Zoosystematics and Evolution

What can we learn from vanishing wildlife species: the case of the Pyrenean Ibex

The sad history of the Pyrenean Ibex (Capra pyrenaica pyrenaica) is a powerful example of species loss due to causes related to human activity. DNA analyses of Pyrenean Ibex found evidence that, after a demographic expansion about 20,000 years ago, its population went through a bottleneck caused by hunting, inbreeding and other factors, which ultimately caused its extinction. Their research is published in the open-access, peer-reviewed journal Zoosystematics and Evolution.

*Only the French mountaineer and photographer Bernhard Clos managed to take a series of good photos of the Bucardo, as the Pyrenean Ibex is called on the Spanish side. Photo: Bernhard Clos*

Likely the first extinction event of the 2000s in Europe, the sad history of the Pyrenean Ibex (Capra pyrenaica pyrenaica) is a powerful example of the ever-increasing species loss worldwide due to causes related to human activity. It can, however, give us valuable information on what should be done (or avoided) to halt this extinction vortex.

The distribution of this subspecies of Iberian Ibex was limited to the French and Spanish Pyrenees. Its first mention in an official written document, dating back to 1767, already refers to it as extremely rare. Like many other mountain goats, it was almost hunted to extinction before its killing became prohibited in 1913. Neither the institution of a national park (Ordesa & Monte Perdido), nor a conservation project with European LIFE program funding could stop the extinction of the Pyrenean Ibex eventually officialised on January 6, 2000. But the story of this charismatic animal did not end there – a controversial cloning program was started instantly with no scientific agreement, nor support from regional environmental NGOs, claiming that de-extinction was possible even in the absence of further DNA studies.

Laña, the last surviving Pyrenean Ibex, returned as a mounted animal to Torla-Ordesa on the 6th November 2012 after its controversial cloning attempt. Her skin is now exhibited in the visitors centre of Ordesa & Monte Perdido National Park. Photo: Manolo Grasa

To find out more about the drivers of its extinction, an international team composed of 7 nationalities built a database of all known museum specimens and reconstructed the demographic history of the Pyrenean Ibex based on DNA evidence. Their research is published in the open-access, peer-reviewed journal Zoosystematics and Evolution.

The research found that after a population expansion between 14,000 and 29,000 years ago (which is quite recent from a genetic point of view), a significant loss of genetic diversity followed between approximately 15,000 and 7,500 years BP, and continued until present. By that time, the Pyrenean Ibex also lived outside the Pyrenean mountain chain, but, gradually, its distribution was reduced to only one valley in the Ordesa National Park in the Spanish Pyrenees.

*The adventures of the British hunter E.N. Buxton were published in 1893. This engraving represents a hunting party in the Ordesa Valley (Spanish Pyrenees).*

Written sources confirm hunting of the Pyrenean Ibex from as early as the 14th century, and during the 19th and 20th century it became a common target for trophy hunters. Undoubtedly, hunting played an important role in reducing its population numbers and distribution area, but it is not possible – with the information currently available – to pinpoint it as the straw that broke the camel’s back. Infectious diseases that originate from livestock (for instance, those caused by the bluetongue virus, BTV, and sarcopses) are capable of decimating other subspecies of Iberian Ibex in extremely short periods of time.

While the relative contribution of various factors remains largely unknown, it seems that hunting and diseases transmitted from other animals have been effective in drastically reducing the number of Pyrenean ibexes over the last two centuries, because they were acting on an already genetically weakened population. This low genetic diversity, combined with inbreeding depression and reduced fertility, brought the population beyond the minimum viable size – from that point onwards, extinction was inevitable.

This case study shows the importance of historical biological collections for genetic analyses of extinct species. A privately owned 140-year-old trophy preserved in Pau, France, was genotyped as part of this research, showing that private individuals may possess material of high value. As there is little knowledge of such resources, the authors call for the creation of an online public database of private collections hosting biological material for the benefit of biodiversity studies.

