Texas Chirping Frogs - Revisited
Little chirpers in the genus Eleutherodactylus

 

Greenhouse Frog (Eleutherodactylus planirostris)
from Naples, Florida

OK, so I've made a comparison entry before for the "Texas" species in the genus Eleutherodactylus, the Rio Grande Chirping Frog (E. campi or E. cystignathoides, if you prefer 😜) and Cliff Chirping Frog (E. marnockii).  But there's a new chirper in town, the Greenhouse Frog (E. planirostris) and we need to figure out how to identify it as well.

The Greenhouse Frog is spreading through the state of Texas. It is most often transported as frogs or eggs in potted plants (thus the name "greenhouse").  It is originally from the Caribbean, but is well established in Florida and that is probably the source of their transport across the Gulf Coast and into Texas. In fact, this species has spread to China and Taiwan, Singapore, the Philippines, Guam, Hawaii and many places throughout Mexico and Central America.

The Rio Grande Chirping Frog is native to eastern Mexico and the tip of south Texas, but has also been spread north through transport of frogs and their eggs.  They have been expanding their range in Texas over the last 40+ years.   And their rate of spread can be quite quick.  I remember looking for herps in west Houston in the late 70s and early 80s.  I flipped a lot of trash but never saw these tiny frogs.  But when I went back to those same areas in the mid 1980s, Rio Grande Chirping Frogs were abundant in the exact same places.

The reason these small chirping frogs in the genus Eleutherodactylus have spread so quickly is that they are natural invaders.  Not only are they tiny and easy to move around, but they are quite comfortable living in forests, weedy brushy areas, suburban gardens or even potted plants.  

But their most powerful invasion trick may be the fact that they have direct development.  This means they have no aquatic tadpole stage and their eggs just hatch into tiny little froglets.  Therefore the females don't have to find a pond or stream to lay eggs, they can just bury them in the soil of the potted plant they live in.   So eggs and babies get transported easily, the new arrivals can breed in the buckets they were transported in,et voilà!, you have an introduced population of chirping frogs.  It is worth noting that they are not known to be parthenogenetic (like we see in Brahminy Blindsnakes), so they still require a male and female or fertile eggs to be transported to establish a new population.

Previously, these little invaders were pretty easy to ID based on the fact that most areas only had one species or the other.   So if you were in Florida, it was a Greenhouse Frog (E. planirostris).  If you were in Texas, it was a Rio Grande Chirper (E. campi).  But now these two invasives are starting to spread towards each other and overlap in range.  Suddenly, just finding a small "chirping frog" doesn't always allow you to name the species.

Telling these two introduced species apart visually can be tricky.  I should mention here that much of my attempt to explain how to distinguish these species is derived from my limited experience and a lot from Tom Lott's (2017) published explanations

In general, some Greenhouse Frogs look noticeably different than Rio Grande Chirpers, others do not.  Both species are small and variable in color.  They are usually some shade of brown or greenish brown with some darker brown/black marks or reticulations on their dorsum.   Some show yellowish or reddish patterns as well.

But the Greenhouse Frog seems the more variable.  Some Greenhouse Frogs are brown, some are greenish brown, some are reddish brown and some are brick red.  Like some other Caribbean Eleutherodactylus, Greenhouse Frogs also have a "striped morph" which has bold light stripes on the dorsolateral edge of the body.   Rio Grande Chirping Frogs don't seem to have this morph?  

Also notice the mid-dorsal line of tubercles seen in this photo.  That is often another clue you are dealing with a Greenhouse Frog. 

If your little chirping frog has stripes like this, it is probably a Greenhouse Frog.  Rio Grande Chirpers don't show this color pattern.   Photo of Greenhouse Frog by Eliot VanOtteren from this iNaturalist record and used under Creative Commons license conditions.

