Is the Brazilian flea toad the world’s smallest vertebrate?

Flea frog perching on 1 Brazilian Real (coin diameter is 27 mm)

Renato Gaiga

The tiny Brazilian frog, about the size of a pea, could threaten the current record holder for the world's smallest vertebrate.

flea toad Brachycephalus purex (actually a species of frog) was first described by scientists in 2011. Immediately after that, Mirko Sole Researchers at Brazil's Santa Cruz State University thought this species might be the smallest amphibian ever discovered. But only a few specimens have been collected from the frog's only known habitat, a forested hilltop in southern Bahia, Brazil. Also, the necessary gonad tests to determine whether they were adults were not performed.

Solé and his colleagues measured the lengths of 46 flea toads, examined their gonads, and checked for the presence of throat clefts, which only males have, to determine the frogs' maturity and gender.

adult B. Purex Males have an average body length of over 7 millimeters and are slightly smaller than females. Therefore, they are smaller than males. Phaedophryn amauensisa frog from Papua New Guinea that was previously considered both the smallest amphibian and the smallest vertebrate.

Say “It's perfectly clear.” mark schartz At the Danish Natural History Museum in Copenhagen. “These may actually be the world's smallest living frogs, which is amazing.”

It's not just the average size that's shocking, the smallest specimens in the study show just how small these flea frogs are compared to other minifrogs. “It's 6.45 mm.” [long]That's 30 percent smaller than any adult male frog I've ever seen,” Schertz said. “It's almost a millimeter smaller than the next smallest frog.”

At such small scales, frogs develop strange anatomical peculiarities, such as missing toes and underdeveloped ears. they cannot hear their suitor's song. Some species have very weak balance organs and are barely able to jump.

But Solé says there may also be smaller vertebrates that have yet to be discovered. Perhaps the next record holder could be another small frog or a parasitic male deep-sea anglerfish.

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Source: www.newscientist.com

A new species of toad has been found living in African volcanoes

Scientists have identified a new genus and species of true toad from a single specimen found in a high-altitude forest. mount kenya, an extinct volcano in Kenya and the second highest mountain in Africa after Kilimanjaro. Contrary to the popular belief that most of Kenya’s amphibians arose after volcanic activity subsided millions of years ago, this new species is related to the Kenya volcanic toad (Kenya Phrynoides vulcanis) – Its origins may date back as far as 20 million years, making it considerably older than the volcanic formation of Mt Kenya itself.

artistic performance Kenya Phrynoides vulcanis (A), dorsal view of the left hand of the holotype (B), and photographs of the dorsal (C) and ventral (D) sides of the holotype before preservation. Image credit: Liedtke other., doi: 10.1093/zoolinnean/zlad160.

Dr Simon Loader, lead curator of vertebrates at the Natural History Museum, London, said: ‘Many of Kenya’s mountains are volcanic or geologically relatively new, so discovering ancient lineages that have lasted for millions of years is unlikely. It’s amazing.”

“It’s a real challenge to figure out how it got here.”

“We can’t say for sure, but it seems likely that they were once more widespread, and as the climate has changed over the past tens of millions of years, they have tracked their way through tropical forests, with their final destinations being the mountaintops. It was ‘Mt Kenya’. ”

The discovery of Kenya’s volcanic toads calls into question the concept of the Kenya interval, a term used to describe the striking contrast in amphibian diversity between Kenya and its neighboring countries.

Ethiopia and Tanzania have long been hotspots for amphibian biodiversity, but Kenya’s geological history and frequency of tectonic activity make it a difficult place for these organisms to thrive.

unique features Kenya Phrynoides vulcanis This suggests that the Kenyan Interval may not be as simple as previously believed.

When this toad was first discovered in Mount Kenya’s pit in 2015, it already seemed very different from the species normally seen in the area.

“We were really surprised to see this animal. It looked nothing like anything we had seen before, but it was similar to what we know and call the Tanzanian animal. Ta” Churamiti MaridadiIt is a forest tree toad that lives in the Ukaguru Mountains rainforest,” said National Museums of Kenya curators Dr Patrick Maronza and Dr Victor Wasonga.

Kenya Phrynoides vulcanisDistinctive features include its small size, more frog-like body, and distinctive green and brown markings.

Genetic and morphological differences from other known toad species have led to its recognition at the genus level.

Clues from physical features such as enlarged fingertips suggest it may be a climber.

Its thumb has a sharp tip known as a nuptial spine found in many male frogs and toads, which helps the male grasp the female and encourage reproduction.

“The forest toad found in the mountains of East Africa is unusual and does not resemble typical toads,” said Dr. Hendrik Müller, a researcher at Martin Luther University Halle-Wittenberg.

“More interestingly, some individuals are known to have an unusual reproductive strategy called ovoviviparity.”

“In ovoviviparity, the eggs hatch inside the female’s body. This means that the chicks are born from the mother as small toads, rather than as tadpoles.”

This finding is reported in the following article: paper inside Zoological journal of the Linnean Society.

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H. Christoph Liedtke other. A new species of toad discovered from Mount Kenya sheds light on the biogeography of East Africa’s mountains. Zoological journal of the Linnean Society, published online on November 7, 2023. doi: 10.1093/zoolinnean/zlad160

Source: www.sci.news