New diamond frog species discovery in Madagascar


Rhombophryne ellae. Image credit: Mark Scherz

From ScienceDaily:

Shining like a diamond: A new species of diamond frog from northern Madagascar

June 16, 2020

Despite the active ongoing taxonomic progress on Madagascar’s frogs, the amphibian inventory of this hyper-diverse island is still very far from being complete. The known diversity of the diamond frog genus Rhombophryne in Madagascar has increased significantly (more than doubled!) over the last 10 years, but still there are several undescribed candidate species awaiting description. New species are constantly being discovered in Madagascar, often even within already well-studied areas. One such place is the Montagne d’Ambre National Park in northern Madagascar.

Montagne d’Ambre National Park is widely known for its endemic flora and fauna, waterfalls and crater lakes, and considered to be a relatively well-studied area. Yet, only two studies have been published so far on the reptiles and amphibians of the Park.

Serving the pursuit of knowledge of the herpetofauna in the region, Germany-based herpetologist Dr. Mark D. Scherz (Bavarian State Collection of Zoology, Technical University of Braunschweig, University of Konstanz) published a description of a new diamond frog species: Rhombophryne ellae, in the open-access journal Zoosystematics and Evolution.

“As soon as I saw this frog, I knew it was a new species,” shares Dr. Scherz, “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 recognise that it is a new species without having to wait for the DNA sequence results to come back, so this was elating.”

The new species is most closely related to a poorly-known and still undescribed species from Tsaratanana in northern Madagascar, but is otherwise quite different from all other diamond frogs. With the orange colouration on its legs, Rhombophryne ellae joins the growing list of frogs that have red to orange flash-markings. The function of this striking colouration remains unknown, despite having evolved repeatedly in frogs, including numerous times in Madagascar’s narrow-mouthed frogs alone.

“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. 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,” says Dr. Scherz.

The species is known so far only from a single specimen, making it difficult to estimate its conservation status. Yet, based on the status of other, related frogs from the same area, it will probably be Red-listed as Near Threatened due to its presumably small range and micro-endemicity.

Small new frog species discovery in Madagascar


Life colouration of Stumpffia froschaueri sp. nov. A dorsolateral view of holotype ZSM 169/2019 (ACZCV 0940) from Anketsakely (Anabohazo Forest) B dorsolateral view of paratype ZSM 166/2019 (ACZCV 0939) from Ankarafa Forest C dorsolateral view of paratype ZSM 168/2019 (ACZCV 0966) from Ankarafa Forest D dorsolateral view of paratype ZSM 167/2019 (ACZCV 0968) from Ankarafa Forest. Pictures by Gonçalo M. Rosa

A 25 May 2020 video used to say about itself:

A frog no bigger than a 5p coin has been discovered in Madagascar – and already classed as critically endangered by conservationists. The new species of stump-toed frog, named Stumpffia froschaueri, is brown in colour with black spots on its side, in an apparent attempt to camouflage itself among the leaves around it.

From ScienceDaily:

A new critically endangered frog named after ‘the man from the floodplain full of frogs’

May 25, 2020

A new species proposed to be classified as Critically Endangered of miniaturised stump-toed frog of the genus Stumpffia, found in Madagascar, is named Stumpffia froschaueri after “the man from the floodplain full of frogs,” Christoph Froschauer. The namesake of the new frog is famous for being the first, and European wide renowned, printer from Zürich, famous for printing “Historia animalium” and the “Zürich Bible”.

Christoph Froschauer’s (ca. 1490 — April 1564) family name means “the man from the floodplain full of frogs“, and the printer used to sign his books with a woodcut, showing frogs under a tree in a landscape. Amongst his publications are works by Zwingli, Bullinger, Gessner, Erasmus von Rotterdam and Luther, and as a gift for his art, the printer was given citizenship in Zürich in 1519. Now, scientists have also honoured Froschauer’s great contributions by naming a new frog species after him.

The discovery, made by an international team of scientists from CIBIO (Research Centre in Biodiversity and Genetic Resources) of the University of Porto, Zoological Society of London, University of Lisbon, University of Brighton, University of Bristol, University of Antananarivo and Museo Regionale di Scienze Naturali, is published in the open-access peer-reviewed journal ZooKeys.

The new species is reliably known only from a few specimens collected in three forest patches of the Sahamalaza region, an area severely threatened by fire, drought and high levels of forest clearance.

