A female Costa Rican Tropical Night Lizard photographed in La Fortuna. This is a very cool lizard that is endemic to Costa Rica and Panama.
You may wonder how you can tell that this is a female. You can tell that this is a female because all known Costa Rican Tropical Night Lizards are female, there are no known males. This is one of the very few vertebrates that reproduces parthenogenetically.
Parthenogenesis occurs when a population can reproduce without requiring a fertilized egg. This leads to a unisexual population because males are no longer necessary for reproduction. Some may be thinking that this sounds like a pretty good system, there are cons though. Without sexual reproduction heterozygosity becomes low. This isn't a problem in a constant environment, but in a changing environment (which is most environments) the heterozygosity that results from sexual reproduction becomes a huge advantage.
I saw two of these lizards while in La Fortuna, both at night of course. The first was on the side of a tree overhanging a large drop, so I couldn't quite get the angle I was hoping for (second picture). The second individual let me get three shots off before scurrying into some tree roots. You may notice in the second photo the she is missing her front left foot.