Tag: fish

The Ghibli fish: new ‘painted’ species named after Princess Mononoke

The deepwater tilefish was first spotted by researchers on an online seafood market.

Picture in your mind the discovery of a new species.

What do you see? Researchers cutting through dense, untouched rainforests? Perhaps a submarine plunging into a deep-sea trench, illuminating a new world?

Well, it’s not always quite so dramatic. In fact, researchers in China discovered Branchiostegus sanae when they were scrolling through online seafood markets and noticed some deepwater tilefish with unique cheek patterns.

A tilefish with red and white facial markings. — *Branchiostegus sanae*. Credit: Huang et al.

These red-and-white facial markings reminded the research team of the Studio Ghibli character San from Princess Mononoke, whom they chose to honour in their naming of the species.

Published in the open-access journal ZooKeys, Branchiostegus sanae is a deepwater tilefish belonging to the family Branchiostegidae. Researchers confirmed its new-species status using genetic analysis, and chose “sanae” as the specific epithet (that’s the part that differentiates species within a genus), in a nod to Hayao Miyazaki’s animated creation.

Tilefish with red and white facial markings for sale at a seafood market. — *Branchiostegus sanae* at a seafood market. Credit: Jiangyuan Chen.

“Finding a new species in this group is a rare and fortunate event, especially one as distinctive as Branchiostegus sanae.

“In Princess Mononoke, San is a young woman raised by wolves after being abandoned by her human parents. She sees herself as a part of the forest and fights to protect it. The film delves into the complex relationship between humans and nature, promoting a message of harmonious coexistence between the two: something we hope to echo through this naming.”
Lead author, Haochen Huang.

The Chinese fishermen who sell the new-to-science species call it the“鬼马头鱼” (ghost horsehead fish), and this also contributed to the species name because, fittingly, “Mononoke” (もののけ) refers to supernatural spirits in Japanese folklore.

San, a warrior princess, from the animated film Princess Mononoke holding a spear. — San from *Princess Mononoke*. Credit: © 1997 Hayao Miyazaki/Studio Ghibli, ND.

As their name suggests, deepwater tilefish are found at great depths, with some species found 600 m below the surface. They are important food fish, commonly found in seafood markets in East and Southeast Asia.

Branchiostegus sanae is far from the only new species discovered at a seafood market. Indeed, a new giant isopod was recently dicovered in the same way – and also recieved a pop-culture inspired name. Check it out below!

The Dark Side of the ocean: New giant sea bug species named after Darth Vader

So far only 31 species are described in the family Branchiostegidae, and 19 species in the genus Branchiostegus. From 1990 to 2024, only three new species of Branchiostegus have been described.

Five tilefish species in a grid. — Other species of the genus *Branchiostegus* found in Chinese waters. Credit: Huang et al.

The study, led by researchers from the South China Sea Institute of Oceanology, Chinese Academy of Science, Zhejiang University and Ocean University of China, involved a combination of morphological analysis and genetic sequencing. Specimens were deposited in prestigious marine biological collections in China to facilitate future research.

Original study

Huang H, Chen J, Ke Z, Zhang C (2025) Branchiostegus sanae, a new species of deepwater tilefish (Eupercaria, Branchiostegidae) from the South China Sea. ZooKeys 1227: 129–142. https://doi.org/10.3897/zookeys.1227.130512

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The human dimensions of biological invasions – involving stakeholders in addressing invasive species

Can the knowledge and experience of recreational anglers in Iceland help us understand how far the invasive flounder has spread in the country?

Guest blog post by Theresa Henke

For centuries, all kinds of species have been transported by humans around the globe, allowing them to cross the boundaries of their native range and settle in new ecosystems. Over the past decades the numbers of these introduced species and the impacts they cause have been continuously increasing. Biological invasions nowadays represent one of the biggest threats to biodiversity worldwide.

Humans are and have always been an essential part of biological invasions and in order to fully understand the issue and how to tackle it, we need to understand and include the human dimensions in our research.