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Original source:
Forcina G, Woutersen K, Sánchez-Ramírez S, Angelone S, Crampe JP, Pérez JM, Fandos P, Granados JE, Jowers MJ (2021) Demography reveals populational expansion of a recently extinct Iberian ungulate. Zoosystematics and Evolution 97(1): 211-221. https://doi.org/10.3897/zse.97.61854

Highlands of diversity: Another new chameleon from the Bale region, Ethiopia

The Bale Mountains in south-central Ethiopia are considered to be one of the most unique centers of endemism, with an extraordinary number of plants and animals that can only be found there. Numerous species are already known from this Afromontane high-elevation plateau, making it a biodiversity hotspot, but ongoing research continues to reveal the presence of so far unknown and undescribed organisms.

The new chameleon species, *Trioceros wolfgangboehmei*
Credit: Koppetsch et al.

Zoologists Thore Koppetsch and Benjamin Wipfler of the Research Museum Alexander Koenig in Bonn, Germany, and Petr Nečas from the Czech Republic, describe one such species: a new small-sized chameleon living on the edge of the forest. Their findings were published in the open-access, peer-reviewed life science journal Zoosystematics and Evolution.

There were already two species of the chameleon genus Trioceros known to be restricted to the Bale region when Thore Koppetsch and his colleagues discovered another unique representative of this group from the northern slopes of the Bale Mountains. Interestingly, this new chameleon is considered to be part of a species complex of the wide-spread Ethiopian Chameleon Trioceros affinis. Previous studies have indicated divergence between its different populations across the Ethiopian Highlands – with some of them separated by the northern extension of the Great Rift Valley, which also shaped the evolution of early humans.

Living individual of *Trioceros wolfgangboehmei*
Credit: Koppetsch et al.

The new chameleon, Trioceros wolfgangboehmei, has a special name. It honours the scientific work of Wolfgang Böhme, senior herpetologist at the Zoological Research Museum Alexander Koenig in Bonn, and his passion for chameleons and other reptiles.

Apart from its biogeographical patterns, the new species also has a characteristic appearance, displaying enlarged spiny scales on its back and tail that form a prominent crest. It usually lives on small trees and bushes at an altitude of above 2,500 m above sea level.

Head detail of the new chameleon, *Trioceros wolfgangboehmei*
Credit: Koppetsch et al.

“Given the variation in colour patterns and morphology between different populations of these chameleons in Ethiopia, it is likely that these groups still bear a higher hidden diversity than expected, which might be revealed by further ongoing investigations.”
Thore Koppetsch

Furthermore, the research team urges for sustainable preservation and conservation of its habitat to mitigate the impact of human activity.

***

Original source:

Koppetsch T, Nečas P, Wipfler B (2021) A new chameleon of the Trioceros affinis species complex (Squamata, Chamaeleonidae) from Ethiopia. Zoosystematics and Evolution 97 (1): 161–179. https://doi.org/10.3897/zse.97.57297

Agents of food-borne zoonoses confirmed to parasitise newly-recorded in Thailand snails

Parasitic flatworms known as agents of food-borne zoonoses were confirmed to use several species of thiarid snails, commonly found in freshwater and brackish environments in southeast Asia, as their first intermediate host. These parasites can cause severe ocular infections in humans who consume raw or improperly cooked fish that have fed on infected snails. The study, conducted in South Thailand by Thai and German researchers and led by Kitja Apiraksena, Silpakorn University, is published in the peer-reviewed open-access journal Zoosystematics and Evolution.

“Trematode infections are major public health problems affecting humans in southeast Asia. Trematode infections depend not only on the habit of people, but also on the presence of first and second intermediate host species, resulting in the endemic spread of parasites, such as intestinal and liver flukes in Thailand”.
explain the scientists.

The snails of concern belong to the genus Stenomelania, have elongated and pointed shells and can be found near and in the brackish water environment of estuaries in the Oriental Region, from India to the Western Pacific islands. Worryingly enough, science does not know much else about these snails to date. Further, these species are hard to distinguish from related trumpet snails, because of the similarities in their shell morphology.

In order to provide some basic knowledge about the parasitic worms in Thailand and neighbouring countries, the research team collected a total of 1,551 Stenomelania snails, identified as four species, from streams and rivers near the coastline of the south of Thailand in Krabi, Trang and Satun Provinces. Of them, ten were infected with trematodes. The parasites were found at seven of the studied localities and belonged to three different species. In Krabi Province, the researchers observed all three species.