One oft-cited difference is the colored "triangle" on the top of the head between the eyes and nose in the Greenhouse Frog.  But the Rio Grande Chirper can often show this light triangle on the head, it is just not as pronounced or as contrasty as you see in Greenhouse Frogs.  When it occurs in Rio Grande Chirpers, it is usually not much different in color to the rest of the body, just a bit lighter.  In Greenhouse Frogs this triangle is noticeable different (usually much lighter) than the body color.  Again, this difference is subtle but consistent.

Although this Rio Grande Chirping Frog (Eleutherodactylus campi) has a light triangle on its head, the dark mask helps us tell it isn't a Greenhouse Frog.
Palmetto State Park, Texas

One factor that might help distinguish them in areas of overlap is the present of a presence of a darker "mask" along the edge of their head through the eye (along the canthal ridge).  The mask fades as you move down towards the mouth, so it almost looks like the top of the head is "shading" the side of the face.   Not all Rio Grande Chirpers show this as much as others, but it is not usually seen in Greenhouse Frogs.   Some Greenhouse Frogs show lots of dark spotting on the face and even a dark stripe, but this "shading" pattern is not usually seen.

 

The dark mask along the edge of this frog's head leads us to identify it as a Rio Grande Chirping Frog (E. campi)

Another character that is sometimes give to help with the ID is the nature of the dark bar between the eyes (at the posterior edge of the triangle).  In Greenhouse Frogs, this bar is usually quite thick and continuous.  In Rio Grade Chirpers, this "bar" is made of a series of dark spots and usually broken in places.

To my eye, Greenhouse Frogs are also more rugose generally.  While Rio Grande Chirpers can have small tubercle-like bumps on their bodies, their skin between those bumps is fairly smooth.  Greenhouse Frogs have more "warty" skin with many more tubercles uniformly across their back.  This is a really subtle difference and doesn't work all the time in differentiating them. 

Another character that can help is the presence of a dark chevron on the back between the forelimbs (on the frog's "shoulders").   This dark arrow points backwards and is seen on many Greenhouse Frogs, but not on Rio Grande Chirpers. 

Greenhouse Frogs seem to have a more narrow rostrum (more pointed nose) than Rio Grande Chirpers as well.

So, if you find a small Eleutherodactylus in its area of overlap that has no dark mask along the edge of its head and a prominent lighter triangle on its somewhat pointy head, it is likely to be a Greenhouse Frog.  Otherwise it might be a Rio Grande Chirper.....maybe? 

Here's a couple of good example frogs that look superficially similar: 

This photo by Peter May, used under Creative Commons License, shows the combination of charateristics which can be used to ID most Greenhouse Frogs.

 
This photo shows the combinations of characteristics which can be used to ID most Rio Grande Chirpers.

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So they can be easy to tell apart, or not.

But of course, my blog is supposed to be about frog calls.  So do their calls sound different?

Well, yes and no.  Both species make a chirp and a trill call.

Here's a group of Rio Grande Chirping Frogs calling.  You can hear a series of their chirps and their trills

  

And here's a group of Greenhouse Frogs from the Everglades in Florida.

  

Notice how much more complex the call of the Greenhouse Frog is. It is usually a double or even triple chirp ("ch-dip" or "chi-chi-dip") whereas the chirp of the Rio Grande Chirping Frog is a single "chip".  In musical terms, the Greenhouse Frog plays one or two grace notes before most chips, the Rio Grande Chirper doesn't.

So while the Rio Grande Chirping Frog will make more than one chirp in a row, they are more spaced out. Take a look at this comparison spectrogram showing a Rio Grande Chirper followed by a Greenhouse Frog. The gaps between the double chirps are two to three times longer in the Rio Grande Chirper.  Also the gaps between the chirp groups are shorter in the Greenhouse Frog (they are more "talkative").   You can see that the Rio Grande Chirper gets 5 chirps out in about 3 seconds, the Greenhouse Frog gets 11 chirps out in the same amount of time (actually it is two Greenhouse Frogs talking back and forth). 