My research on European flounder in Iceland began in 2017 when I was writing my Master’s thesis. The flounder is a flatfish species that had been officially documented in the country since 1999 but not much was known on its impacts. In my thesis I looked at the flounder through ecological lenses, trying to identify how the presence of the flounder affects other species. Living in a small community in the Westfjords of Iceland during this time, I got to meet many local people who shared their personal stories, experiences and knowledge with me in every-day conversations. I truly enjoyed these conversations and learning about the species I study from different perspectives beyond the academic settings. These exchanges sparked my interest in exploring the human dimensions of biological invasions and, looking back, have really shaped my academic path going forward.

In our recently published NeoBiota study “Have you seen this fish? – Important contribution of stakeholder observations in documenting the distribution and spread of an alien fish species in Iceland” we wanted to explore how the knowledge and experience of recreational anglers in Iceland can help us understand how far the flounder has spread in Iceland. The flounder in Iceland had only received little scientific interest before and the available information was limited and scattered between different institutions and scientists. Recreational anglers, on the other hand, who chase after native salmon, trout, and char in the Icelandic rivers and lakes, often encounter the flounder.

In 2019, we asked anglers in Iceland to take part in an online survey, where we asked them different questions about the flounder, including where in Iceland they have seen or caught it. We then compared locations named by anglers to the locations that were available from different databases of the Marine and Freshwater Research Institute of Iceland. The locations we received included data collected during scientific surveys and research projects done by the institute as well as observations that were reported to the institute by the public (mostly recreational anglers and commercial fishermen).

Our goal was to evaluate whether observations made by stakeholders, in this case the recreational angling community in Iceland, could be a good source of additional information for monitoring of an alien fish species. Collecting information on the distribution and spread of an alien species is a very important step in addressing biological invasions but is often underdeveloped because not enough resources (i.e. money, time, scientists…) are made available.

Theresa Henke holding a 43-cm flounder in Eyjafjörður.

We have shown that neither source offers a perfect solution to the monitoring of the flounder in Iceland. But we show that each of the sources has their own advantages and disadvantages and by combining them, we are able to get a much clearer picture of where in Iceland the flounder currently occurs and how fast it spread in the early years. Information that was shared by stakeholders, whether it was in our study or to the databases of the Marine and Freshwater Research Institute, played a big role in better understanding the flounder in Iceland.

The interactions with the recreational angling community in Iceland during my PhD have taught me a lot about the flounder in Iceland but even more about my own approach to science. I think as scientists, we should more often take a step outside of our academic bubble and take a look at the issue we are studying from the perspectives of the public and other stakeholders. In the case of biological invasions, we can learn a lot from those who are directly confronted by an invasive species, regardless of whether they have a scientific degree or not.

Research article:

Henke T, Bárðarson H, Thorlacius M, Ólafsdóttir GA (2025) Have you seen this fish? Important contribution of stakeholder observations in documenting the distribution and spread of an alien fish species in Iceland. NeoBiota 97: 67-90. https://doi.org/10.3897/neobiota.97.132365

New ‘grumpy’ fish species discovered in the Red Sea

Found among coral reefs in the Red Sea, it has large canines and a fierce expression, even though it is only 2 cm long.

A team of researchers at the King Abdullah University of Science and Technology and the University of Washington has discovered a new species of fish that seems perpetually displeased. The researchers decided to call this new species the grumpy dwarfgoby.

Despite its small size of less than 2 centimeters, the grumpy dwarfgoby has a surprisingly menacing appearance. Its large canines and fierce expression give it a rather intimidating look for such a small fish.

Lucía Pombo-Ayora, who gave the species its grumpy common name, comments on its distinctive appearance: “I imagine in its own tiny world, it is a fearsome predator. Its grumpy expression and large canines certainly make it look the part, despite its small size.”

A CT scan image of the skull of a grumpy-looking fish.

The species’ bright red coloration actually helps it blend into its natural habitat. It can be found on the walls and overhangs of coral reefs, covered in red coralline algae. There, it lives in small holes and crevices, using its large canines to capture tiny invertebrates. The grumpy dwarfgoby appears to be a relatively rare species, which is likely why it remained undiscovered until now.