Speculating on their presence, the scientists suspect that it could be related to the circulation of sea currents, as the flow of water along the Andaman coast is affected by the monsoon season.

In conclusion, the researchers note that it is a matter of public health that further research looks into the biodiversity and biology of these snails, in order to improve our knowledge about the susceptibility of Stenomelania snails to food-borne zoonotic.

“This finding indicated that the resulting parasitic diseases are still largely neglected in tropical medicine, so further studies should be performed on the prevalence of various trematode-borne diseases in locations with snail occurrences in Thailand,”
they say.

Research article:

Apiraksena K, Namchote S, Komsuwan J, Dechraksa W, Tharapoom K, Veeravechsukij N, Glaubrecht M, Krailas D (2020) Survey of Stenomelania Fisher, 1885 (Cerithioidea, Thiaridae): The potential of trematode infections in a newly-recorded snail genus at the coast of Andaman Sea, South Thailand. Zoosystematics and Evolution 96(2): 807-819. https://doi.org/10.3897/zse.96.59448

Notice me! Neglected for over a century, Black sea spider crab re-described

After the revision of available type specimens from all available collections in the Russian museums and the Senckenberg Museum in Frankfurt-on-Main, as well as newly collected material in the Black Sea and the North-East Atlantic, a research team of scientists, led by Dr Vassily Spiridonov from Shirshov Institute of Oceanology of Russian Academy of Sciences, re-described Macropodia czernjawskii and provided the new data on its records and updated its ecological characteristics.

Even though recognised in the Mediterranean Sea, the Macropodia czernjawskii spider crab was ignored by scientists (even by its namesake Vladimir Czernyavsky) in the regional faunal accounts of the Black Sea for more than a century. At the same time, although other species of the genus have been listed as Black sea fauna, those listings are mostly wrong and occurred either due to historical circumstances or misidentifications.Now, scientists re-describe this, most likely, only species of the genus occurring in the Black Sea in the open-access journal Zoosystematics and Evolution.

The studied spirder crab species *Macropodia czernjawskii* in the wild, Tuaphat (near Gelendzhik), Caucasus, Black Sea.
Photo by Sergey Anosov

The spider crab genus Macropodia was discovered in 1814 and currently includes 18 species, mostly occurring in the Atlantic and the Mediterranean. The marine fauna of the Black Sea is predominantly of Mediterranean origin and Macropodia czernjawskii was firstly discovered in the Black Sea in 1880, but afterwards, its presence there was largely ignored by the scientists.

After the revision of available type specimens from all available collections in the Russian museums and the Senckenberg Museum in Frankfurt-on-Main, as well as newly collected material in the Black Sea and the North-East Atlantic, a research team of scientists, led by Dr Vassily Spiridonov from Shirshov Institute of Oceanology of Russian Academy of Sciences, re-described Macropodia czernjawskii and provided the new data on its records and updated its ecological characteristics.

“The analysis of the molecular genetic barcode (COI) of the available material of Macropodia species indicated that M. czernjawskii is a very distinct species while M. parva should be synonimised with M. rostrata, and M. longipes is a synonym of M. tenuirostris”,
states Dr Spiridonov sharing the details of the genus analysis.

All Macropodia species have epibiosis and M. czernjawskii is no exception: almost all examined crabs in 2008-2018 collections had significant epibiosis. It normally consists of algae and cyanobacteria and, particularly, a non-indigenous species of red alga Bonnemaisonia hamifera, officially reported in 2015 at the Caucasian coast of the Black Sea, was found in the epibiosis of M. czernjawskii four years earlier.

“It improves our understanding of its invasion history. Museum and monitoring collections of species with abundant epibiosis (in particular inachid crabs) can be used as an additional tool to record and monitor introduction and establishments of sessile non-indigenous species,”
suggests Dr Spiridonov.