Here is the recording of that spectrogram.  In the first five seconds you hear the chirps of the Rio Grande Chirper followed by the quick eleven chirps of the pair of Greenhouse Frogs.

 So If you can learn to listen for the frequent double chirps of the Greenhouse Frogs in the areas where they overlap, you should be able to learn to hear the differences.  You can't always identify one from a single chirp, but when they are calling repeatedly, they give themselves away.  In a mixed chorus of both species, it would be hard once again.

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I started this blog post comparison about 10 years ago and am just now getting around to finishing it.  This is obviously a complex comparison that I will have revisit in the future, but if I don't stop now, I might never finish. 😉 

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© Chris Harrison 2025 

Lott, Tom.  2017.  Distinguishing between the Greenhouse Frog (Eleutherodactylus planirostris) and the Rio Grande Chirping Frog (Eleutherodactylus cystignathoides) (Anura: Eleutherodactylidae).  Southwestern Center for Herpetological Research 7(4) pp. 69-75.  https://www.southwesternherp.com/wp-content/uploads/2023/03/2017-SWCHR-Bulletin-Vol-7-Issue-4.pdf

Updating the Australian Treefrogs
Family Pelodryadidae

Chlorohyla xanthomera, formerly of the genera Litoria and Ranoidea

In 2025, a new phylogeny and taxonomic structure was published for the Australian Treefrogs.  This new arrangement split what were a few genera up into 30+ genera.  The net effect for me was I "lost" two genera and gained ten new ones.  This means a lot of my frog blog entries are using outdated taxonomy.  

Getting this up to date is going to take some time, so I thought I would make myself a new lifelist, more as a "to do" list as anything else. 

So my recording lifelist is now at 142 species, in 56 genera, and 15 families.


Family Genus Species recorded
Bufonidae


Anaxyrus 9

Incilius 3

Rhinella 3



Hylidae


Acris 3

Agalychnis 4

Boana 4

Dendropsophus 3

Hyla 8

Pseudacris 6

Osteopilus 1

Scinax 4

Smilisca3

Tlalocohyla 1

Trachycephalus 1

Triprion 1



Pelodryadidae


Carichyla 1

Chlorohyla 2

Colleeneremia 2

Cyclorana 4

Drymomantis 1

Litoria3

Mahonabatrachus1

Mosleyia1

Pelodryas 1

Pengilleyia 2

Sandyrana 1



Microhylidae


Austrochaperina 2

Elaschistocleis 1

Hypopachus 1

Gastrophryne 2



Myobatrachidae


Crinia 2

Limnodynastes 1

Platyplectrum 1

Uperoleia 2



Craugastoridae


Craugastor 3

Pristimantis 2



Eleutherodactylidae


Diasporus 2

Eleutherodactylus 9



Centrolenidae


Espadarana 1

Hyalinobatrachium 4

Cochranella 1

Sachatamia 2

Teratohyla 2


Leptodactylidae


Leptodactylus 7

Engystomops 1

Pleurodema 1


Ranidae


Lithobates 9



Dendrobatidae


Colostethus 1

Oophaga 2

Silverstonia 1



Hemiphractidae


Flectonotus 1



Aromobatidae


Allobates 1

Mannophryne 2



Rhinophrynidae


Rhinophrynus 1



Scaphiopodidae


Scaphiopus 2

Spea 2

The Yellow Treefrogs
genus 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

Costa Rica 2025

Ghost Glass Frog (Sachatamia ilex)
near Siquirres, Costa Rica
   
 

I spent 7 days in Costa Rica this August.  Unlike previous trips to CR, this was a frog recording trip. My previous trips have all been birding trips where I got a chance to do a few minutes or recording along the way.  This trip was planned as a frog recording trip with a bit of butterfly watching/photography in the intervening waking hours.   