The researchers found the first specimens in the Farasan Banks in Saudi Arabia, with additional specimens later found near Thuwal in the Red Sea. It was researcher Viktor Nunes Peinemann who first found it during a diving expedition to explore the coral reef fish diversity. Initially, the researchers thought they had rediscovered the fiery dwarfgoby, Sueviota pyrios, which is only known from a single specimen collected in 1972. However, upon closer examination, they realized they were dealing with an entirely new, undescribed species.

A photograph of a translucent-red grumpy-looking fish on a black background.

“The ongoing discovery of distinctive new species like this grumpy dwarfgoby shows how much biodiversity remains undiscovered in the Red Sea,” Viktor Nunes Peinemann explains. “This is concerning given the recent environmental changes in the region. In some cases, species could go extinct before we even describe them.”

The region is known for its high levels of endemic species and the Grumpy dwarf goby is another addition to this unique fauna. Much of the Red Sea has experienced major disturbances resulting from climate change in recent years, including widespread coral bleaching and mortality. The fact that new species are still being discovered in this rapidly changing environment highlights the urgency of continued research and conservation efforts, the researchers believe.

They have published their discovery in the open-access scientific journal ZooKeys.

Photos by Viktor Nunes Peinemann

Research article:

Nunes Peinemann V, Pombo-Ayora L, Tornabene L, Berumen ML (2024) The Grumpy dwarfgoby, a new species of Sueviota (Teleostei, Gobiidae) from the Red Sea. ZooKeys 1212: 17-28. https://doi.org/10.3897/zookeys.1212.121135

New species, old threats: two hillstream suck-loaches discovered in China

The new-to-science fish face an uncertain future due to pollution and unsustainable harvesting.

All too often, researchers discover new species only to learn they are already at risk of extinction.

So when researchers from Shanghai Ocean University and Yunnan Agricultural University identified two new species from the upper Pearl River system in southwest China, they were likely unsurprised to find the fish facing major threats from pollution and overharvesting.

Three views of a flat-bottomed fish species with bumps on its head. — *Beaufortia* *granulopinna* holotype from Lizhou River, a stream tributary of Bo′ai River of the Pearl River basin, at Tianlin County, Guangxi Province, China.

The new species, Beaufortia granulopinna and Beaufortia viridis, are members of the family Gastromyzontidae, also known as hillstream suck-loaches. They are highly specialised, with compressed bodies, flattened bottoms, and greatly expanded paired fins forming suction cup-like structures. These adaptations enable them to adhere to rocky substrates, resisting currents while feeding on algae and invertebrates.

Researchers discovered the new species during surveys studying aquatic life in various waterways in Yunnan and Guangxi between 2022 and 2024. The study, led by Jing-Chen Chen, offers new insights into the taxonomy and molecular phylogeny of the Beaufortia pingi species group, of which the two discoveries are likely members.

Three views of a flat-bottomed fish species witha green and brown colouration. — *Beaufortia* *viridis* holotype from Wuming River, a stream tributary to the You River of the Pearl River basin, at Wuming District, Nanning City, Guangxi Province, China.

Although research on the Beaufortia pingi group is mostly in its initial stages, the situation is far from optimistic. These species have become popular ornamental fish in China, and aquarium trade operators reap substantial profits through their capture and sale. Among them are those who act with disregard for sustainability, using destructive harvesting practices.

Given the loaches’ preference for fast-flowing water, projects that obstruct rivers can easily lead to regional extinction. Their low pollution tolerance and sensitivity to changes in water quality also contribute to the significant reductions in population that many species are suffering.

Landscape image of a river and trees. — Collection site of *Beaufortia* *viridis* from Wuming River, a stream tributary to the You River of the Pearl River basin, Wuming District, Nanning City, Guangxi Province, China. Photographed by Jing-Chen Chen.

