The second species definitely is Leptodactylus savage. The first one, I'm not sure :-)

Thank you very much for the confirmation!

Hello Gregor,

the second one is, like Andew said, from the genus Leptodactylus, I am rather sure that it is Leptodactylus pentadactylus.

The first belongs to the family of Hylidae, the huge finger disks show this, but I cannot tell you genus or species. It may be Smilisca sordida, but this is not more than a challenge. This species has a very extreme variation in colouration and its identification from a photo is very difficult to impossible.

Literature: W. Huber, A Weissenhofer: "The Amphibians and Reptiles of the Golfo Dulce Region Costa Rica"; Corcovado National Park, Piedras Blancas National Park, Regenwald der Österreicher; University of Vienna, Faculty Centre of Botany, Rennweg 14, A 1030 Vienna, Austria; [email protected] (M. Ringler)

Best,

Rudolf

Great, thanks a lot. I will try to follow your suggestions and contact the authors of the book you mentioned.

Regards

Greg

Here is the synthesis so far:

1. probably Smilisca sordida (Hylidae)

2. Leptodactylus pentadactylus (Leptodactylidae)

Hello Gregor, I´m Manuel Acevedo from Guatemala. I think the first species might belong to the genus Isthmohyla. Not sure if it could be Smilisca. The second one is Leptodactylus savagei;  Leptodactylus pentadactylus has a southern distribution (not in CR).  As I told you, my country is Guatemala, and my expertise in CR amphibians is poor.  You should contact Brian Kubiki (CR expert in Anurans). 

Hope to be of some help.

Thanks a lot, I have contacted already B. Kubicki hoping for definitive identification. I will keep you informed.

Thanks for this specification. And also for the confirmationof L. savagei.

Hello Gregor,

Leptodactylus savagei was separated from L. pentadactylus (by HEYER 2005) - I did not know this. I took my informations most from: G. HÖBEL: The amphibians and reptiles of the Golfo Dulce region; Stapfia 88, Kataloge der oberösterreichischen Landesmuseen Neue Serie 80(2008): 305-328.

"All five members of the genus Leptodactylus that occur in Costa Rica are found in the Golfo Dulce region. Superficially similar to ranid frogs, they can be distinguished from them by the complete lack of webbing between the toes. The range in size is from the relatively small L. melanotus (40 mm) to the large L. pentadactylus (185 mm). The latter species, which is also known as the South American bullfrog or "rana toro", can be found in nearly every lowland rainforest. It is usually first spotted thanks to the bright red reflection of their eyes in the beam of a flashlight..."

See also here:

http://research.amnh.org/vz/herpetology/amphibia/Amphibia/Anura/Leptodactylidae/Leptodactylinae/Leptodactylus/Leptodactylus-savagei

Regards,

Rudolf

Dear Rudolf,

Thank you very much for these additional detailed specifications. We used in the field some local amphibian booklets/guides from Costa Rica / Osa... and they mainly gave L. savagei - and some of them use both names as synonymes (savagei = pentadactylus). So, for our purposes (mainly conferences) it will be enough to say that the picture shows an individual from the L. pentadactylus group. We have found them (as described in your text fragment) very easily each night due to reflection of their eyes.

Hi Gregor,

Sorry for the late reply, the email you used is not my most recent one and hardly checked. I agree with L. savagei, which basically is the split-off and newly described northern form of L. pentadactylus.

For the second picture S. sordida seems to be not a too bad guess - night colouration, as they look strikingly different during the day, and can also be highly variable. This is mainly based on proportions and shape of the snout and estimated size (as far as this is possible from the leaf). However, I have no identification literature available right now, and one would probably need more information (location, time, call) or even the specimen at hand for a good identification. I am not an expert on the Costa Rican herpetofauna, and the booklet from 2004 is mainly based on the book of Savage - I am more familiar with the Guiana Shield and Northern Brazil.

Best

Max

Thank you very much. I know it is not easy with just one photography. And the diversity of amphibians in Costa Rica is very high. I have contacted some local specialists. In case I will have any new hints I will post it on RG.

Dear Gregor ,

what is the estimated size of the tree frog?