Newly Discovered ‘Nano-Chameleon’ Is World’s Smallest Known Reptile
A teeny-tiny species of chameleon, believed to the smallest reptile in the world, has been discovered by scientists on the island of Madagascar.
The adorable little creatures – known as Brookesia nana or the nano-chameleon – are so small they can fit on the tip of a human finger.
Just two nano-chameleons have been found so far, but fortunately for researchers one is male and the other is female, allowing them to analyse any differences between the two sexes.
The female’s body is just 19mm, or 29mm including the tail, which puts the miniature creature among the smallest geckos and chameleons.
Meanwhile, the male’s body is just 13.5mm, or 22mm including the tail, which would appear to make it the smallest reptile in the world, beating the former smallest reptile by just half a millimetre.
‘At a body length of just 13.5mm and a total length of just 22mm including the tail, the male Nano-Chameleon is the smallest known male of all higher vertebrates,’ explained Frank Glaw, the first author of the study, which was published in Scientific Reports.
The closest relative of the new chameleon is also not the similarly tiny Brookesia micra, but instead the nearly twice as large B. karchei, which occurs in the same mountains. That shows that this extreme miniaturisation has arisen convergently in these chameleons,’ study co-author Jörn Köhler wrote.
The international team, led by the Bavarian State Collection of Zoology, did CT scans on the nano-chameleons to ensure they were fully grown, and quickly discovered that the female had eggs inside her and the male’s genitalia seemed to be well developed, suggesting they are both mature.
Interestingly, scientists discovered that this particular part of the male’s anatomy wasn’t ‘nano’ at all; well, not compared to the rest of him. The male’s genitals made up almost 20% of his entire body, which the researchers explained would be needed to mate with females, who are significantly bigger, in something that is called ‘sexual size dismorphia’.
However, why the nano-chameleons are so small remains unknown, as the usual reasons for species need to shrink in size for survival don’t appear to match with the miniature creatures’ habitat.
‘There are numerous extremely miniaturised vertebrates in Madagascar, including the smallest primates and some of the smallest frogs in the world, which have evolved independently,’ co-author Andolalao Rakotoarison explained.
‘The island effect that causes species on small islands to get smaller in body size, which has been invoked for other small chameleons, does not make sense in this case, because Brookesia nana lives in the mountains on mainland Madagascar,’ added Fanomezana Ratsoavina.
Sadly, the area where the nano-chameleons live is at risk of deforestation, however it has recently been designated as a protected area, which hopefully will allow the species to survive.
If you have a story you want to tell, send it to UNILAD via [email protected]