In the habitat of B. viridis, Wuming District, Nanning City, most small tributaries have been modified into step-like reservoirs for water storage, and those near agricultural irrigation areas are polluted, rendering these areas unsuitable for their survival. Interestingly, however, a stable population was discovered inside a commercial eco-camping site left untouched to satisfy consumers’ pursuit of “pristine nature.”

The researchers suggest that future efforts should focus on increasing attention to these species, conducting fundamental research, and further exploring their scientific and economic potential. Simultaneously, it is crucial to enhance habitat conservation awareness, scientifically plan, and develop sustainably, ensuring harmonious coexistence between humans and nature.

Original source

Chen J-C, Li J-J, Tang W-Q, Pu X-R, Lei H-T (2024) Taxonomic resolution of the hillstream suck-loach Beaufortia pingi species group (Cypriniformes, Gastromyzontidae) and two new species from Southwest China– Beaufortia granulopinna and Beaufortia viridis. Zoosystematics and Evolution 100(3): 941-963. https://doi.org/10.3897/zse.100.124370

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Microplastic contamination of Black Sea fish threatens marine ecosystems

Five commercially important fish species from the Bulgarian Black Sea coast were found to be contaminated with microplastics.

Guest blog post by Stephany Toschkova, Sevginar Ibryamova, Darina Ch. Bachvarova, Teodora Koynova, Elitca Stanachkova, Radoslav Ivanov, Nikolay Natchev, Tsveteslava Ignatova-Ivanova

One of the main problems of the world’s oceans, reported by many scientific studies, is microplastic pollution. It is also one of the main sources of pollution in the Black Sea. Our new study in BioRisk details microplastic contamination in five fish species important for commercial fishing (Garfish, Мullet, Knout goby, Pontic shad, and Mediterranean horse mackerel). The fish were collected from the Sozopol area of the Bulgarian Black Sea coast.

Mediterranean horse mackerel. Photo by Donald Davesne
Knout Goby. Photo by Aleksandr_Levon
Мullet. Photo by Roberto Pillon

Our results show a wide variety of micropollutants originating from commonly used items such as plastic cups, stirrers, bags, soft drink bottles, fishing nets, packaging, аnd personal hygiene products. These objects systematically enter the Black Sea and degrade into microplastic particles. Microplastics (MPs) were found in all studied tissues of the fish in the form of pellets, fibers and fragments. Pellets were found most frequently, followed by irregularly shaped fragments, while fibers were the least numerous.

Stereomicroscope picture of morphological types of microplastics (arrowheads) recognized in the studied specied from: A) Garfish; B) Mullet C) Pontic shad and D) Mediterranean horse mackerel.

The bulk of the isolated plastics are made of polyethylene (PE) and polyethylene terephthalate (PET). PE is found in plastic bottles, cups, stirrers, and plastic bags. This polymer is very light and floats on the surface of the sea because its density is lower than that of water. PET, on the other hand, is denser than water and more likely to sink and accumulate in it and in organisms living on the seafloor. These polymers are widely used in fabrics, nets, ropes, and strings used for fishing, one of the main economic activities in the Black Sea. The predominant polymer type, PE, corresponds to the content of manufactured plastics all around Europe, as almost half of the plastics produced in Europe are reported as PE.

The sinking and sedimentation of plastics relate to the fact that the upper layer of the Black Sea is less dense than that of other seas. Furthermore, the weight of these particles increases due to the accumulation of marine plants and nutrients on them, and this can affect the distribution of plastics and their sedimentation on the seabed.

A satellite image of the Black Sea. Photo by NASA/GSFC/MODIS

Judging by the obtained results and the amount and type of polymers found in the study and the literature, the source of contamination, in our opinion, can be mainly attributed to domestic wastewater discharges coming from the washing of synthetic fabrics. In Bulgaria, wastewater is discharged – directly or after purification – into marine and freshwater ecosystems, as is the case in other neighbouring countries along the Black Sea coast. However, detailed studies are needed to prove this hypothesis.