So for that reason, I recorded quite a few species of frogs (~22) including the following new ones (I will provide links to the new blog pages as I make them):

San Carlos Treefrog (Dendropsophus phlebodes)
Blue-sided Leaf Frog (Agalychnis annae)
Parachuting Red-eyed Leaf Frog (Agalychnis saltator)
Lemur Leaf Frog (Agalychnis lemur)
Mahogany Treefrog (Tlalocohyla loquax)
Dwarf Glassfrog (Teratohyla spinosa)
Ghost Glassfrog (Sachatamia ilex) 
 

I also heard another species calling, but missed out recording because my recorder seems to have glitched?   I have several recordings from that location, but 3 of them have no sound. ðŸ˜­ It was undoubtedly user error, but if I can salvage something I will be able to add a recording of 

Gliding Leaf Frog (Agalychnis spurrelli)

Of course, I ran across some old friends as well and was happy to record these species again!

Red-eyed Leaf Frog (Agalychnis callidryas) 
Boulenger's Snouted Treefrog (Scinax boulengeri)
Snouted Treefrog (Scinax elaeochora)
Hourglass Treefrog (Dendropsophus ebraccatus)
Yellow Treefrog (Dendropsophus microcephalus)
Northern Smokey Jungle Frog (Leptodactylus savagei)
Sabinal Frog (Leptodactylus melanonotus)
Mexican White-lipped Frog (Leptodactylus fragilis
Fleischmann's Glass Frog (Hyalinobatrachium fleischmanni)
Yellow-flecked Glass Frog (Sachatamia albomaculata)
Giant Toad (Rhinella horribilis)
Striped Rocketfrog (Allobates talamancae)
Strawberry Dart Frog (Oophaga pumilio)
Tink Frog (Diasporus diastema)

 

So my recording lifelist is now at 142 species, in 48 genera, and 15 families.


Family Genus Species recorded
Bufonidae


Anaxyrus 9

Incilius 3

Rhinella 3



Hylidae


Acris 3

Agalychnis 4  (maybe 5)

Boana 4

Dendropsophus 3

Hyla 8

Pseudacris 6

Osteopilus 1

Scinax 4

Smilisca3

Tlalocohyla 1

Trachycephalus 1

Triprion 1



Pelodryadidae*


Litoria 10

Nyctimystes 1

Ranoidea 8



Microhylidae


Austrochaperina 2

Elaschistocleis 1

Hypopachus 1

Gastrophryne 2



Myobatrachidae


Crinia 2

Limnodynastes 1

Platyplectrum 1

Uperoleia 2



Craugastoridae


Craugastor 3

Pristimantis 2



Eleutherodactylidae


Diasporus 2

Eleutherodactylus 9



Centrolenidae


Espadarana 1

Hyalinobatrachium 4

Cochranella 1

Sachatamia 2

Teratohyla 2


Leptodactylidae


Leptodactylus 7

Engystomops 1

Pleurodema 1


Ranidae


Lithobates 9



Dendrobatidae


Colostethus 1

Oophaga 2

Silverstonia 1



Hemiphractidae


Flectonotus 1



Aromobatidae


Allobates 1

Mannophryne 2



Rhinophrynidae


Rhinophrynus 1



Scaphiopodidae


Scaphiopus 2

Spea 2

 

* - I am aware of the massive 2025 revision of the Australian Pelodryadid frogs. There are a lot of new genera and reassignments of species. I will probably slowly have to incorporate these changes into my blog slowly when I get the time. It will involve a lot of name changes!  I guess the good news it I get a bunch of new genera on my lifelist?

Blue-sided Leaf Frog
Agalychnis annae

Blue-sided Leaf Frog (Agalychnis annae)
San Jose, Costa Rica

The Blue-sided Leaf Frog (Agalychnis annae) was the last new species I recorded in Costa Rica.  That's because I recorded it in the grounds of the hotel we were staying at in San Jose the night before we flew home.   The embarrassing thing was that the beautiful grounds of our hotel (Hotel Bougainvillia) had a couple of small ponds and one of the ponds had a sign talking about the "Golden-eyed Treefrog".  I figured it was a translation problem and they really were talking about the common and widespread Red-eyed Treefrog (A. callidryas).  

