Cruziohyla calcarifer – closing the circle

Over three years have passed since my unforgettable encounter with the fringe tree frog, Cruziohyla craspedopus, in the Amazon rainforest of Ecuador. That experience is still one of my all-time favorite moments of working in the field. Since then, I learned a lot about this species and nowadays I see them every time I visit Ecuador (as you can probably tell by their growing presence in my frogs gallery). Still, even after all this time the fringe tree frog remains high up on my list of the world’s most beautiful tree frogs. But it felt like something was missing. I decided to take a trip to Costa Rica, and right from the start I had one goal in mind: to find the other half of genus Cruziohyla – the splendid leaf frog, Cruziohyla calcarifer.

Splendid leaf frog (Cruziohyla calcarifer). Limón Province, Costa Rica

Splendid leaf frog (Cruziohyla calcarifer)

After researching a little on C. calcarifer’s distribution, I decided to contact the place that in my mind packed the best potential of seeing one. The Costa Rican Amphibian Research Center (neatly abbreviated C.R.A.R.C.!) is a small biological research station located close to the Siquirres River in the Guayacán rainforest reserve, in Limón Province. It is owned and run by Brian Kubicki, a conservation naturalist who dedicated his life to the study of Costa Rican amphibians, with special focus on glass frogs, poison frogs, tree frogs and lungless salamanders. I thought if there is one person that can help me find C. calcarifer in Costa Rica, it must be him. Remember the frog poster from 2003 that I mentioned in the beginning of my post about C. craspedopus? Brian Kubicki was the person signed at the bottom of that poster. Now how cool is that.

To begin with, the C.R.A.R.C. Guayacán reserve is stunning. There are many interesting corners with different types of microhabitats, so a huge potential for finding interesting reptiles and amphibians, not to mention arthropods. Unfortunately for me, I arrived to the reserve during a dry spell, as it has not rained for days prior my arrival, and most habitats that were not directly connected to natural springs or the river were fairly dry. Even so, I still found the place highly biodiveresed, and recorded many interesting species of arthropods, some of which I have not yet had the chance to see in the wild.

Alas, I was there to find C. calcarifer, and I was worried that the area might have been too dry. Brain kindly offered to hike with me at night and show me some good spots to find specific amphibians. And it did not take him long; once we hit a certain trail he found C. calcarifer within minutes! What a gorgeous species. I will just paste here my description of C. calcarifer from the post about its sister species:

“…a massive tree frog, with eye-catching coloration: dark green (dorsal) and bright orange (ventral). The sides of its body are finely striped in black against an orange background. Its eyes, featuring a vertical pupil – an indication this animal has a nocturnal lifestyle, are orange with a grey center. In addition, the foot-webbing is wide and the adhesion discs on the fingers are large and round, giving it a cutesy appearance.”

Splendid leaf frog (Cruziohyla calcarifer). Limón Province, Costa Rica

Isn’t it gorgeous? It is hard not to fall in love with these tree frogs.

This tree frog species is indeed, as its common name suggests, splendid. It was exactly what I expected. The frog we found was a female, and I was surprised how robust it was. It is not every day you get to see an amphibian that is both colorful and big.

Splendid leaf frog (Cruziohyla calcarifer). Limón Province, Costa Rica

Cruziohyla calcarifer. So adorable and quite a hefty frog

As mentioned, we found the frog at night. However, I wanted to see if I can locate it myself so I went back to the same spot in the morning. Let me tell you, it was not easy to find it in daylight. Not only it is difficult to find a green frog in the “sea of green” which is the rainforest, but also the tree frog is hunkered down and blends perfectly with the leaf it is resting on. After some time searching I thought about giving up, but then I looked up. I saw the perfect silhouette of a resting frog on one of the palm leaves, backlit by the sunrays penetrating the rainforest canopy. This could have still been an optical illusion created by a fallen leaf casting the silhouette. Yet, it was indeed C. calcarifer. I couldn’t be happier.

Splendid leaf frog (Cruziohyla calcarifer). Limón Province, Costa Rica

Splendid leaf frog (Cruziohyla calcarifer) in its rainforest habitat

Splendid leaf frog (Cruziohyla calcarifer). Limón Province, Costa Rica

Cruziohyla calcarifer is a good climber and spends most of its time in the canopy

Splendid leaf frog (Cruziohyla calcarifer). Limón Province, Costa Rica

Splendid leaf frog (Cruziohyla calcarifer) showing off its beautiful stripy coloration

To me, seeing Cruziohyla calcarifer in the wild is a way to close a circle on a journey that started over a decade ago in a backpacker’s hostel in Costa Rica, continued in the Amazon rainforests of Ecuador, and ended in Costa Rica again.

Splendid leaf frog (Cruziohyla calcarifer) and Fringe tree frog (Cruziohyla craspedopus)

Splendid leaf frog (Cruziohyla calcarifer) and fringe tree frog (Cruziohyla craspedopus). I wish moments like this one were possible in real life. Unfortunately, such a gathering of the two species is impossible. Even though both Cruziohyla species occur in Ecuador, they are separated by the Andes Mountains. C. calcarifer occupies the northwestern slopes, while C. craspedopus is found in Amazonian lowlands on the eastern side.

4 thoughts on “Cruziohyla calcarifer – closing the circle

    • Thank you! There is almost something cartoonish about Cruziohyla. It is a mesmerizing experience to see both species in the flesh, in their natural habitat. I feel very fortunate.

  1. Hello Gil, Great post and absolutely incredible images!!! Your photos are nothing short of spectacular, but I was especially blown away with the last image in the series above that were taken in the daylight. This image is by far the best photo of C. calcarifer I have ever seen. Adding to the beauty of the image is the fact that you went out on your own and found that individual during the day, not an easy task by any means, congratulations!!!! I very much enjoyed your visit to my reserve and having the opportunity to spend some time with you in the field. Thank you for sharing your great knowledge of invertebrates, I do hope that you are able to visit again in the future! Best regards, Brian

    • Hi Brian, thanks so much for your kind words! They mean a lot to me.
      It was well worth it to spend the time looking for and then photographing C. calcarifer. Definitely one of my best experiences in Central America (it also involved an army ant raid while I was photographing. That was fun). I do have plans to return to the reserve, I hope I can do it soon!


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