Considering the wide variety of MP types detected in the digestive tracts of the fish, we assume that they regularly ingested MPs during feeding. Many nutrients are also held on the plastic particles, which deceives the fish into perceiving them as food.

microplastics under a microscope — Microplastics under a microscope. Photos by GTM NERR

Microplastics under a microscope. Photos by GTM NERR

It has been reported that plastics smaller than 1000 μm can reach the digestive tract or the gills of fish, and in turn can cause adverse effects such as a weak immune response or reduced fertility.

MPs can also accumulate in predatory fish species. Unfortunately, very limited research was performed on bioaccumulation and biomagnification in food webs, therefore more studies are needed to reach this conclusion.

MPs enter seawater food chains in different pathways and threaten entire ecosystems through their ability to transport pollutants, pathogenic microorganisms, and alien species. Bearing in mind the intensifying economic activity on the Black Sea coast and the consequent influence on the riverine water quality, river mouths can be considered potential sources of MPs. Particularly concerning is the area near the Kamchia River mouth, which is the biggest intra-territorial river in Bulgaria, entering directly into the Black Sea, with a catchment area of more than 5 300 km². This catchment and the entire Black Sea coast, where agriculture is well developed is a potential source of MPs, which have the ability to absorb and release toxic chemicals of organic and inorganic origin such as bisphenol A, PCBs and DDT, creating an additional potential risk to human health.

A satellite image showing the Kamchia River mouth.

Humans are exposed to BPA in the environment they live in, from the air we breathe to the food and drinks we consume. So, even if BPA intake is below accepted limits, this does not guarantee that the additive will not accumulate and cause more pronounced effects and chronic toxicity in the food chain, given its tendency to accumulate.

It is important that future research determines the toxicological side effects of plastic ingestion for fish communities in both benthic and pelagic habitats. However, even if we stop introducing plastics into the water system, both groups of fish will continue to be impacted, since the number of microplastics can increase due to the breakdown of larger plastics in the environment.

Invasive species as biomonitors of microplastics in freshwater ecosystems?

This study shows the need to carry out further studies of microplastics using different types of microscopic and spectral analysis. Even though microplastics may not pose a risk to humans who consume fish, these contaminants pose a potential risk to marine food webs and endangered species. We found particles of different sizes, types and colours in different fish species, and believe the variability of polymer types in fish can indicate the polymer types in water to some extent. Our results show that fish are important as ecological bioindicators and serve as a basis for future studies on microplastic pollution in tourist sandy beaches.

Research article:

Toschkova S, Ibryamova S, Bachvarova DCh, Koynova T, Stanachkova E, Ivanov R, Natchev N, Ignatova-Ivanova T (2024) The assessment of the bioaccumulation of microplastics in key fish species from the Bulgarian aquatory of the Black Sea. BioRisk 22: 17-31. https://doi.org/10.3897/biorisk.22.117668

Fourteen years after the Gulf of Mexico oil spill, endemic fishes face an uncertain future

A study investigating the spill’s impact on endemic fish species suggests potential loss of biodiversity.

The 2010 Gulf of Mexico Deepwater Horizon was the largest accidental oil spill in history. With almost 100 million gallons (379 million liters) of oil combined with dispersants suggested to remain in the Gulf, it is one of the worst pollution events ever. More than a decade later, its long-term effects are still not fully understood.

A ship sails among spilled oil in the Gulf of Mexico after the BP Deepwater Horizon oilspill disaster. Photo by Kris Krug shared under a CC BY-NC-SA 2.0 license.

In a new study, researchers from Louisiana State University and Tulane University examined the endemic Gulf of Mexico fish species that may have been most impacted by the oil spill to see how their distribution has changed over the years. To get their data, they studied museum specimens from natural history collections, looked at relevant literature, and combed biodiversity databases.

Lead author Prosanta Chakrabarty in the fish collections of the Louisiana State University Museum of Natural Science, where many specimens from the Gulf of Mexico are housed. — Lead author Prosanta Chakrabarty in the fish collections of the Louisiana State University Museum of Natural Science where many specimens from the Gulf of Mexico are housed. Photo credit: Eddy Perez, LSU

With 1541 fish species known from the region, and 78 endemic fish species, the Gulf of Mexico is one of the most biologically rich and resilient marine environments in the world, but how much of this diversity is still left intact?