“In Anketsakely and Ankarafa this species has been found only in areas with relatively undisturbed forest, and active individuals were found during the day within the leaf-litter on the forest floor, where discreet calling males were also detected,” shares lead author Dr. Angelica Crottini from CIBIO.

Even though two out of the three forest patches where Stumpffia froschaueri occurs are now part of a UNESCO Biosphere Reserve, there is a lack in forest border patrols and the area remains under strong pressure from slash-and-burn activities and timber harvesting. Habitat loss and fragmentation are likely to represent a huge threat to the species’ survival and cause population declines, unless remedial actions to enforce the protection of these habitats are taken. The scientists suggest to classify Stumpffia froschaueri as a Critically Endangered species according to criteria of the IUCN Red List.

“We here reiterate the need to continue with field survey activities, giving particular attention to small and marginal areas, where several microendemic candidate species are likely waiting to be discovered and formally described. This description confirms the Sahamalaza Peninsula as an important hotspot of amphibian diversity, with several threatened species relying almost entirely on the persistence of these residual forest fragments,” concludes Dr. Crottini.

Aye-aye lemurs of Madagascar


This 2019 video says about itself:

Aye aye (Daubentonia madagascariensis) – the bizarre lemur, the demon of the night from Madagascar

Aye-aye is one of the most bizarre mammals. It is the largest nocturnal primate in the world. Local people on Madagascar greatly fear this animal and kill it if they can. They believe that aye-aye is a bad spirit and they will die if it appears in the village.

In fact, it is specialized in eating grubs, which it gets our of the holes in the wood by its long middle finger. It taps on the wood before and detects the grub with its huge ears. Aye-aye has always growing incisors which enable it to bite to the wood. Apart from insects, it eats also fruits and seeds and that is why it comes to the plantations. Nobody knows how many aye-ayes are left in the forest of Madagascar.

Dinosaur age mammal discovery in Madagascar


This 29 April 2020 video says about itself:

Macalester Professor helps discover “Crazy Beast” in Madagascar

Raymond Rogers, DeWitt Wallace Professor and chair of the Geology Department, is the co-author of a groundbreaking article published today in the scientific journal Nature. The paper details the discovery of a new mammalian fossil in the Mahajanga Basin in Madagascar.

From Stony Brook University in the USA:

Stony Brook, Long Island, April 29, 2020: In evolutionary terms, islands are the stuff of weirdness. It is on islands where animals evolve in isolation, often for millions of years, with different food sources, competitors, predators, and parasites…indeed, different everything compared to mainland species. As a result, they develop into different shapes and sizes and evolve into new species that, given enough time, spawn yet more new species.

Such is the case with the discovery of a new, bizarre 66-million-year-old mammal in Madagascar by a team of international researchers led by Dr. David Krause, senior curator of vertebrate paleontology at the Denver Museum of Nature & Science and professor emeritus at Stony Brook University, where part of the research was done. The discovery of this opossum-sized mammal that lived among dinosaurs and massive crocodiles on the fourth largest island on Earth was announced today in the journal Nature. Dr. James B. Rossie of Stony Brook University is one of the study’s co-authors. The late Yaoming Hu of Stony Brook University was also a co-author.

The finding of the new mammal, called Adalatherium, which is translated from the Malagasy and Greek languages and means “crazy beast”, is based on a nearly complete skeleton that is astoundingly well preserved. The skeleton is the most complete for any Mesozoic mammal yet discovered in the southern hemisphere.

Krause said that “knowing what we know about the skeletal anatomy of all living and extinct mammals, it is difficult to imagine that a mammal like Adalatherium could have evolved; it bends and even breaks a lot of rules.”

In fact, although a life-like reconstruction might lead one to think that Adalatherium was a run-of-the-mill badger, its “normality” is literally only skin deep. Below the surface, its skeleton is nothing short of “outlandish.” It has primitive features in its snout region (like a septomaxilla bone) that hadn’t been seen for a hundred million years in the lineage leading to modern mammals.

“Its nasal cavity exhibits an amazing mosaic of features, some of which are very standard for a mammal, but some that I’ve never seen in anything before,” Rossie declared.

Adalatherium had more holes (foramina) on its face than any known mammal, holes that served as passageways for nerves and blood vessels supplying a very sensitive snout that was covered with whiskers. And there is one very large hole on the top of its snout for which there is just no parallel in any known mammal, living or extinct.

