Dirk Stevenson (Altamaha Environmental Consulting)
The morning sun warms the bark of a massive longleaf pine, one of many thousands that stand tall in the gorgeous mesic savannah. I find comfort in the strength of the columnar trunk, art in its fire scars, knobs and furrows. I pat the tree, exfoliating scales of bark. The ringing calls of ornate chorus frogs erupt from a nearby cypress dome. The Apalachicola National Forest is a fine place to get some thinking done, and I am pondering an odd and poorly known group of reptiles which thrive here, our glass lizards.
Some background on our Ophisaurus fauna
Members of the Family Anguidae (the Glass and Alligator Lizards) possess osteoderms beneath their scales. Deep, lateral folds, running from the neck to the vent and lined with tiny scales, allow for expansion of a rigid, hard body. The alligator lizards, with scalation that lends a crocodilian appearance, include a half-dozen species native to the western U.S. as well as 30 species of bizarre, beautiful, and in many cases endangered, neotropical lizards (genus Abronia) that are flagship species for imperiled Mesoamerican cloud forests. According to lizard specialist Lance McBrayer of Georgia Southern University, vomerofaction - using the tongue and a unique organ in the nasal cavity called the Jacobsen’s organ - is well developed in anguids. “These lizards flick the tongue out to pick up heavy molecular weight compounds, some from the air and lots from the substrate. They use that tongue to smell and to detect prey, and can trail those prey with it, just like a monitor.
The legless glass lizards (Ophisaurus spp., with 4 species native to the southeastern United States) are dang tough to identify until you have seen a lot of them. I recommend repeated ogling of every photo you can find on-line and a copy of the recently minted Amphibians and Reptiles of Florida (Krysko et al. 2019). All ophisaurs seem to be a good bit fossorial and underground much of the time. In 1991, new to central Florida, my friend Geech used a colloquialism for glass lizards that I had not heard before. A weathered hunter and lifelong rancher, Geech managed a vast tract close to Lake Panasoffkee. He had an interesting way of speaking. “Now watch out, ‘cause he be waiting for you!” is how he described encounters with big diamondbacks resting coiled near his quail feeders. One day we shot the bull as he dressed a wild hog under a small tin-roof shelter in a live oak hammock. The veins in his muscular forearms stood out in relief. Sweat dripped onto the Winston cigarette that bounced between his lips as he spoke of the many “joint snakes” he had plowed up over the years in his food plots (which were disturbed sandhills). I do hear glass snakes from the locals in S GA.
By far our most abundant is the eastern glass lizard, O. ventralis. Easterns have gently rounded snoots, lack dark pigment below the groove, and possess a clean lemon-yellow undercarriage. Some older individuals have pretty emerald green backs. Although they may be found in tortoise country, they prefer more mesic conditions. In south Georgia, they do well in suburbs and on barrier islands. My friend Chris has a good population in his backyard− a humid jungle landscaped with avocado and pomegranate and sporting mulch piles and boards− in downtown Brunswick.
The much less common and locally distributed eastern slender glass lizard (O. attenuatus longicaudus) has a more pointed nose, is equally large (those with complete tails may exceed 40 inches in total length) and does have dark marking below the lateral fold as well as a middorsal stripe. An inhabitant of better drained habitats, attenuatus is often present in longleaf pine – turkey oak sandhills. Adult males, patterned like a Navajo blanket with golden bands outlined in black, are absolutely stunning.
Island glass lizards (O. compressus) have a willowy habitus, even for a glass lizard, and a curious distribution: they are found in xeric scrub, sandy pine-palmetto communities, and on some barrier islands. Open pineland environs of the Everglades region support this species. Along with dusky pigmy rattlers, as a younger man I found them in numbers during the last hour of daylight, that magic time for road-cruising, on Turner River Road in Big Cypress National Preserve (This was long before constrictors capable of dispatching deer (Python bivittatus) invaded the region). They possess bold dorsolateral stripes and are our only glass lizard lacking fracture planes in the tail.
Although generally mild-mannered, if you grab a large ventralis or attenuatus − that is moving overland, fast, in an effort to escape − all hell breaks loose. The lizard may turn, bite, hang on and gator-roll. Sections of tail disengage from the lizard, bouncing about on the ground (along with small pieces of your palm and/or fingers). Glass lizards are mostly (70%) tail. It is common to find eastern and slender glass lizards which have autotomized, then regrown, parts of their tails. Remarkably, a large eastern glass lizard that I pursued, but never touched, became agitated and broke off the last 8 inches of its tail. I could have sworn that at one point it crawled backwards.