The spider crab species *Macropodia czernjawskii* in the wild, Tuaphat (near Gelendzhik), Caucasus, Black Sea.
Photo by Sergey Anosov

***

Original source:

Spiridonov VA, Simakova UV, Anosov SE, Zalota AK, Timofeev VA (2020) Review of Macropodia in the Black Sea supported by molecular barcoding data; with the redescription of the type material, observations on ecology and epibiosis of Macropodia czernjawskii (Brandt, 1880) and notes on other Atlanto-Mediterranean species of Macropodia Leach, 1814 (Crustacea, Decapoda, Inachidae). Zoosystematics and Evolution 96(2): 609-635. https://doi.org/10.3897/zse.96.48342

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

Despite the active ongoing taxonomic progress on the Madagascar frogs, the amphibian inventory of this hyper-diverse island is still very far from being complete. More new species are constantly being discovered, often within already well-studied areas. So, in one of the relatively well-studied parks in northern Madagascar, a new species of diamond frog, Rhombophryne ellae, was found in 2017. Now, the discovery is published in the open-access journal Zoosystematics and Evolution.

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.

*Rhombophryne ellae* was captured just as Cyclone Ava began to make itself felt across Madagascar with high winds and heavy rain. The camp where Dr. Scherz and his team were based became flooded, with rivers running through the kitchen and sleeping area. Miserable weather for humans, but a time of increased activity for some of the more elusive amphibians of the forest.
Credit: Mark D. Scherz
License: CC-BY 4.0

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.

Rhomobphryne ellae
Credit: Mark D. Scherz
License: CC-BY 4.0

“As soon as I saw this frog, I knew it was a new species. 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”,
shares Dr. Scherz.

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 new species, *Rhombophryne ellae*, is well camouflaged among the rainforest leaflitter
Credit: Mark D. Scherz
License: CC-BY 4.0

“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.

*Rhombophryne ellae* is a small, probably semi-fossorial (sub-terranean-dwelling) species of diamond frog, at home amongst the leaf litter of Montagne d’Ambre National Park, north Madagascar
Credit: Mark D. Scherz
License: CC-BY 4.0

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.

Original source:

Scherz MD (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. https://doi.org/10.3897/zse.96.51372

A new character for Pokémon? Novel endemic dogfish shark species discovered from Japan

A new endemic deep-water dogfish shark: Squalus shiraii, was discovered in the tropical waters of Southern Japan by an international team of scientists led by Dr. Sarah Viana from South African Institute for Aquatic Biodiversity. The finding brings the amount of spurdogs shark species inhabiting Japanese waters to six. The discovery is published in the open-access journal Zoosystematics and Evolution.

Newly discovered creatures can often be as impressive and exciting as the ones from the Japanese movies and shows. Many of those fictional characters, including inhabitants of the famous Pokémon universe, might have their analogues among the real animals native to Japan. Maybe, a new species of the dogfish shark published in the open-access journal Zoosystematics and Evolution is also “a real Pokémon” to be?

A new deep-water dogfish shark: Squalus shiraii, was discovered in the tropical waters of Southern Japan by an international team of scientists, led by Dr. Sarah Viana from South African Institute for Aquatic Biodiversity.

Map of the North-western Pacific Ocean, showing the geographical distribution of *Squalus shiraii*
Credit: Sarah Viana
License: CC-BY 4.0

The new shark has the body length of 59-77 cm and some unique characteristics such as tall first dorsal fin and caudal fin with broad white margins. Currently, the species is known exclusively as a Japanese endemic, occurring in the tropical shallow waters of Southern Japan in the North-western Pacific.

*Squalus shiraii* lateral view
Credit: Sarah Viana
License: CC-BY 4.0

Spurdogs represent commercially important for the world fish trade taxa. They are caught for a range of purposes: consumption of meat, fins and liver oil. Despite their high occurrence, the accurate identification data of species is scarce, population threats and trends remain unknown.

Japan currently represents one of the world’s leading shark fish trade countries, though, during the last decades the amount of shark catches is decreasing and over 78 elasmobranch species traded in Japanese shark fin markets are now evaluated as threatened.

The new species Squalus shiraii previously used to be massively misidentified with shortspine spurdog, due to the resembling shape of body, fins and snout length. However, there are some differences, defining the specificity of the new species.

“Squalus shiraii has body brown in colour, postventral and preventral caudal margins whitish, dorsal and ventral caudal tips broadly white and black upper caudal blotch evident in adults. S. mitsukurii has body conspicuously black to dark grey and caudal fins black throughout with post-ventral caudal margin fairly whitish and black upper caudal blotch not evident in adults”, shares lead author Dr. Viana.

