The Yellow Treefrogsgenus Dendropsophus

Hourglass Treefrog (D. ebraccatus)

Yellow Treefrog (D. microcephalus)

San Carlos Treefrog (D. phlebodes)

 

 

From the lowlands of tropical Mexico down into most of tropical South America, there is a large genus of small treefrogs in the genus Dendropsophus.  While some members of this genus are boldly marked with white patterns, the Central American species are generally small yellow treefrogs with some brown pattern of blotches or reticulations.  They can look superficially similar.

 

The three species in Central America are:

• Dendropsophus ebraccatus (Hourglass Treefrog)
• Dendropsophus microcephalus (Yellow Treefrog)
• Dendropsophus phlebodes (San Carlos Treefrog) 

Not only do these species look a bit similar, but their calls can be reminiscent of each other as well.  The Hourglass Treefrog (D. ebraccatus) is the easiest to distinguish. Not only is its small yellow body boldly marked with large "hourglass" shaped brown blotches, but its call is also slightly different than its congeners.  The call of D. ebraccatus is a coarse, loud "creek" or "creek-it"  It is more course than the other two species and tends to be a single, or at most, a double note..

Dendropsophus ebraccatus calls from Gamboa, Panama

 

The Yellow Treefrog (aka Small Yellow Treefrog - Dendropsophus microcephalus) lacks the bold blotches of D. ebraccatus and is mostly a yellow frog with some brown speckling or net-like reticulations on its back. This is a frog of forest clearings, marshes and grasslands. The call of D. microcephalus is also described as a "creek", but the call has multiple parts strung together as a "creek-cree-cree-creek". It has a slightly higher pitch/frequency than D. ebraccatus as well.

Dendropsophus microcephalus calls from the grasslands south of Pacora, Panama.

Here is a recording of Dendropsophus ebraccatus and D. microcephalus calling together. You can hear how the D. microcephalus calls are higher in frequency (pitch) and have a series of repeats after each call.  The ray gun "p-tew" calls are the Tungara Frog (Engystomps pustulosus).

Dendropsophus ebraccatus and D. microcephalus together

 

The problem species for me are the two less marked species, D. microcephalus and D. phlebodes. In the northern parts of the range in tropical Mexico and northern Central America, you only find D. microcephalus.  However in Costa Rica and south , you can find both species.  In Costa Rica, D. microcephalus tends to be found on the Pacific side and D. phlebodes on the Atlantic side, but in Panama and further south, the species appear to be sympatric.  

By appearance, Dendropsophus phlebodes can apparently be distinguished by having a pair of parallel brown stripes on the upper back and neck.  Dendropsophus microcephalus generally lacks those stripes.  While D. phlebodes is a frog of tropical forest ponds and D. microcephalus is a coastal/marshy grassland species, both species can occur in grassy, disturbed areas.  They are believed to be closely related, much more closely related than either species is to D. ebraccatus (Orrico, et al 2020).

And normally on my page, this is where I would tell you the way to tell them apart is to compare their calls.  But to my ear, the calls sound very similar.   Both species make a "creek-creek-crk-crk-crk" type call with a strong started "creek" followed by a fading series of shorter notes. 

 

Dendropsophus phlebodes calls from the a forest pond in Sarapiqui, Costa Rica.

And here's D. microcephalus again for comparison...

Dendropsophus microcephalus calls from the grasslands south of Pacora, Panama.

Can you hear a clear difference between them? D. microcephalus calls seem to be a bit higher in frequency, but the rhythm seems to be the same.   I have a tough time telling them apart.  

Here's a short recording comparing the latter part of the call of these species (the "crk-crk-crk" parts).   First you hear three "crks" by D. phlebodes followed by three from D. microcephalus..

Looking at the spectrograms of those two recordings, the carrier frequency for D. phlebodes seems to be around 3600-3700 Hz while that for D. microcephalus seems to be around 5500-6000 Hz.   Is that consistent?  I don't know, but it looks like I will need to dive deeper.  And could you "hear" that difference on a rainy night next to a pond in a mosquito infested flooded pasture?  I really don't know.   Hopefully I'll get some chances to get some more recordings of both species.

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© Chris Harrison 2025

Victor G.D. Orrico, Taran Grant, Julian Faivovich, Mauricio Rivera-Correa, Marco A. Rada, Mariana L. Lyra, Carla S. Cassini, Paula H. Valdujo, Walter E. Schargel, Denis J. Machado, Ward C. Wheeler, Cesar Barrio-Amorós, Daniel Loebmann, Jiří Moravec, Juliana Zina, Mirco Solé, Marcelo J. Sturaro, Pedro L.V. Peloso, Pablo Suarez, Célio F.B. Haddad The phylogeny of Dendropsophini (Anura: Hylidae: Hylinae) https://doi.org/10.1111/cla.12429