The study found that 29 out of the Gulf’s 78 endemic fish species haven’t been reported in museum collections since 2010. The Yucatan killifish, for example, which is considered endangered, was last reported pre-spill, in 2005, off the Yucatán Peninsula.

Six of the non-reported species are considered of greatest concern, because their areas of distribution largely overlap with the affected area – although the authors note that their absence in the Gulf in recent years cannot automatically be attributed to the oil spill.

Jars of voucher specimens of fishes at the Louisiana State University Museum of Natural Science. Photo credit: Eddy Perez, LSU

“Understanding the impacts of catastrophic environmental events such as the 2010 Gulf of Mexico Oil Spill does not end when the wellhead is capped or when the last drops of oil cease to flow. The disaster only begins to end when the data no longer show impacts of the event. We are far from the beginning of the end for the Deepwater Horizon Oil Spill. Lingering chemicals, lost generations of wildlife and a continued ecosystem imbalance may all be factors that prevent an environment from rebounding from such cataclysmic events,” the authors note in their research article.

However, they also point out that nature’s ability to recover should not be overlooked.

“The Gulf of Mexico continues to face many challenges, from the Dead Zone, to climate change, loss of coast habitats and continued oil spills. Efforts like this report aim to bring attention to vulnerable species that continue to be impacted by human activities and to the unique endemic fauna of the region,” the researchers write in conclusion.

Research article:

Chakrabarty P, Sheehy AJ, Clute X, Cruz SB, Ballengée B (2024) Ten years later: An update on the status of collections of endemic Gulf of Mexico fishes put at risk by the 2010 Oil Spill. Biodiversity Data Journal 12: e113399. https://doi.org/10.3897/BDJ.12.e113399

NOAA Fisheries Zoologist Describes New Fish Species

Dr. Katherine Bemis of the National Systematics Laboratory recently helped describe a new species of fish, the papillated redbait.

New species alert! Dr. Katherine Bemis of NOAA Fisheries’ National Systematics Laboratory and her collaborators recently described a new fish species: Emmelichthys papillatus, or the papillated redbait. Its discovery was published in the journal ZooKeys.

The papillated redbait is a member of the family Emmelichthyidae. There are only 18 known species in this family, which are commonly called redbaits, rovers, or rubyfishes. These deepwater species can be found in warm, tropical waters and are usually bright shades of red, orange, and pink.

How did Bemis and her team make this remarkable discovery? To find out, we’ll have to first travel to a fish market in the Philippines.

A molecular mystery

As part of an interagency campaign to create a reference library of fish DNA “barcodes,” Bemis and her colleagues regularly travel abroad to collect fish specimens. Some come from seafood markets overseas where they are being sold for food. In the field, these new specimens are assigned a preliminary species identification. Then, they’re transported to the Smithsonian Institution and National Systematics Laboratory for genetic sequencing, data collection, and a secondary species confirmation.

Dr. Katherine Bemis holds the holotype–the specimen upon which a new species’ description is based–of the papillated redbait. Credit: Haley Randall/NOAA Fisheries

Since getting involved with this project in 2021, Bemis and teammate Dr. Matthew Girard of the Smithsonian National Museum of Natural History have analyzed thousands of samples. None have made a bigger splash, though, than two small pink fish collected from a Philippine fish market on the island of Cebu.

While collecting data from these specimens, Girard made an exciting observation. Their genetic sequences did not match their initial species identification as golden redbaits—or any other species in the genetic library, for that matter. So which species did Girard and Bemis have on their hands?