Blue-sided Leaf Frog range map from IUCN Redlist

On our last day in San Jose, as we walked around the grounds taking photos, I looked at the sign again and realized they were talking about a different species altogether, Agalychnis annae!  As we ate dinner I looked over my Costa Rican amphibian book and was shocked to discover that not only was A. annae a different species than I had originally thought, but it was almost extinct across much of its range and there were a few remnant pockets of this species found in gardens and parks in the sprawling, polluted, overcrowded metropolis of San Jose!

So my plans for that evening were originally just to get photos of the Peralta Frogs (Lithobates taylori) that lived in these garden pools, but now I had a new and much more exciting target....if only they would call!

Turns out they did call that night even though it hadn't rained that day.   We were able to find a number of these big green frogs hiding amongst the rushes and reeds surrounding the ponds.   They were quite shy, preferring to cling to the stems of the reeds/rushes rather than sitting up openly on top of leaves like the other Agalychnis species I had encountered.

The call of this frog is best described as a quiet "croak" or "puck" sound.   They were only calling very intermittently as heard in this recording. This frog only calls four times in the two minutes of this recording.  It calls at 4 seconds, 25 seconds, 66 seconds and 104 seconds in.  It takes a fair bit of patience to capture anything at all.   I assume they would call more aggressively during rains?

Here's another recording made of a different individual where the calls are a bit more frequent.


Blue-sided Leaf Frog calls

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© Chris Harrison 2025

Dwarf Glass Frog
Teratohyla spinosa

 

The Dwarf Glass Frog (Teratohyla spinosa), as the name implies, is a small Centrolenid frog found in lowlands and tropical foothills on the Atlantic versant of Costa Rica and Panama, then into eastern Panama and the foothills of western Colombia and Ecuador. There is apparently a disjunct population in eastern Honduras and there are recent records from Nicaragua..  The curious gaps in range in most of Nicaragua and central Panama may represent under-sampling or may be the indication of the disappearance of intervening populations?  This is one of the species that appears to be increasing in numbers again after a population decline in the last few decades associated with chytrid infections.

 

We found more than a dozen of this small frog calling from leaves along a rocky stream at the Costa Rican Amphibian Research Center.  Some  were calling many meters away from the edge of the stream.  The individual in the photo above was photographed and recorded calling from the leaf it is sitting on, a meter or so above the ground and around 5 meters away from the stream.

The call of this species is best described as a high-pitched, buzzy "creek-creek-creek" with a carrier (dominant) frequency around 5.5 to 7 kHz.   In the recordings I was able to capture, the call was a series of five creek sounds that descended in pitch towards the end.  I also noticed that the fourth creek was shorter than the others, almost a sort of grace note.  So the call could be transliterated as "creek-creek-creek-cre-creek".

Here is a spectogram of one of that series of calls.  You can see the "trilled" nature of the creeks, the shorter fourth creek, and how the frequency of the calls decreases at the end.

 


Dwarf Glassfrog calling

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© Chris Harrison 2025

Amphibiaweb Account for Teratohyla spinosa 

Ghost Glass Frog
Sachatamia ilex


Certainly one of the most striking frogs I was able to record in Costa Rica this year was the Ghost Glass Frog (Sachatamia ilex).  These amazing frogs are almost other-worldly in appearance.  Their slender green bodies, delicate limbs and amazing big white eyes with their "scribbled" iris pattern make this one of the most sought after target species to visitors  in its range.

This beautiful species occurs in the foothills of the Atlantic versant of Costa Rica then south into the Darién region of Panama and into the northwestern part of Colombia.  This is a frog of rocky streams in the steep rainforest valleys.   They are usually found on leaves or stems at night along those rocky streams. 

Interestingly, this is one of several species of frog that seemed to disappear from much of its range about 25 years ago due to chytrid fungal infections, but seems to have made a partial comeback. 

