10/09/2026
Harper and I were out on a night walk together and came across this Basilisk hanging out in a cacao tree. Here's a little about him from Harper's perspective.
The Common Basilisk is found throughout Costa Rica, Panama, northern Colombia, and western Venezuela where it is common in a wide variety of ecosystems. It is most often encountered along riverbanks and streamsides where it forages for food during the day. It is famous for its ability to run on water when escaping predators, which is why it is also sometimes known as the Jesus Christ Lizard. Adults do not typically run more than 5 meters on water due to their large size and weight while juveniles have been documented running as far as 20 meters on water. There are a couple of notable features that aid them in doing so: their extended and compressed fingers as well as their long tail. The scales on their fingers also complement their compressed shape since they are fringed, adding extra surface area to each digit.
Adult males like this one are well known for their large sails and brighter colors (relative to the females and juveniles). While the dorsal and caudal crests look like they may play a role in this species' semiaquatic behavior, there is actually little to no association between the two. The leading hypothesis that has been proposed to explain the purpose of these crests revolves around sexual selection. There is evidence to suggest that larger crests are more attractive to females. The role of sexual selection also helps to explain why females and juveniles do not possess these striking sails. The closest relatives of the basilisks are the casquehead iguanas and the helmeted iguanas; as their name suggests, they also have modified skulls like this common basilisk, as this feature is considered to be a defining characteristic of the family they collectively belong to.