First frogs of the year

I am back in Costa Rica to work for another two months as a naturalist guide. It's always great to be here and admire the rich biodiversity. The night hikes are mainly focused on frogs... so here are a couple of the first species I found. Beginning with the most famous one: Red-eyed Tree Frog (Agalychnis callidryas).

Agalychnis callidryas - Red-eyed Tree Frog

This tiny juvenile Dwarf Glass Frog (Teratohyla spinosa) measures around 1 cm (0.39 in). Finding this adorable frog in the rainforest was like finding a needle in a haystack. A very common, still beautiful species is the Masked Tree Frog (Smilisca phaeota). I found one posing nicely on a vine. Another really cool sighting of the first tours was a Reticulated Glass Frog (Hyalinobatrachium valerioi).

 

Teratohyla spinosa - Dwarf Glass Frog

Smilisca phaeota - Masked Tree Frog

Hyalinobatrachium valerioi - Reticulated Glass Frog

Frog Kindergarten

Shortly after its metamorphosis, the Noble's Robber Frog (Craugastor noblei) has quite different proportions than adult specimens. The head looks way too big for the small body.

The Red-eyed Treefrog (Agalychnis callidryas) will have much more intense colors when fully grown. 

This Green-and-black Poison Dart Frog (Dendrobates auratus) already has its beautiful colors, but still the cute baby face.

Maybe it is the first night out of the water for this tiny Masked Treefrog (Smilisca phaeota). Recently it used to swim in the pond as a tadpole.

I also want to present a young Leaf Litter Toad (Rhaebo haematiticus). Because of their size (about 2 cm) and camouflage it is easy to overlook.

Happy Valentine's Day!

I would not call myself a romantic guy and I've never paid much attention to Valentine's Day. In addition, the distance to my girlfriend is currently almost 10.000 km. So there is no fancy dinner, candlelight, and... you know what. Nevertheless, I would like to seize the opportunity to show some happy couples. Frog couples.

Smilisca phaeota is a relatively large frog with adult size reaching up to 78 mm (3.1 in). The dark brown patch that starts at the tip of the snout and continues through the eye and the eardrum, along the frog's face, is the reason for their common name: Masked Tree Frog.

This rarely seen Spiny Glass Frog (Teratohyla spinosa) messures only about 2 cm (0.8 in). It is found in Colombia, Costa Rica, Ecuador, Honduras, Nicaragua and Panama.

In most frog species the males are smaller than the females, because when they mate the female carries the male on its back. This is called Amplexus (Latin "embrace"). The sexual dimorphism is particularly evident in this pair of Chiriqui Robber Frog (Pristimantis cruentus). Remarkable how small the male is in relation to the female

To conclude, I want to show you a cool observation of Red-eyed Tree Frogs (Agalychnis callidryas). The female attaches a clutch of eggs to the underside of a leaf and the male is about to fertilize them.


www.amphibiaweb.org
Leenders, T. 2001 A Guide to Amphibians and Reptiles of Costa Rica Zona Tropical
Savage, J. 2002 The Amphibians and Reptiles of Costa Rica

New nocturnal neighbors

Since January I am working (volunteering) for Callidryas Tours and Arenal Oasis as a tour guide. At the Arenal Oasis Eco Lodge I saw numerous animals, especially during the night hikes. Here I want to share some of those with you.

This cute Powdered Glass Frog (Teratohyla pulverata) messures barely a length of 3 cm (1.2 in) max. Due to their small size and good camouflage, they are hard to find.

I found this juvenile Blunthead Tree Snake (Imantodes cenchoa) coiled up on the leaf of a bromelia. These snakes feed mainly on frogs and lizards.

Shiny green Rhinoceros Katydid (Copiphora cultricornis) nymph.

The Pygmy Rain Frog (Pristimantis ridens) is very common in this area. Growing to 2.5 cm (0.98 in), this is another very small species.

Quite rare to see: Striated Webfoot Salamander (Bolitoglossa striatula). This species occurs in Honduras, Nicaragua and Costa Rica. 

This big ant is 3 cm (1.2 in) long and feared by man. The sting of this species is considered to be the most painful sting of the entire insect kingdom. It's described to be as painful as a gunshot. That's why this ant is called Bullet Ant (Paraponera clavata).

The Red-eyed Treefrog (Agalychnis callidryas) should be part of every night hike in Costa Rica...

Beautiful coloration on this juvenile Eyelash Viper (Bothriechis schlegelii). They are ambush predators, so they can remain motionless for hours.

And thus the circle closes, I finish this report as I started it: with a member of the amphibian family called Centrolenidae. This one is an Emerald Glass Frog (Espadarana prosoblepon).

Nocturnal neighbors

At night you can see many animals right next to our station. Especially when it rains, there is a lot of "traffic" around our ponds. I took the following pictures within a 5 minute walking distance to my room.
Still at the building this Turnip-tail Gecko (Thecadactylus rapicauda) was looking for food. With approx. (12cm, 4.7 in) it is the biggest Gecko of Costa Rica.

The Northern Cat-eyed Snake (Leptodeira septentrionalis) is abundant near the ponds here.

As well as the Hourglass Treefrog (Dendropsophus ebraccatus) and the famous Red-eyed Treefrog (Agalychnis callidryas)

I also saw some Plain Blunt-headed Tree Snakes (Imantodes inornatus).