World’s Smallest Reptile Discovered in Madagascar: Meet the Nano-Chameleon
Scientists have discovered two of what may be the world’s smallest reptile, a miniature chameleon subspecies the size of a sunflower seed.
Already, the species is presumed threatened by extinction due to deforestation in the montane rainforests of northern Madagascar. However, since the discovery, efforts to protect the Sorata Massif forests may save the wee chameleons.
“The nano-chameleon’s habitat has unfortunately been subject to deforestation, but the area was placed under protection recently, so the species will survive,” said Oliver Hawlitschek, a scientist at the Center of Natural History in Hamburg.
These tiny chameleons are much more than a curiosity, offering scientists a look into ancient evolutionary history.
The Nano-Chameleon, Brookesia nana
Now, the male nano-Chameleon, Brookesia nana, is presumed the world’s smallest reptile. It can comfortably rest on your fingertip at 22mm (0.86in) from top to tail. Notably, females are significantly bigger, at around 29mm (1.14in). Size dimorphism between the sexes is widespread in chameleons, including Brookesia.
The word “nano” was chosen from the prefix “nano,” as in nanotechnology, indicating a very small size, notes the study authors.
Tiny But Well-Endowed
Despite its small size, the male has proportionally large genitalia called hemipenes. That prompted the researchers to look at other chameleons. As a result, they learned that the smallest chameleons tend to have proportionally larger genitalia. Possibly, this is to ensure that sexual reproduction remains functional despite sexual dimorphism.
IFL Science discussed the “surprisingly” well-endowed reptile:
“Occasionally, a male may choose to ‘air out the bits’ and flex them about, and they also get them out for mating. Amazingly, when out and proud, the hemipenes of B. nana are roughly 18.5 percent of its body size,” noted IFL Science.
Below, artist Mesa Schumacher depicts the tiny wonder, complete with a hat!
World’s Smallest Reptile and Amniote Vertebrate
The species feeds for mites on the forest floor and hides at night in blades of grass, the researchers determined.
Dr. Mark D. Scherz, one of the researchers involved, noted in his blog that the chameleons might also be the smallest amniote vertebrate in the world! Amniota is a group of limbed vertebrates that includes all living reptiles, birds, and mammals, notes Britannica.
Scherz calls the nano-chameleon a “spectacular case of extreme miniaturization.” And he should know because his colleagues reported on another tiny chameleon nine years ago. In 2012, researchers announced discovering Brookesia micra, a related tiny chameleon also from Northern Madagascar.
Today, some people confuse the two chameleons, but Brookesia nana has now topped Brookesia micra as the world’s smallest reptile. Both remain in the top five smallest reptiles on earth, notes Scherz.
Tiny Relative, Brookesia micra
When scientists discovered Brookesia micra in 2012, it made news around the world. Adults are just over an inch from nose to tail. Unlike some larger chameleons, they remain drab, blending into the background.
“Although these small, drab, and cryptic species are not what come to mind when most people think of typical chameleons … they may, in fact, more closely resemble the ancestral proto-chameleon than the larger and often brilliantly colored species so familiar to us all,” said researcher Ted Townsend.
Townsend tested the chameleon’s DNA, discovering they were a distinct and “very ancient species.” At the time, he said he suspected even smaller chameleons might exist, and he was right.
As far back as 10 to 20 million years ago, Brookesia micra may have diverged from other leaf chameleon species. For some reason, this area of Madagascar favored tiny chameleons. Now, it’s a subject of ongoing interest with the discovery of the even smaller subspecies.
Perhaps, the chameleons were able to fill a niche left open in the food chain.
“Miniaturization and gigantism on islands has been talked about for at least the last 150 years of evolutionary biology,” Townsend said. “We don’t really know why it happens, but a lot of peoples’ theory is that there is an ecological opportunity. Maybe on these islands, there weren’t any insects that took this (chameleon’s) ecological place, so there was this opportunity for these little lizards — which already were very small — to exploit extra-tiny prey like little mites.”
Being tiny, the chameleons may live their entire lives in a few square miles. Thus, they are also extremely vulnerable to habit loss.
Tiny Geckos, Fish, Frogs
A gecko species from the Caribbean, Sphaerodactylus ariasae is a close competitor for the world’s smallest reptile. The gecko’s body length is around 16mm (0.62in). Due to its relatively long tail length, nano-chameleon is smaller.
Other related geckos in the genus are similarly tiny, as you can see below.
In 2018, Dr. Scherz tweeted that the world’s smallest vertebrate might be a tiny fish, Paedocypris progenetica.
Then, the world’s smallest frog might be Paedophryne amauensis, the size of a fly.
Scientists found hundreds of new species in 2020. Now, in 2021 we already have the amazing discovery of the world’s smallest reptile. All the time, we’re learning more wonderful things about our amazing wildlife.
Earth’s spectacular biodiversity is astonishing and worth protecting and preserving forever. Let’s all do what we can to protect our wonderful wildlife.
See more about Brookesia nana below from SciNews:
Featured image: Screenshot via YouTube