Scientists propose the name for the newly described species as Shirai’s spurdog in honour to Dr. Shigeru Shirai, the former Japanese expert of the group.

Original source:
Viana STFL, Carvalho MR (2020) Squalus shiraii sp. nov. (Squaliformes, Squalidae), a new species of dogfish shark from Japan with regional nominal species revisited. Zoosystematics and Evolution 96(2): 275-311. https://doi.org/10.3897/zse.96.51962

Contact:
Dr. Sarah Viana
Email: stviana@gmail.com

Welcome to the House of Slytherin: Salazar’s pit viper, a new green pit viper from India

During an expedition to Arunachal Pradesh in India, part of the Himalayan biodiversity hotspot, a new species of green pit viper Trimeresurus salazar with unique stripes and colouration patterns was discovered near Pakke Tiger Reserve. Scientists named the snake after J.K. Rowling’s fictional character, the Parselmouth wizard and the founder of one of the houses in the magical school Hogwarts, Salazar Slytherin. The discovery is published in the open-access journal Zoosystematics and Evolution.

A new green pit viper species of the genus Trimeresurus was discovered during the herpetological expedition to Arunachal Pradesh in India, part of the Himalayan biodiversity hotspot. The scientists named the newly-discovered snake Trimeresurus salazar after a Parselmouth (able to talk with serpents) wizard, co-founder of Hogwarts School of Witchcraft and Wizardry and the founder of the House of Slytherin – Salazar Slytherin, the fictional character of J.K. Rowling’s saga “Harry Potter”. The discovery is published in the open-access journal Zoosystematics and Evolution.

The pit vipers in the genus Trimeresurus are charismatic venomous serpents, distributed widely across east and southeast Asia. In total, the genus includes at least 48 species, with fifteen representatives occurring in India. The species belonging to the genus are morphologically cryptic, which makes it difficult to distinguish them in the field. As a result, their real diversity could be underestimated.

Arunachal Pradesh, where the new species was found, belongs to the Himalayan biodiversity hotspot, which explains the diverse flora and fauna being continuously discovered there.

The new green pit viper demonstrates a unique orange to reddish stripe, present on the head and body in males.

*Trimeresurus salazar* sp. nov. juvenile male from Pakke Tiger Reserve.
Credit: Aamod Zambre and Chintan Seth, Eaglenest Biodiversity Project.
License: CC-BY 4.0

Explaining the name of the new species, the scientists suggest that it is colloquially referred to as the Salazar’s pit viper.

This is already the second species discovered within the course of the expedition to Arunachal Pradesh, which reflects the poor nature of biodiversity documentation across north-eastern India.

“Future dedicated surveys conducted across northeastern India will help document biodiversity, which is under threat from numerous development activities that include road widening, agriculture, and hydro-electric projects”, shares the lead researcher Dr. Zeeshan A. Mirza from National Centre for Biological Science of Bangalore, India.

*Trimeresurus salazar* sp. nov. holotype male BNHS 3554 in life
Credit: Zeeshan Mirza et al., 2020
License: CC-BY 4.0

Additional information

Contact:
Dr. Zeeshan A. Mirza
Email: snakeszeeshan@gmail.com
Facebook: https://www.facebook.com/snakeszeeshan
Instagram: zeeshan_a_mirza

Original source:

Mirza ZA, Bhosale HS, Phansalkar PU, Sawant M, Gowande GG, Patel H (2020) A new species of green pit vipers of the genus Trimeresurus Lacépède, 1804 (Reptilia, Serpentes, Viperidae) from western Arunachal Pradesh, India. Zoosystematics and Evolution 96(1): 123-138. https://doi.org/10.3897/zse.96.48431

New species of stiletto snake capable of sideways strikes discovered in West Africa

*The first discovered specimen of the newly described species (Atractaspis branchi or Branch’s Stiletto Snake) in its natural habitat. Photo by Mark-Oliver Roedel.*

Following a series of recent surveys in north-western Liberia and south-eastern Guinea, an international team of researchers found three stiletto snakes which were later identified as a species previously unknown to science.