Sachatamia ilex range map from IUCN Redlist Database

We found several of these Ghost Glass Frogs along a rocky stream at the Costa Rican Amphibian Research Center in the evening after some heavy daytime rains.

Like many glass frogs (Centrolenidae), the call of this species is a high pitched single note in the 7-8kHz frequency range. To my ear, the call of the Ghost Glass Frog sounds like a high pitched "tsip". When we heard them, this single "tsip" was repeated every 4-5 seconds from the leaves where they sat and called.

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© Chris Harrison 2025

Parachuting Red-eyed Leaf Frog
Agalychnis saltator

 

The Parachuting Red-eyed Leaf Frog (Agalychnis saltator) is another bright green leaf frog from the tropical lowlands of the Atlantic versant of northeastern Costa Rica.  There are also disjunct populations in northern Nicaragua and eastern Honduras. This frog is similar looking to the Red-eyed Leaf Frog (A. callidryas) but lacks the light striping within the lateral blue side stripes

Agalychnis saltator range map from the IUCN Red Database

The curious name "Parachuting" Leaf Frog is a reference to their habit of leaping down from high in the tree canopy down onto lower leaves for reproduction.  As they drop, they spread their toes and use their widely webbed feet to slow their descent.

Males of this species call from leaves near or over water edges.   The individuals we found were calling from much higher leaves than the congeneric species of leaf frogs which share their breeding ponds.  A couple of males were calling 3 or 4 meters off the ground.

To my ear, the call of this species is a short dry "wreck" or "ruck" sound.   It has a carrier frequency around 2300 Hz, quite a bit lower than other Leaf Frogs.   Here is short recording of two A. saltator calling back and forth (with a couple of the higher "pip" of A. lemur towards the end) .

In this second recording, you hear more of what it sounded like with several other species calling with the A. saltator.

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© Chris Harrison 2025

Mahogany Treefrog
Tlalocohyla loquax

The Mahogany Treefrog (Tlalocohyla loquax) was kind of a white whale for me.  I have been herping and looking for frogs in its range many times over the last 40 years and although I've found a lot of other frog species in that range, I could never find or hear a Mahogany Treefrog!

Mahogany Treefrog range map from IUCN Redlist

Tlalocohyla loquax is not a rare frog, ranging from the lowlands of the northern isthmus of Tehuantepec (where I have herped), over most of the Yucatan platform (where I have traveled extensively), and down into Belize (where I failed to find them) and down into northern Costa Rica (where I also failed to find them). Other herper friends would often chuckle at my inability to find this relatively common species considering how much travel I had done within their range. 

Finally in August 2025, I was able to find my white whale!  While searching for frogs at the Costa Rican Amphibian Research Center, Brian led us to one of his ponds in the forest and we immediately heard the percussive calls of this species. We heard two of these frogs calling back and forth at this small pond, but because they were calling from a heavily vegetated area away from the edge, we couldn't see them. We came back to that pond on multiple occasions in the days we were there and still couldn't find them. Finally on our last visit, Tim was determined to find one of these frogs to show me and eventually his eagle eyes spotted one way back through the vegetation. I was able to snap the photo posted above.  My trip was complete - I had my white whale both in a photo and a recording!

To my ear, the call of this treefrog is percussive "deck" or "puck" often repeated as a double "de-deck".   In this recording you can hear a couple calling on the left side.  You also hear the "creek" calls of the Hourglass Treefrog (Dendropsophis ebraccatus)  with the nasal trill of the Olive Snouted-Treefrog (Scinax elaeochroa) and, of course, the metallic "tinks" of Tink Frogs in the background. 

In this second recording, you can hear how the notes become more complicated as the frogs start calling more often, producing a "de-de-deck" sort of call.

I found several much rarer species on our trip. But getting this frog onto the lifelist was still one of my anuran highlights of our trip!

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© Chris Harrison 2025

IUCN Redlist Database Entry for Mahogany Treefrog