The Secretive Legless Lizard

By Evan Kaiafas

The sand prairie regions of Northwest Indiana and Northeast Illinois are filled with an incredible diversity of reptiles and amphibians. Many of these species are what I like to call “sand specialists” because, through evolution, they have become perfectly equipped to deal with the unique conditions of a sand prairie ecosystem. These conditions include intense heat due to the lack of a thick forest canopy, loose soil, and sparse vegetation for camouflage and cover. Several species may come to mind when you begin to think about these so-called “sand specialists.” The Eastern Hog-nosed Snake is an icon of the northern sand prairie because of its almost comedic array of defense mechanisms. The Blue Racer Snake is another sand specialist because of its incredible speed which it uses to evade predators in areas where hiding spots are few and far between.

However, there is a certain species of lizard that has evolved into the ideal sand prairie specialist. That species is the Western Slender Glass Lizard. The scientific name of this species is Ophisaurus attenuatus which directly translates to “slender snake-lizard.” Through millions of years of evolution, this species of lizard has completely lost all of its limbs. This absence of limbs combined with its slender build and unusually smooth scales allow it to disappear into the loose sandy soil in the blink of an eye. The Glass Lizard is seldom seen above ground by humans, as it only ventures above ground to hunt or to regulate its body temperature. The Glass Lizard is an opportunistic predator as its diet consists of just about anything that will fit into its mouth. This includes, but is not limited to various insects, spiders, small rodents, along with small lizards and snakes. O. attenuatus is the epitome of a sand prairie specialist and it continues to draw interest from herpetologists across its expansive range. As you may guess it is incredibly hard to accurately confirm localities for this species due to the fact that they are nearly impossible for humans to lay their eyes on. So of course I was ecstatic when I found my lifer Western Slender Glass lizard last year.

Through millions of years of evolution, this species of lizard has completely lost all of its limbs.

It was a cool, late September morning on the John Merle Coulter Nature Preserve in Portage. The sun was shining through a shifting blanket of cloud cover. The high for the day would just barely reach 65 degrees. I had gotten to the preserve around 10 o’clock and the temperature was in the high 50’s. I began the short hike that loops around the preserve, keeping my eyes fixed on the sides of the trail. Most snakes will come out to bask on these cool and sunny fall days. Moving at a very leisurely pace while searching for any long scaly objects in the low-lying vegetation, I spotted one of the man-made logs that litter the Coulter property. I knew from personal experience that many species of reptiles and amphibians liked to shelter under these logs. I turned over the log and was stunned when my eyes were met by a juvenile Glass Lizard stretched out underneath.

This was one of my favorite finds from 2020. Not only are these lizards super interesting to observe in person but I was crushed to find a roadkill Glass Lizard on one of the roads that borders the Coulter Preserve. So if you are visiting the John Merle Coulter Nature Preserve in the future, keep your eyes peeled while on the trail and on the roads near the preserve. Vehicular deaths are one of the leading causes of herpetological population decreases in recent years. We are fortunate that the Shirley Heinze Land Trust along with the Indiana Dunes National Park still provide protected healthy habitat for these fascinating creatures.