The teeth of Adalatherium are vastly different in construction than any known mammal. Its backbone had more vertebrae than any Mesozoic mammal and one of its leg bones was strangely curved.

About the size of a Virginia opossum, Adalatherium was also unusual in that it was very large for its day; most mammals that lived alongside dinosaurs were much smaller, mouse-sized on average.

Adalatherium belongs to an extinct group of mammals called gondwanatherians because they are only known from the ancient southern supercontinent of Gondwana. Gondwanatherian fossils were first found in Argentina in the 1980s but have since also been found in Africa, India, the Antarctic Peninsula, and Madagascar. Gondwanatherians were first thought to be related to modern-day sloths, anteaters, and armadillos but “now are known to have been part of a grand evolutionary experiment, doing their own thing, an experiment that failed and was snuffed out in the Eocene, about 45 million years ago”, Krause explained.

Prior to the discovery of the nearly complete skeleton of Adalatherium, gondwanatherians were only known from isolated teeth and jaw fragments, with the exception of a cranium from Madagascar described by Krause and his team in 2014.

The completeness and excellent preservation of the skeleton of Adalatherium potentially opens up new windows into what gondwanatherians looked like and how they lived, but the bizarre features still have the scientific team guessing.

As Krause’s primary collaborator Simone Hoffmann of the New York Institute of Technology put it, “Adalatherium is the oddest of oddballs. Trying to figure out how it moved is nearly impossible because, for instance, its front end is telling us a different story than its back end.” The research team is still uncovering clues but thinks that, although Adalatherium might have been a powerful digging animal, it was also capable of running and potentially even had other forms of locomotion.

The plate tectonic history of Gondwana provides independent evidence for why Adalatherium is so bizarre. Adalatherium was found in rocks dated to near the end of the Cretaceous, at 66 million years ago. Madagascar, with the Indian subcontinent attached to the east, separated from Africa over a hundred million years before and finally became isolated as an island in the Indian Ocean when the Indian subcontinent detached at approximately 88 million years ago and drifted northward. That left the lineage that ultimately resulted in Adalatherium to evolve, isolated from mainland populations, for over 20 million years – “ample time to develop its many ludicrous features,” said Krause.

The fossil record of early mammals from the northern hemisphere is roughly an order of magnitude better than from the south.

“Adalatherium is just one piece, but an important piece, in a very large puzzle on early mammalian evolution in the southern hemisphere,” Krause noted. “Unfortunately, most of the pieces are still missing.”

More than anything, this discovery underscores to the researchers how much more remains to be learned by making new discoveries of early mammals in Madagascar and other parts of the former Gondwana.

In addition to Krause, Hoffmann, and Rossie, other researchers involved in the new discovery – which was funded by the National Science Foundation and National Geographic Society — were: the late Yaoming Hu of Stony Brook University; John R. Wible of Carnegie Museum of Natural History; Guillermo W. Rougier of University of Louisville; E. Christopher Kirk of University of Texas at Austin; Joseph R. Groenke of Stony Brook University and Ohio University; Raymond R. Rogers of Macalester College; Julia A. Schultz of Institut für Geowissenschaften der Universität Bonn, Alistair R. Evans of Monash University and Museums Victoria; Wighart von Koenigswald of Institut für Geowissenschaften der Universität Bonn; and Lydia J. Rahantarisoa of Université d’Antananarivo.

The new Adalatherium mammal is just the latest of a series of bizarre back-boned animals discovered by Krause and his research team on Madagascar over the past 25 years. Earlier discoveries have included a giant, armored, predatory frog (Beelzebufo), a pug-nosed, vegetarian crocodile (Simosuchus), and a small, buck-toothed dinosaur (Masiakasaurus).

The island itself is filled with animals (and plants) found nowhere else on the planet, including hissing cockroaches, giraffe weevils, tomato frogs, Satanic leaf-tailed geckos, panther chameleons, and streaked tenrecs to name a few. And, of course, there is the signature group of mammals – lemurs – made famous in the animated “Madagascar” movies. Only a few thousand years ago, the Madagascar fauna also included 1400-pound elephant birds, gorilla-sized lemurs, and pygmy hippopotamuses.

For more information visit here.

Madagascar ring-tail lemurs´ love life, new research


This 2018 video is called For Ring-Tailed Lemurs, the Ladies Rule | Wild Love.

