.
Overall, a minimum of 16,928 species are threatened with extinction.

Threatened with Extinction:

38% of all fishes in Europe and 28% in Eastern Africa.
At least 17% of the 1,045 shark and ray species are threatened
12.4% of groupers
 6 of the 7 marine turtle species are threatened with extinction.
27% of the 845 species of reef building corals are threatened
20% of reef building corals are Near Threatened
27.5% of marine birds are in danger of extinction
11.8% of terrestrial birds.
33% of amphibians
Nearly 25% of mammals are threatened with extinction.
28% of Conifers
52% of cycads

Data: Vié, J.-C., Hilton-Taylor, C. and Stuart, S.N. (eds.) (2009). Wildlife in a Changing World – An Analysis of the 2008 IUCN Red List of Threatened Species. Gland, Switzerland: IUCN. 180 pp.

Photo Credit:
Asian Wild Ass (Equus hemionus). Threat category Endangered © Jean-Christophe Vié

With frequent new discoveries, the number of valid scientific descriptions of species of fishes is always on the upswing.  Projections from 2006, self-described as conservative, put the eventual number  of living species to be close to 32,500.  Fishbase.org, updated in April 2009, has a searchable database of 31,200 species.

77 A.D.  – ~144 known species
1976 – 18,818 known species, 450 families
1984 – 21,723 known species, 445 families
1994 – 24,618 known species, 482 families
2006 – 27,977 known species, 515 families

Of the total species formally described in 2006, 42.7% (11,952) of species live in freshwater, 55.5% (15,520) of species live in seawater, and 1.8% (505) of species move between freshwater and oceans during their lifecycles. 

• The largest order of fishes is Perciformes that is comprised of 10,033 species, and includes 160 families. Perciformes include fresh and salt water fishes such as gobies, wrasses, sea basses, and cichlids.
• The smallest orders of fishes is Amiiformes  with only 1 specie.  The Amiiformes order is comprised solely with the bowfin, Amia calva which is distributed over the eastern half of North America.
• The greatest diversity geographically is found in the tropics, with the most marine species found in Indo-West Pacific (western Pacific Ocean, Indian Ocean, Red Sea), and the most freshwater species located in Southeast Asia, South America, and Africa.
• The fish found at the highest altitude is the nemacheiline river loach that inhabits hot springs in Tibet at an elevation of just over 17,000 feet (5200 meters).
• At 26,246 feet (8000 meters) below the  surface of the ocean, the cusk-eels are the deepest living fishes.
• Of the total described species, 970 are cartilaginous sharks, skates, rays  and chimaeras.
• The largest living fish is the whale shark which can grow over  40 feet (12 meters) long.
• One of the smallest fish and vertebrate known, with the smallest mature female measuring just  7.9 mm is the Indonesian minnow Paedocypris progenetica.

References:
Nelson, J. S.: Fishes of the World, John Wiley & Sons, Inc. 2006
Helfman, G.S.: The Diversity of Fishes, Blackwell Science, Inc. 1999

ANIMALS:  Estimated 10 million species inhabit the earth. Of this estimate, a little more than 1.3 million have actually been named and described by the scientific community.
Natural rate of extinction described as less than one species per year for every million species.  However, habitat destruction has led experts to estimate the current annual rate of extinction is between 1,000 and 10,000 per million species.

Total Known Animal Species (2008)
Invertebrates – 1.3 million
Fish – 30,300
Birds – 10,000
Reptiles – 8,200
Amphibians – 5,700
Mammals – 5,400

PLANTS:  Approximately 300,000 species of plants have been identified out of a total global number of 320,000

Total known Plant Species (2001)
Flowering plants – 270,000
Conifers – 550
Ferns – 12,000
Cycads – 145
Club mosses – 1,000
Mosses and liverworts – 16,000