In Pursuit of Mimicus
In 2021, I embark on a quest to learn as much as I can about the mimic glass lizard (O. mimicus). I hope to rediscover the species in Georgia. First described to science in only 1987, mimicus is enigmatic, secretive, fossorial, and beautiful. The species is seldom field-collected, the vast majority of records are known from specimens found on roads or in funnel traps placed along drift fences. It was last documented here in 1993. It was last confirmed in Mississippi in 1955, and South Carolina in 1984. A single extant site is known from southern Alabama. You get the picture.
In the riveting Liberty County portion of Apalachicola National Forest, located southwest of Tallahassee in the eastern part of the Florida panhandle, I link with Pierson Hill of the Florida Fish and Wildlife Conservation Commission. Henry David Thoreau wrote, to paraphrase, there is no point in ever giving another man advice. True, but if you haven’t you need to visit the ANF, to experience what much of our Coastal Plain once looked like. Lots, lots of snakes, too.
Pierson glides through the pinewoods with an easy grace; his vision seems comparable to that of the bald eagle we meet at dawn, on a new cottonmouth roadkill. He leads me to several sites on the forest where he has encountered mimicus. Last spring, he espied one as it attempted to escape into a crawfish burrow. Because of the importance of its burrows to a wide variety of animals, her playfully refers to the abundant Procambarus rogersi as “the gopher tortoise of the flatwoods”
Pierson becomes melancholic when discussing the past – what was – and the future of these diverse savanna ecosystems. “What we (field biologists) mostly do now is study declines, and hope that somehow we can come up with viable plans to keep these species from extinction”, he tells me.
Many landscapes that support flatwoods salamander populations are/were known mimicus sites. Both herps evolved to require naturally-functioning, mesic longleaf pine savannas maintained by regular growing season (May-August) burns. You don’t have to be a glass snake fanatic to love mimicus habitats, the crème de la crème of what remains, longleaf pine savanna-wise (portions of De Soto National Forest, Sandhill Crane NWR, Blackwater River State Forest, Conecuh National Forest, Fort Stewart, Croatan National Forest), are sites where even those wearing herp goggles are easily distracted by a plethora of pulchritudinous, meat-eating plants (pitcher plants, butterworts, sundews, and in the North Carolina range of mimicus, Venus fly-traps). These plants and countless other heliophiles form wonderful gardens of graminoids. Any degree of serious soil disturbance to such luxurious ground covers, and the absence of fire, are deal-breakers
In Bill Palmer’s Footsteps
The discovery of the mimic glass lizard is a compelling story. In the 1980s, North Carolina herpetologist William Palmer noticed some O. attenuatus-like specimens in his state that appeared atypical. (Interestingly, about the same time Robert Mount of Alabama had flagged some preserved specimens in the Auburn University collection as atypical attenuatus as well). Subsequently, Palmer conducted a comprehensive review of all glass lizard museum material available from the southeastern U.S., then described the new form. Its specific epithet is a tribute to its close resemblance to O. attenuatus.
Most of the mimicus specimens examined by Palmer, collected from the 1950s-early 1980s, were found, alive or dead, on roads (AOR or DOR, respectively). A glass lizard on a road appears lustrous, like a coral or mud snake. Most of us came after the heyday of road-cruising (i.e., 1950s – 1970s) when narrow paved roads that one could safely drive without having graduated from the local NASCAR academy still passed through intact longleaf pine and other habitats. I visited the herpetology collections at the University of Georgia and at Georgia Southern University to examine some pickled mimicus. Despite many decades in formalin/ethanol the specimens were well-preserved, albeit the golden-yellow colors of the dorsum long faded to tan.
It was moving to read the names of the herpetologists and naturalists who had collected some of these – including the late Osierfield, Georgia naturalist Milton Hopkins (a darter, Etheostoma hopkinsi, is named for Milton). He was a good friend. The lone specimen collected from Wayne County, Georgia was found road-cruising in 1953 by Dennis Paulson (now a world expert on Odonata). This part of Georgia has been swallowed by industrial forestry.
We need to work hard to learn more about the mimic glass lizard. Let’s hope there is a future for this legless denizen of the longleaf, the one who swims in knee deep wiregrass.
Krysko, K.L., K.M. Enge, and P.E. Moler (Eds.). 2019. Amphibians and Reptiles of Florida. University of Florida Press, Gainesville, Florida, USA.