The stinkin' Tink Frogs (Diasporus)The saga continues!

Common Tink Frog (D. diastema) trying to impress a female that has approached his leaf.
Near Aguas Zarcas, Costa Rica.

Tink Frogs in the genus Diasporus are named for their metallic "tink" calls.

The problem I have is as follows:

This is the widespread Common Tink Frog (Diasporus diastema) for which the species gets its name. This was recorded in north-central Costa Rica.  Anyone in the area will confirm this as a "Common Tink Frog".  Notice it is more of a dry "tick" than a metallic "tink".

Compare that tink to this more metallic sound that I recorded in southern Costa Rica.  Again, people in the area will tell you this is the Common Tink Frog.

Both of these recordings are consistently identified as Diasporus diastema by iNat identifiers.

But is it really the same species? I'm not convinced.  I've listened to a LOT of frog calls over the years, and I think those two calls are coming from different species.

But wait, there's more.....

Here's another recording (from Panama this time) of some frogs that "people in the know" have identified as D. diastema on my recordings. Notice how the call is no longer a percussive "tick" or "tink" but now is a fast, upward, whistled call...

Now enter the confusion, the Yellow-dyer Tink Frog (Diasporus citrinobapheus). This species is very similar overall to the Common Tink Frog, but is a bit less "tuberculate" and has the odd character of staining your skin yellow when they are handled.

I know this preceding call was a Yellow-dyer Tink Frog because we caught the individual that was calling and it stained our skin yellow!

Yellow Dyer Tink Frog who had the upward whistled "tink"
Anton Valley, Panama

So now listen to this recording from Panama. If you listen carefully, you hear the upward whistled tink AND the more dry tick sound (in the background). The upward whistled calls sound like the Yellow-dyer, but a well-known expert on frogs from Central Panama told me that call is the Common Tink Frog, and the higher pitched tink is a different Diasporus species (they didn't ID it for me though).

Confused? So am I.

Either the dry tick, metallic tink and the upward whistled call are all made by the same species AND a related species makes the upward whistled call as well even though they overlap in range or....or these identifications are all wrong?

You might be inclined to suggest that the calls are identical and the way to learn to tell their calls apart is to catch them calling and identify them visually. The problem is many of these small frogs are very similar looking and difficult to ID even in hand. 

Also, it is very hard to find a calling tink frog because the short, sharp and sporadic tinks don't let your brain home in on the location of the caller very well. And they call from on top of leaves which has a sort of ventriloquist effect in the forest.

Then there is the hypothesis that both species (D. diastema and D. citrinobaphus) have overlaps in their calls and that D. diastema sometimes sound different, occasionally like the other species. After all, there is variation is species (Darwin, 1859)

But I have a more fundamental problem with this idea. Frog calls are a main mechanism of pre-zygotic reproductive isolation in frogs. They have to sound different than other species, at least to females of the same species. If the males are making two different calls that sound like the calls of other sympatric species, how would females be able to tell them apart?

I think the real answer is that many people, including experienced people, are misidentifying these tink frog calls because they do sound similar. Add to that the fact that many areas only have one "tink" frog so people just assume what they are hearing must be the Common Tink Frog (D. diastema), after all, it is what they commonly hear?

I may be wrong, and maybe I'm the only person who doesn't get how this upward whistled tink, the metallic tink and the drier, shorter tink can all be the same frog call that matches the call of other similar species that overlap in range/habitat?  If I'm wrong about this, I would love to be corrected, but I'm going to have to be able to hear the difference.

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Just to add to the fun, there are other frog genera that have tink-like calls and they can increase your confusion about the source of "tinks".

Here is the Lesser Antilles Robber Frog (Pristimantis urichi) recorded in Trinidad:

And then we have to consider that many of the glassfrogs (Centrolenidae) also have high pitched peep type calls that can sound similar at night in the field.

Here is Tatayo's Glassfrog (Hyalinobatrachium tatayoi) from Panama. It is noticeably higher pitched, but can be confusing at first....

And here's its cousin the Yellow-flecked Glassfrog (Sachatamia albomaculata), again from Panama.

And another, the Chiriqui Glassfrog (Teratohyla pulverata), this one from southern Costa Rica.

And these are just the species I have recordings of! There are dozens of other species in multiple genera that make this peeping sound.

So if you hear a tink in the night in Central America, you might be hearing a Tink Frog....or maybe not?

I guess I need to make another trip down to Panama/Costa Rica and record and chase down these individual calling frogs. I'm sure it is a journey I will have to make alone. I don't see anyone else being interested in making the trip down to Central America just to waste time on the most common, widespread frog species of these tropical forests ignoring all the other "cool" stuff. 🤣

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© Chris Harrison 2026