The discovery, published in the open-access journal Zoosystematics and Evolution by the team of Dr Mark-Oliver Roedel from the Natural History Museum, Berlin, provides further evidence for the status of the western part of the Upper Guinea forest zone as a center of rich and endemic biodiversity.

Curiously, stiletto snakes have unusual skulls and venom delivery system, allowing them to attack and stab sideways with a fang sticking out of the corner of their mouths. While most of these burrowing snakes are not venomous enough to kill a human – even though some are able to inflict serious tissue necrosis – this behaviour makes them impossible to handle using the standard approach of holding them with fingers behind the head. In fact, they can even stab with their mouths closed.

The new species, called Atractaspis branchi or Branch’s Stiletto Snake, was named to honor to the recently deceased South African herpetologist Prof. William Roy (Bill) Branch, a world leading expert on African reptiles.

*The first specimen was found at night, moving along the steep slope on the left bank of the small creek (Liberia). Photo by Mark-Oliver Roedel.*

The new species lives in primary rainforest and rainforest edges in the western part of the Upper Guinea forests. Branch’s Stiletto Snake is most likely endemic to this area, a threatened biogeographic region already known for its unique and diverse fauna.

The first specimen of the new species was collected at night from a steep bank of a small rocky creek in a lowland evergreen rainforest in Liberia. Upon picking it up, the snake tried to hide its head under body loops, bending it at an almost right angle, so that its fangs were partly visible on the sides. Then, it repeatedly stroke. It is also reported to have jumped distances almost as long as its entire body. The other two specimens used for the description of the species were collected from banana, manioc and coffee plantations in south-eastern Guinea, about 27 km apart.

“The discovery of a new and presumably endemic species of fossorial snake from the western Upper Guinea forests thus is not very surprising,” conclude the researchers. “However, further surveys are needed to resolve the range of the new snake species, and to gather more information about its ecological needs and biological properties.”

*Close up of the Branch’s Stiletto Snake in its natural habitat. Photo by Mark-Oliver Roedel.*

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Original source:

Rödel M, Kucharzewski C, Mahlow K, Chirio L, Pauwels OSG, Carlino P, Sambolah G, Glos J (2019) A new stiletto snake (Lamprophiidae, Atractaspidinae, Atractaspis) from Liberia and Guinea, West Africa. Zoosystematics and Evolution 95(1): 107-123. https://doi.org/10.3897/zse.95.31488

Life in the fast flow: Tadpoles of new species rely on ‘suction cups’ to keep up

The frogs living in the rainforest of Sumatra also represent a new genus

Indonesia, a megadiverse country spanning over 17,000 islands located between Australia and mainland Asia, is home to more than 16% of the world’s known amphibian and reptile species, with almost half of the amphibians found nowhere else in the world. Unsurprisingly, biodiversity scientists have been feverishly discovering and describing fascinating new animals from the exotic island in recent years.

Such is the case of an international team from the University of Hamburg, Germany, University of Texas at Arlington, USA, University of Bern, Switzerland and Bandung Institute of Technology, Indonesia, who came across a curious tadpole while collecting amphibian larvae from fast-flowing streams as part of an arduous expedition in the remote forests on the island of Sumatra.

To the amazement of the scientists, it turned out that the tadpoles possess a peculiar cup-like structure on their bellies, in addition to the regular oral disk found in typical tadpoles. As a result, the team described two new species and a genus in the open access journal Zoosystematics and Evolution. A previously known, but misplaced in an unsuitable genus, frog was also added to the group, after it was proved that it takes advantage of the same modification.

“This phenomenon where tadpoles display ‘belly suckers’ is known as gastromyzophory and, albeit not unheard of, is a rare adaptation that is only found in certain toads in the Americas and frogs in Asia,” explains lead author Umilaela Arifin.

The abdominal sucker, it is hypothesized, helps these tadpoles to exploit a very special niche – fast-flowing streams – where the water would otherwise be too turbulent and rapid to hang around. Gastromyzophorous species, however, rely on the suction provided by their modified bellies to secure an exclusive access to plentiful food, such as algae, while the less adapted are simply washed away.

