Finding these frogs sometimes requires considerable trekking; pursuing strange new calls, to seek out new frogs in new forests; boldly going where no herpetologist has gone before.
— Vences et al. 2024
At the right time of year along rushing streams in the humid rainforests that stretch the length of Madagascar’s eastern and northern mountain ridges, otherworldly trills of piercing whistles can be heard.
Are they birds? Insects? Communicator beeps? Tricorder noises?
No, they’re little treefrogs. Although they may seem at first glance to just be brown frogs, they are in reality dappled with little spots, sometimes bedecked with little X-like markings on the back, or a lichen-like patch, gloved with yellowish fingers—and their eyes striking, with a flash of blue at the outer iris, beside a strong black ring that surrounds the golden inner iris that is cracked with black filigree. Some even have shocks of bright red in the upper and lower iris.
Between calls, they clamber about amongst the thin twigs, leaves, and stems of bushes and trees. In the rushing water, their tadpoles use expanded sucking mouthparts to hold onto the rocks.
Until recently, all of these frogs were thought to be one widespread species, Boophis marojezensis, described in 1994. Genetics in the early 2000s and 2010s showed that there were several species here, not just one.
Now my colleagues and I have shown that they are in fact eight separate species, each with unique calls!
In reference to the bizarre calls that these little frogs make, we have named the seven new species after seven of Star Trek’s most iconic captains: Kirk, Picard, Janeway, Sisko, Archer, Burnham, and Pike!
Their descriptions are published Open Access in the journal Vertebrate Zoology.
On a personal note, this marks a big milestone for me, as it means I have now described over 100 frog species! I am very pleased that the 100th is Captain Janeway’s Bright-eyed Frog, Boophis janewayae (if you count them in order of appearance in the paper)—she is probably my favourite captain, and I really love Star Trek: Voyager.
Beyond the beeps
For the most part, I think Star Trek is an aspirational franchise; a vision of a future with a united human race (and other species/races beside, as part of the United Federation of Planets) seeking to explore the universe and understand their place in it. At a time when SciFi on television was getting its start, often with a heavily military/navy undertones (or overtones), Star Trek (The Original Series) put a scientist, Mr Spock, front and centre on its bridge crew.
Much of Star Trek is about discovery (one of the core functions of Star Fleet), and it often features interactions with nature and wildlife, in the broadest terms. While these portrayals in many cases are less than stellar (or downright problematic in some cases) from a modern perspective, they nonetheless highlight the centrality of curiosity, discovery, and a desire to protect nature as a central tenant of this vision of our future as humans.
This aspect of Star Trek is another to which we wish to pay homage with the description of these seven new species.
Plus, finding these frogs often requires quite a Trek…
Discovery
I had the good fortune to be involved in the discovery and collection of material for four of these species: Boophis siskoi and B. pikei from the Bealanana district in northern Madagascar in 2015–2016; and B. burnhamae and B. pikei from Marojejy in northeastern Madagascar in 2016. Like all such discoveries, each is its own story—each an episode, or several.
The discovery of Captain Archer’s bright-eyed frog, Boophis archeri, stands out in my memory. As Expedition Angano wrapped up, I took a splinter team consisting of myself, Marius Rakotondratsima, two local guides, and our driver, Davy, to forests at the southern edge of the Bealanana district, near the village of Ampandrana. Here, you cross a ridge and begin to descend towards the lowlands on the drive towards Antsohihy and beyond.
Beyond the ridge, the hills are almost entirely barren, but a few tiny patches of riparian forest hold on.
We made camp along a stream not far from the road, and spent the following days surveying these tiny forest patches for frogs and reptiles.
Already on the first night beside this stream, we could hear these tiny frogs emitting their piercing calls from the tiny strips of riparian forest along the stream.
It is one thing to hear these frogs, and another thing altogether to catch one; they sit high in trees, and jump about as they emit intermittent peeps, interrupted occasionally by their shrill whistles (in this case, a rather slow series). But, eventually, we did manage to catch one male. A few days later, I caught a second male at another site. And then finally, on the last day before we had to leave, I got very lucky: I found a female full of eggs.
Finding females is much harder than finding males, because they don’t call, and so don’t give themselves away. But having an egg-laden female like this is excellent, because it proves that she was reproductively mature.
I knew at the time that the specimens I was collecting belonged to the Boophis marojezensis species complex, which we have known since at least 2009 consists of multiple species. But I did not realise that this one was totally new.
And that was it. In all, Boophis archeri is known from just these three specimens; to my knowledge, nobody else has collected this species.
Meanwhile, the forests it lives in are disappearing, mostly in flames; compare these Google Earth images from 2015 and 2023, and you can see how nearby forests have been devastated in the interceding eight years:
Already in 2016, the local guides stopped us from melting our boots by walking around actively burning charcoal pits, and we found planks of wood harvested from these forests for local building projects.
But I remain hopeful. There is a decent chance that this species persists across the network of diminishing riparian forests that reticulate through the valleys across the area. Its existence in these tiny strips of forest means that it may be amongst the last species to go; other species that would penetrate further into the forest, may already be lost. In 2016, these forests had an astonishing diversity of reptiles and amphibians, considering just how small they were. It remains to be seen how long such populations can hold on, and how this kind of fragmentation affects their ability to maintain healthy levels of gene flow and diversity.
We hope that by dedicating these species to Star Trek captains, we can also bring more attention to their plight, to help support conservation efforts directed not just to them, but to the landscapes of which they are an integral part. Only by protecting the forests and landscapes, can we hope that their inhabitants can live long, and prosper.
The full citation:
Vences, M., Köhler, J., Hutter, C.R., Preick, M., Petzold, A., Rakotoarison, A., Ratsoavina, F.M., Glaw, F. & Scherz, M.D. (2024) Communicator whistles: a Trek through the taxonomy of the Boophis marojezensis complex reveals seven new, morphologically cryptic treefrogs from Madagascar (Amphibia: Anura: Mantellidae). Vertebrate Zoology 74:643–681. DOI: 10.3897/vz.74.e121110