A Giant Lizard Walks in....

Nope, not a bar joke. If this blog has a theme, it's that we don't know the world around us as well as we think.  On the small Pacific island of Mussau, we've just discovered the top predator, a blue-tailed monitor lizard that lives nowhere else. Varanus semotus can be over a meter long.

While this is the first new monitor from the Papua New Guinea archipelago in 20 years, monitors in general turn up surprisingly often for such large creatures. Interested researchers like German zoologist Wolfgang Boehme have only recently documented just how widespread and  diverse monitors are. A total of sixteen species were from Indonesia and surrounding islands just between 1990 and 2006. Australia’s count has also risen recently, approaching 30 species, with several known but yet to be named.

Smaller monitors are popular as pets, a fact which has led to several recent discoveries.  A 1998 article by Jeff Lemm in Reptiles magazine discussed eight new types, all of which have turned up in the pet trade.  Two species have been formally described, and there may be as many as six more awaiting description.  Lemm wrote that some of these may prove to be subspecies or varieties rather than species.

From the island of Halmahera came Varanus yowoni, the black-backed mangrove monitor, which may be five feet long.  The other described species Lemm mentioned was the smaller, bright-yellow quince monitor, Varanus melinus.  This lizard grows to almost four feet in length and is reportedly a very tractable species in captivity.  It was kept as a pet and even bred in the United States for years before being identified as a species.

In 1999, Dr. Robert Sprackland described another species, the peacock monitor Varanus auffenbergi.  This is a colorful animal, blue with turquoise and orange markings, plus bright yellow spots on its limbs. Smaller than the other new monitors, it was obtained from Roti island in Indonesia.

Some new species are harder to place.  It’s often the case that a type specimen is in hand, but the type location is unknown. Because of the mixing of sources and suppliers in the pet business, it’s uncertain where several recently described species of new monitors originated. Wherever they came from, the most interesting thing is that, until recently, the scientific world had been quite unaware of them.
Some additional references:

Anonymous. 1997.  “At Home in the Rocks, a New Gecko Emerges,” National Geographic, June.

Lemm, Jeff.  1998.  “Year of the Monitor: A Look at Some Recently Discovered Varanids,” Reptiles, September, p.70.

Reptile Exotics.  No date.  “Care Sheet – Varanus melinus,” http://www.reptileexotics.com/melinus.html.

Sprackland, Robert.  1999.  “A new species of monitor from Indonesia,” Reptile Hobbyist, February.

Sweet, Samuel., and Eric Pianka.  2003.  “The Lizard Kings,” Natural History, November, p.40...  .