Panama is the kind of country where a walk through a garden, along a jungle trail or even around a hostel can reveal a surprising amount of wildlife. You might see an anole basking on a wall, a gecko disappearing behind a light, or a basilisk sprinting across a stream.
And then there are the skinks.
Skinks are some of the more easily overlooked lizards in Panama. They tend to be small, fast and somewhat secretive, and their smooth, shiny bodies can make them look almost like a strange cross between a lizard and a snake.
They are completely harmless to people, however, and are fascinating little predators in their own right.
What exactly is a skink?
Skinks are lizards belonging to the family Scincidae. They occur across much of the world's warmer regions and are an incredibly diverse group.
One of their most recognizable characteristics is their elongated body and relatively short legs. Some species have such tiny limbs that, when they disappear through grass or leaf litter, they can momentarily look more like snakes than lizards.
Panama has native skinks belonging to the group commonly known as the mabuyine skinks, including species in the genus Marisora. Taxonomy in this group has changed considerably over the years, which explains why an older field guide may give a skink in Panama a completely different scientific name from a modern source.
That taxonomic confusion is actually part of what makes these animals so interesting.
The Central American mabuya
One of the skinks found in Panama is the Central American mabuya, Marisora unimarginata.
It occurs in Panama as well as Costa Rica and Nicaragua, and is currently considered a valid species.
Another species in the region is Marisora brachypoda, commonly referred to as the Western Middle America skink or mabuya centroamericana in Spanish.
The word mabuya can be confusing because older scientific literature used Mabuya for many New World skinks that are now divided among several different genera. A major taxonomic revision using morphology and DNA reorganized these lizards into numerous genera, including Marisora.
So if you encounter an old article calling a Panamanian skink Mabuya, that doesn't necessarily mean the information is wrong. It may simply reflect the scientific classification used at the time.
They look remarkably smooth
Skinks often have a distinctive appearance.
Their scales are relatively smooth and shiny compared with many other lizards, giving them an almost polished appearance. Their bodies are elongated, their tails are usually long and their legs are comparatively short.
When one suddenly darts across a trail, it can be easy to mistake it for a small snake.
Then you notice the legs.
The resemblance to snakes isn't accidental. Skinks have evolved body shapes that allow them to move efficiently through vegetation, leaf litter and narrow spaces.
Their elongated bodies can be particularly useful when they are hunting through dense vegetation.
Fast little predators
Despite their small size, skinks are active predators.
They feed on small invertebrates such as insects and other tiny creatures. A skink moving through a garden or forest floor is effectively searching for miniature prey that most people would never notice.
This makes them useful members of Panama's ecosystem.
A garden containing skinks can have its own little predator community operating almost invisibly among the leaves and rocks.
An insect lands.
The skink freezes.
It watches.
Then, almost unbelievably quickly, it darts forward.
The entire event can be over before a person has even realized what happened.
Where might you see one?
Skinks can be encountered in a variety of environments, although particular species have their own habitat preferences.
They can occur around vegetation, forest edges, gardens and areas where there is plenty of leaf litter and cover.
The important thing for anyone hoping to see one is to look down.
Visitors to Panama often spend their time looking upward for monkeys and birds. Others scan the trees looking for sloths or snakes.
Skinks are usually much closer to the ground.
A warm rock, fallen branch, pile of leaves or sunny patch beside a trail can be worth watching.
Panama's rainforest isn't their only home
One of the interesting things about skinks is that you don't necessarily need to enter pristine rainforest to encounter one.
Panama's mosaic of forests, farms, gardens, rural properties and developed areas creates countless small habitats.
This is especially relevant in places where vegetation is dense but people are still nearby.
A skink may be living in exactly the sort of environment that a visitor considers "just a garden."
That makes them one of the reptiles that can quietly become part of everyday life in tropical Panama.
They are not dangerous
If you see a skink, there is no reason to be frightened.
They aren't venomous.
They aren't dangerous to people.
They aren't aggressive.
Their greatest defense is usually to run away incredibly fast.
Trying to catch one is generally a frustrating exercise because they can disappear into vegetation almost instantly.
For this reason, skinks are much easier to observe when you simply sit quietly and allow them to go about their business.
The incredible diversity of skinks
One reason the group is so fascinating is that "skink" describes an enormous range of animals.
There are skinks with tiny legs, skinks with relatively substantial legs, burrowing skinks, tree dwelling skinks and species that have evolved in remarkably isolated environments.
The family Scincidae is one of the major groups of lizards, and the evolutionary history of New World skinks is particularly interesting.
Researchers have discovered that the American mabuyine skinks represent a complex evolutionary radiation. A major study concluded that their ancestors colonized the Americas millions of years ago and subsequently diversified into numerous lineages.
That means the little skink disappearing beneath a leaf in Panama belongs to a much larger evolutionary story stretching across tropical America.
Panama has attracted serious skink research
Panama has also been important for scientific research into skinks.
In 1991, herpetologists Charles Myers and Maureen Donnelly published a detailed work specifically examining the lizard genus Sphenomorphus in Panama, including the description of a new species.
This is a reminder that Panama's reptile diversity is still much more complicated than what a casual visitor sees.
The country's enormous variety of elevations and habitats, from Caribbean lowlands to Pacific forests and high mountain environments, provides opportunities for closely related reptiles to evolve into different forms.
The mystery of their reproduction
New World mabuyine skinks are particularly interesting because of their reproductive biology.
Some members of this group have evolved live birth, rather than laying eggs.
Their reproductive adaptations are unusually sophisticated for lizards. Scientific research into the group has even highlighted remarkable similarities between their reproductive systems and some aspects of placental reproduction in mammals.
This is one of those facts that makes skinks considerably more interesting than their rather ordinary appearance suggests.
They may look like small shiny lizards scurrying through the garden, but their evolutionary history contains some extraordinary adaptations.
Why you might notice them more during the day
Like many reptiles, skinks depend on their surroundings for heat.
A sunny morning can therefore be a good time to look for them.
A skink may emerge from cover, warm itself and then become increasingly active as the temperature rises.
This can create a familiar tropical scene: birds are calling from the trees, insects are moving through the vegetation and a tiny skink is racing between patches of sunlight at ground level.
The animal may only be visible for a few seconds.
Then it is gone.
Don't confuse them with geckos or anoles
Panama has so many small lizards that it is easy to lump them all together.
But skinks have some useful identifying characteristics.
Geckos often have large eyes, soft looking bodies and specialized toe pads that allow many species to climb smooth surfaces.
Anoles tend to have longer legs and are often seen climbing vegetation, walls or tree trunks. Some males also display colorful throat fans called dewlaps.
Skinks generally have smoother, shinier scales, longer bodies and shorter legs.
Once you've seen a few, the difference becomes much easier to recognize.
A tiny predator hiding in plain sight
Perhaps the most enjoyable thing about skinks is how easy they are to overlook.
Panama has animals that demand attention.
A howler monkey announces itself from half a kilometre away.
A toucan can be impossible to miss.
A sloth can attract an entire group of tourists.
A skink does none of this.
It simply exists.
It hunts.
It warms itself in the sun.
It disappears under a leaf.
And it continues doing exactly what it has been doing long before people started walking Panama's trails.
For travelers who slow down and start paying attention to the smaller creatures, skinks can become one of the most rewarding discoveries.
The next time something shiny and strangely snake like suddenly shoots across a trail in Panama, take a second look.
It might just be one of the country's wonderfully overlooked skinks.