Diamond Frog Discovered

New Species of Diamond Frog Discovered in Madagascar

German herpetologist Mark Scherz has discovered a new species of diamond frog living in northern Madagascar.

Rhombophryne ellae. Image credit: Mark Scherz.

The diamond frogs belong to Rhombophryne, a genus of microhylid frogs in the subfamily Cophylinae.

More than 20 species are currently recognized in the genus, all endemic to Madagascar.

Named Rhombophryne ellae, the newfound species is known only from the Montagne d’Ambre National Park.

“As soon as I saw this frog, I knew it was a new species,” said Dr. Scherz, a researcher at the Bavarian State Collection of Zoology, the Technical University of Braunschweig, and the University of Konstanz.

“The orange flash-markings on the legs and the large black spots on the hip made it immediately obvious to me.”

“During my Master’s and PhD research, I studied this genus and described several species, and there are no described species with such orange legs, and only few species have these black markings on the hip.”

“It’s rare that we find a frog and are immediately able to recognize that it is a new species without having to wait for the DNA sequence results to come back, so this was elating.”

Rhombophryne ellae is most closely related to a poorly-known and still undescribed species from Tsaratanana in northern Madagascar, but is otherwise quite different from other species in the genus.

With the orange coloration on its legs, it joins the growing list of frogs that have red to orange flash-markings.

The function of this striking coloration remains unknown, despite having evolved repeatedly in frogs, including numerous times in Madagascar’s narrow-mouthed frogs alone.

As Rhombophryne ellae is known from a single individual, its Red List status cannot be confidently estimated.

However, other microhylid frogs from the same area have been suggested to be Near Threatened due to their small range and presumed micro-endemicity within a well-protected forest, and this likely applies to the newly-discovered species as well.

“The discovery of such a distinctive species within a comparatively well-studied park points towards the gaps in our knowledge of the amphibians of the tropics,” Dr. Scherz said.

“It also highlights the role that bad weather, especially cyclones, can play in bringing otherwise hidden frogs out of hiding — Rhombophryne ellae was caught just as Cyclone Ava was moving in on Madagascar, and several other species my colleagues and I have recently described were also caught under similar cyclonic conditions.”

The discovery is described in the journal Zoosystematics and Evolution.

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M.D. Scherz. 2020. Diamond frogs forever: a new species of Rhombophryne Boettger, 1880 (Microhylidae, Cophylinae) from Montagne d’Ambre National Park, northern Madagascar. Zoosystematics and Evolution 96 (2): 313-323; doi: 10.3897/zse.96.51372