From ScienceDaily:

Male ring-tail lemurs exude fruity-smelling perfume from their wrists to attract mates

April 16, 2020

Humans aren’t the only primates who like smelling nice for their dates. In the journal Current Biology on April 16, scientists report that male ring-tailed lemurs (Lemur catta) become more attractive to females by secreting a fruity and floral aroma from their wrists. Using detailed chemical analysis, the researchers identified three compounds responsible for this sweet scent, marking the first time that pheromones have been identified in a primate.

“During the yearly breeding season, male lemurs rub the glands on their wrists against their fluffy tails and then wave them at females in a behavior called ‘stink flirting'”, says senior author Kazushige Touhara, professor and biochemist at the University of Tokyo.

Ring-tailed lemurs have well-developed scent glands on their shoulders and wrists. These glands are typically used to designate social rank, territory, and reproductive status. However, behavioral observations show they also use their scent glands to catch the attention of females. “Since only ring-tailed lemurs have these wrist glands and exhibit ‘stink flirting’ behavior, we reasoned that specific odorants for sexual communication must be involved,” Touhara says.

At the Japanese Monkey Center (JMC) in Aichi and The Research Institute of Evolutionary Biology in Tokyo, Japan, Touhara and his team tracked the behavior of a conspiracy of ring-tailed lemurs. They observed that female lemurs sniffed the scent markings left by males more often and for longer periods of time during the breeding season — when females are sexually receptive. Furthermore, when researchers isolated the primate perfume from four males and presented it to females individually, they found that females sniffed the fruity-smelling odor for roughly twice as long as the bitter-smelling gland secretions produced off-season.

“Females sniff the floral and fruity scent for a few more seconds than the controls and occasionally even lick it. Although this sounds like a very short time, it’s enough to recognize or evoke curiosities in the male,” says Touhara.

Using gas chromatography-mass spectrometry analysis on the of the wrist-gland secretions produced during breeding and non-breeding seasons, Touhara determined the major chemical components making up the male scents. Three aldehyde compounds — dodecanal, 12-methyltridecanal, and tetradecanal — were present in both odors but showed substantially higher concentrations during the breeding season. Moreover, when the compounds were individually presented to females in the JMC enclosure, researchers found that only the mixture of all three had a significant ability to hold a female’s attention.

“All three compounds have been suggested to be involved in the recognition of newborn sheep by their mothers, and tetradecanal is known as a sex pheromone in some insect species. Although this is the first time 12-methyltridecanal has been identified in primate species, all three aldehydes appear to be used as communication tools widely throughout the animal kingdom,” says Touhara.

Young, sexually mature males naturally produce more of these compounds than their senior male counterparts — most likely because aged males produce less testosterone. Furthermore, scientists have observed that females past their reproductive prime are altogether unimpressed by the fruity-smelling odors males exude. These findings suggest that the three compounds are, indeed, pheromones, but more work is required to determine whether they directly influence sexual behavior. “While we have not examined behavioral changes after the sniff in detail, this is an area for future work to determine whether these pheromones impact mating success.”

Madagascar sifaka lemurs’ problems getting food


This 30 December 2019 video says about itself:

Sifaka Lemurs Make A Treacherous Journey For Food | BBC Earth

Sifaka lemurs in Madagascar have to make a perilous journey with babies on board to reach their next feeding area.

Madagascar aye-aye lemurs have six fingers


This June 2015 video says about itself:

Brian Cox Meets An Aye-Aye | Wonders of Life | BBC

Professor Brian Cox gets a rare and up-close look at a sedated aye-aye, known for it’s unusual way of hunting for food.

By Sofie Bates in Science News, October 22, 2019 at 4:25 pm:

Aye-ayes just got weirder with the discovery of a tiny, sixth ‘finger’

An extra digit, a pseudothumb, may help the primates grip objects

Aye-ayes just got even more unusual. The tiny lemurs of Madagascar, known for their large cartoonish ears and continuously growing incisor teeth, also have a sixth “finger” on each hand.

The extra digit — a nubby little “pseudothumb” made of bone and cartilage — can move in three directions and carries its own distinctive fingerprint, researchers report October 21 in the American Journal of Physical Anthropology.

“It’s more than just a nub. It actually has a lot of function to it,” says study coauthor Adam Hartstone-Rose, a comparative anatomist at North Carolina State University in Raleigh. The pseudothumb, which is manipulated by three muscles, may help aye-ayes (Daubentonia madagascariensis) grip objects or branches.

