New Mexico is enormously rich in biodiversity. Across plants and vertebrate animals, New Mexico has the 4th highest native species richness of any of the U.S. states¹. The large size of our state and nearness to the U.S. southern border are major contributers to our species richness. Another important factor is that several ecoregions converge in New Mexico including the Colorado Plateau, the Southern Rocky Mountains, the Arizona-New Mexico Mountains, the Central and Southern Short-grass Prairies, the Chihuahuan Desert, and the Apache Highlands. While these factors contribute to New Mexico's large species richness, the level of endemism (species found only in New Mexico) is relatively low. New Mexico ranks 11th in endemism¹.

Among U.S. states, New Mexico has the 4th highest diversity of plants, 3rd highest diversity of mammals and of reptiles, and the 2nd highest diversity of birds¹. At this time, we do not know invertebrates well enough to say how many species we have in New Mexico or to compare quantitatively against other states (See our page on NM Invertebrate Biodiversity). Nevertheless, it seems quite likely that the species richness of insects, spiders, and other arachnids is quite high in New Mexico. As expected for a dry state, our species richness for amphibians and freshwater fishes is relatively low compared to other states¹ (27th and 38th respectively).

The table below seeks to summarize the number of documented species in New Mexico across the entire taxonomic spectrum. At the present time, we have good estimates for species numbers in vertebrates and vascular plants, but our understanding of the other taxonomic groups is too limited to allow us to offer even a plausable guess as to the number of species. As such, we are a long way from being able to generate a legitimate estimate for the total number of species in New Mexico.

¹B.A. Stein. 2002. States of the Union: Ranking America's Biodiversity. Arlington, Virginia: NatureServe. Available Online.

²K.W. Allred. 2003. Statistical Summary of the Flora of New Mexico. The New Mexico Botanist no. 28:1-7. Available Online.Our understanding of the New Mexico flora is actively growing; for instance, between 1996 and 2002, we added an average of 33 new species to the flora each year.

³Compiled from various sources including Sublette, J.E., M.D. Hatch, and M. Sublette. 1990. The Fishes of New Mexico. University of New Mexico Press, Albuquerque, New Mexico. as well as NMNHP Species Information. From the New Mexico Natural Heritage Program Biological and Conservation Data System, internet version updated May 13, 2004. http://nmnhp.unm.edu/query_bcd/query.html. Accessed 2004-09-15.

⁴C.W. Painter, and J.N. Stuart. 2004. List of Standard English and Current Scientific Names: Amphibians and Reptiles of New Mexico. Accessed 2004-09-15. Available Online.

⁵New Mexico Orthithological Society. 2004. New Mexico Ornithological Society Checklist. Accessed 2004-09-15. Available Online. The number in parentheses for Number of Extant Native Species includes "review species" which are mostly accidentals to the state.

⁶J.K. Frey. 2004. Taxonomy and Distribution of the Mammals of New Mexico: An Annotated Checklist. Occassional Papers of the Museum of Texas Tech University, no. 240:1-32. Frey lists an additional 11 species of possible occurrence in the state.

Citation: Frazier, C.K. 2005. New Mexico Biodiversity and Species Richness. New Mexico Biodiversity Collections Consortium, New Mexico, USA. Available at http://NMBiodiversity.org. (Accessed: [Access Date]).

Page was last reviewed or modified: 2005-05-27