When the scientists took a closer look at the peculiar tadpoles and their adult forms, using a powerful combination of molecular and morphological data, they realized that they had not only stumbled upon a rare amphibian trait, but had also discovered two brand new species of frogs in the process.

Moreover, the animals turned out so distinct in their evolutionary makeup, compared to all other frogs, that the scientists had to create a whole new genus to accommodate them. Formally named Sumaterana, the genus is to be commonly referred to as Sumatran Cascade Frogs.

“We decided to call the new genus Sumaterana after Sumatra, to reflect the fact that these new species, with their rare evolutionary adaptation are endemic to Sumatra’s rainforests and, in a sense, are emblematic of the exceptional diversity of animals and plants on the island,” says co-author Dr. Utpal Smart. “Tragically, all of them are in peril today, given the current rate of deforestation.“

The authors agree that much more taxonomic work is still needed to determine and describe Sumatra’s herpetofaunal diversity, some of which they fear, could be irreversibly lost well before biologists have the chance to discover it.

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Original source:

Arifin U, Smart U, Hertwig ST, Smith EN, Iskandar DT, Haas A (2018) Molecular phylogenetic analysis of a taxonomically unstable ranid from Sumatra, Indonesia, reveals a new genus with gastromyzophorous tadpoles and two new species. Zoosystematics and Evolution 94(1): 163-193. https://doi.org/10.3897/zse.94.22120

Life in marine driftwood: The case of driftwood specialist talitrids

Driftwood in the sea – either floating or stranded on beaches – is a common feature particularly in temperate regions. Large quantities of driftwood, termed driftwood depositories, may collect at the mouth of small streams associated with marshes and have been present for some 120 millennia – since the origin of flowering plants.

Once marine driftwood begins to decay, it undergoes a specific succession. Firstly, it is colonized by salt tolerant, wood degrading fungi and bacteria, along with a few invertebrates able to digest wood by producing native wood degrading enzymes. The latter include gribbles (isopods) and chelurid amphipods.

Driftwood hoppers (talitrids), as well as isopods, chilopods, insect larvae, some ants and termites, comprize the secondary colonizers. They are all characterized by their inability to utilize driftwood directly. Instead, they rely on symbiotic microflora for digestive purposes.

Within all talitrids, the driftwood hoppers count as few as seven species, most likely because they are extremely difficult to locate and, therefore, discover and describe. Apart from living in tiny burrows, they measure between 13 and <6 mm, which makes the latter the smallest known talitrid.

Having reviewed the driftwood specialized talitrids, Dr. David Wildish of the St. Andrews Biological Station, Canada, concludes that all seven known species demonstrate dwarfism based on slow metabolism and growth. Their sexual development begins earlier compared to faster growing related species. All of them are also characterized with reduced eye size and absence of dorsal pigment patterns.

In his review article published in the open access journal Zoosystematics and Evolution, the scientist confirms that dwarfism in driftwood hoppers has evolved due to poor diet, in turn resulting in slowed metabolism and growth. A further adaptive challenge is the empty gribble burrow size occupied by talitrids (burrow diameter between 0.6 to 5 mm) with the smaller ones being more widespread. Larger talitrids can only complete their life cycle in the larger burrows.

“The size gradient in gribble burrow diameter provides a satisfactory explanation for serial dwarfism within the driftwood talitrids and is why each species becomes successively smaller,” explains the researcher.

Responsibility for first establishing the driftwood talitrid ecological grouping was made during graduate studies by David Wildish, London University, U.K., and Laura Pavesi, University of Rome, Italy. The two criteria for inclusion of a talitrid in the driftwood grouping was: behavioral fidelity to the occupied driftwood and that the food source was solely rotting driftwood (see references).

The larger talitrid family are small/medium in body length (< 30 mm) crustaceans with more than 400 species described in the world list. Ecological groupings within the family include marine/estuarine supralittoral wrack generalists, sand-burrowing, marsh-living and driftwood specialists. A few freshwater and many terrestrial species are also known.

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Original source:

Wildish DJ (2017) Evolutionary ecology of driftwood talitrids: a review. Zoosystematics and Evolution 93(2): 353-361. https://doi.org/10.3897/zse.93.12582