It’s the first time that a pseudothumb has been discovered on any primate, although some people are born with extra fingers (SN: 6/12/19). Other species also have pseudothumbs, including giant pandas, which use their sixth digits to grasp bamboo stalks (SN: 1/31/19). Giant pandas may have acquired that extra digit after the rest of their fingers became less specialized so that the bears could better walk. That’s not the case with aye-ayes, though, the scientists think.

Instead, the little lemurs’ hands may have become too specialized, with thin, elongated fingers, including an especially long third digit that has a ball-and-socket joint. That finger, in particular, is used in a hunting technique called tap foraging, where the animals tap the finger on dead and rotting wood and use echolocation to find bugs hiding inside. Then the primates bite the wood, puncturing a hole, and again use their long third finger for fishing out bugs and grubs found inside.

“Their fingers became so long and spindly that they were no longer good at finger stuff, like grasping,” Hartstone-Rose suggests. The pseudothumb may compensate for the aye-ayes’ other, overspecialized fingers, he and colleagues say.

This interpretation is plausible, says John Hutchinson, an evolutionary biologist at the Royal Veterinary College at the University of London, who was not involved in the work. But he notes that, in general, scientists “don’t know much about what false digits do in most species.”

Extinct giant lemurs of Madagascar


This 25 September 2019 video says about itself:

Just a few thousand years ago, the island of Madagascar was inhabited by giant lemurs. How did such a diverse group of primates evolve in the first place, and how did they help shape the unique environments of Madagascar? And how did they get winnowed down, leaving only their smaller relatives behind?

Blue stick insects discovery in Madagascar


Living specimens of the newly described species of Achrioptera. (A) A. fallax, adult male, captive-bred, reared from eggs of a female from Ankarana (FGZC 1853); (B) A. fallax, mating couple from Daraina (Bekaraoka) (photo by Louis Nusbaumer); (C) A. fallax, adult female with exposed wings from Ankarana National Park (FGZC 1853); (D) A. manga, adult male paratype (FGZC 1334) from Foret d'Orangea; (E) A. manga, adult female; (F) A. spinosissima, adult male reared from eggs collected at Marofandilia, near the type locality in west Madagascar (photo by Bruno Kneubühler); (G) A. maroloko sp. nov., adult male paratype (FGZC 4052) reared from eggs collected at Montagne des Français in dorsolateral view; (H) A. maroloko, adult female paratype (FGZC 4055), bred in captivity from ancestors of Montagne des Français (photo by Moritz Grubenmann)

From Frontiers in Ecology and Evolution:

Love Island: Flamboyant males get the girls on Madagascar

In two new species of rare giant stick insects, males turn livid blue or multicolored at sexual maturity — but why?

April 2, 2019

Summary: Scientists have discovered two new species of giant stick insect on Madagascar, whose males become dazzling blue or multicolored at sexual maturity. The researchers describe their rare and exciting findings, and wonder at the reproductive success of the least stick-like stick insects on the planet.

Biodiversity hotspot Madagascar is one of the world’s biggest islands, and home to some of its biggest insects. Now German scientists have discovered two new species of giant stick insect, living only in the dry forests of Madagascar’s northernmost tip.

One giant female measures a whopping 24cm — but it is the smaller males that are most striking. At sexual maturity these daredevils abandon their stick-like camouflage for dazzling blue or many-colored shining armor.

Writing in Frontiers in Ecology and Evolution, the researchers describe their rare and exciting findings, and wonder at the reproductive success of the least stick-like stick insects on the planet.

When two become four

“Nearly all of the 3000+ known species of stick insects try to be inconspicuous and just look like twigs,” says senior author Dr. Sven Bradler of the University of Göttingen, Germany. “There are a very few, very large exceptions — and we have just discovered a couple more of them.”

The authors re-examined specimens they’d previously identified as odd-looking examples of two existing giant stick insect species, whose adult males remarkably are bright blue or multicolored.

“These were similar in size — 15 to 24cm — but generally less spiny and a bit differently colored than typical examples of their kind,” explains Bradler. “Now genetic tests confirm that the quirky individuals are in fact two new species, distinct from the original two but part of the same group.” explains Bradler.

Bradler’s reclassification places members of this group of species as close evolutionary relatives to other Madagascan stick insects, rather than cousins from overseas as previously thought. This is a potentially major finding, as it challenges the prevailing view that sticks insects colonized Madagascar multiple times.

He who dares, wins

The discovery also prompted the researchers to wonder: what reproductive advantage do these males gain from their bright colors, that is worth exposing themselves to predators?

The first author Dr. Frank Glaw of the Bavarian State Collection of Zoology in Munich, and colleagues bred the new giant stick insect species in captivity to observe their behavior.

“Males of one species started mating attempts only when they achieved their bright blue color.”

This might suggest that the males use their bright coloring to attract a mate. However, it is hard to believe the males could find a mate before being eaten — unless their bright coloring acts as a deterrent to predators.

“Males searching for a mate have to move about more, so pretending to be a stick becomes tricky. Better perhaps to plump for the opposite: a brightly colored warning.”

Bright colors — suggestive of toxicity — keep safe vivid members of other typically camouflaged species, like lividly colored Madagascan frogs.

“In support of this, all stick insects have neck glands that [produce] repellant substances, and these are typically well-developed in brightly colored species. Alternatively, like the Madagascan frogs some giant stick insects may have developed the ability to accumulate toxins from their food.”

But testing these hypotheses will be tough, admits Glaw.

Bradler adds “More than one factor may have played a role in the evolution of this remarkably conspicuous coloration. So even with more data on mate selection, habits, predators, natural food plants, toxins produced by defense glands and possible accumulation of toxins among giant stick insects, finding evidence for these ideas may prove difficult.”

Colorful stick insects have a bright future

Whatever its function, the splendid coloring of the male giant stick insects could make them a strong flagship species to promote the unique biodiversity of Madagascar, and the need for its protection.

“Already the once-uncertain future of these two new species seems secured, with their forest habitat in northern Madagascar a hotspot for conservation priorities”, says Glaw. “It is vital to maintain awareness and motivation to keep logging at bay. This precious area also harbors the highest density of critically endangered reptiles in Madagascar and is home of one of the most threatened primate species in the world, the lemur Lepilemur septentrionalis.”

Five new frog species discovered in Madagascar


An adult male Mini scule Madagascar frog resting on a fingertip. Credit: Photo by Sam Hyde Roberts

From the Ludwig-Maximilians-Universität München in Germany:

Five new frog species from Madagascar

March 28, 2019

Scientists at Ludwig-Maximilians-Universitaet (LMU) in Munich and the Bavarian State Collection of Zoology have named five new species of frogs found across the island of Madagascar. The largest could sit on your thumbnail, the smallest is hardly longer than a grain of rice.

Madagascar, an island a little larger than mainland France, has more than 350 frog species. This number of recognized species is constantly rising, and many of the newly named species are very small.

Mark D. Scherz, a PhD candidate at LMU Munich, and Dr. Frank Glaw, Head of the Herpetology Section at the Bavarian State Collection of Zoology in Munich, together with colleagues at the Technical University of Braunschweig and the University of Antananarivo have named five new species of tiny frogs found across the island. Their study appears in the online journal PLOS ONE.

The five new species belong to a group of frogs commonly referred to as ‘narrow-mouthed’ frogs, a highly diverse family found on every continent except Antarctica and Europe. Although most narrow-mouthed frogs are small to moderately large, many are tiny. In fact, the group includes the smallest frog in the world — Paedophryne amauensis from Papua New Guinea, mature specimens of which reach a length of only 7.7 mm. What’s remarkable is that, in the smallest frogs, “miniaturization” has evolved independently — often several times within a single region, as highlighted in this new study. Three of the new species belong to a group that is wholly new to science, which the authors have formally dubbed Mini. The other two new species, Rhombophryne proportionalis and Anodonthyla eximia, are also just 11-12 mm long, and are much smaller than their closest relatives.

“When frogs evolve small body size, they start to look remarkably similar, so it is easy to underestimate how diverse they really are,” says Mark D. Scherz, lead author on the new study. “Our new genus name, Mini, says it all. Adults of the two smallest species Mini mum and Mini scule are 8-11 mm long, and even the largest member of the genus, Miniature, at 15 mm, could sit on your thumbnail with room to spare.”

Finding tiny frogs in the leaf litter is hard work. “Calling males often sit one or two leaves deep and stop calling at the slightest disturbance”, says Frank Glaw. “It can take a lot of patience to find the frog you are looking for.”