Dr. Matthew Girard examines the holotype of the papillated redbait under a microscope. Credit: Dr. Katherine Bemis. Source NOAA Fisheries

In search of answers, Bemis and Girard examined other aspects of the specimens’ biology, including their anatomy. They discovered that these fish differed from the golden redbait in several ways, including:

A different number of gill rakers, structures inside the mouth that help fish to feed
A different number of pectoral fin rays
Two fleshy structures called papillae on the pectoral girdle

These differences, combined with the genetic data, provided evidence that the two specimens were not golden redbaits, but a previously undiscovered species. With only two confirmed specimens, Bemis and Girard wondered if other individuals could be identified in global natural history collections.

Underneath the gill cover, you can observe the two characteristic papillae (singular: papilla) of the papillated redbait labeled with arrows (left). The closely-related golden redbait lacks papillae in the same area (right). Photos courtesy of Dr. Matthew Girard. Source NOAA Fisheries

After some detective work, Bemis and Girard spotted a third specimen they hypothesized might also be the undescribed species. A fish with similar color also identified as a golden redbait had been collected from a fish market in the Philippines by the Kagoshima University Museum in Japan. Bemis and Girard studied the specimen and confirmed their hypothesis with genetic and anatomical data. This specimen became the third record of papillated redbait and, ultimately, the holotype for the species—the specimen upon which a new species description is based.

More to discover

Even after describing new species, there’s always more to learn. Bemis and Girard are energized that there is still much to discover about the papillated redbait and the redbait family, which is relatively poorly known. Any opportunity to add to this small body of knowledge and study redbait species in greater detail is valuable. “I’ve had researchers that work on fish taxonomy say to me, ‘I didn’t even know this family existed.’ That’s how little we know about this group,” Girard emphasizes.

Bemis also notes that because data on the papillated redbait comes from only three specimens purchased in fish markets, she still has lots of questions. For example, Bemis says that they don’t yet know if the new species occurs outside Philippine waters, or the exact habitat in which they occur. “We also don’t know anything about their reproduction or what they eat—really basic aspects of their biology remain to be studied. Now that we recognize that it is different, we only have more to study as new specimens of papillated redbait are collected,” Bemis says.

“It is always a happy and productive moment working with U.S. scientists,” says Dr. Mudjekeewis “Mudjie” Santos of the Philippine National Fisheries Research and Development Institute. Santos was instrumental in the collection of specimens, providing fisheries data on the papillated redbait, and coining a name for the new species in Tagalog, the national language of the Philippines. Here, he examines fish in a Philippine market. Photo courtesy of Dr. Mudjekeewis Santos. Source NOAA Fisheries

One thing is for certain, though. There are more species just waiting to be discovered, and they might be right under our noses. “I think the craziest thing is that the papillated redbait is a new species that came from a market,” Girard says. “The fact that there are undescribed species being sold without us even realizing it underscores how much we still have to learn about marine biodiversity.”

Research article:

Girard MG, Santos MD, Bemis KE (2024) New species of redbait from the Philippines (Teleostei, Emmelichthyidae, Emmelichthys). ZooKeys 1196: 95-109. https://doi.org/10.3897/zookeys.1196.111161

This story was originally published by NOAA Fisheries. It is republished here with their permission.

AI-powered data-limited stock assessment method more accurate than ‘gold standard’ in predicting sustainable fisheries catches

A recent update introduced to the CMSY methodology used to assess the status of fish stocks has proven to more accurately predict the catch that a population can support than highly valued data-intensive models.

Article provided by Valentina Ruiz, Sea Around Us.

In a paper published in the journal Acta Ichthyologica et Piscatoria, the international team of researchers that shaped the improved CMSY++ model noted that its results better correspond with what is, in reality, the highest catch that a fish stock can support in the long-term, given that environmental conditions do not change much.

Now powered by an artificial neural network that has been trained with catch and biomass data of 400 stocks to identify plausible ranges of the initial and final state of the stocks being assessed, CMSY++ allows managers and scientists to input only catch data to estimate how much fish is left in a given stock and how much fishing pressure can be applied.

CMSY model — Schematic representation of the surplus production model used by CMSY, with indication of impaired recruitment due to small stock size, where FMSY is reduced linearly with decline in biomass.

Maximum sustainable catches or yield (MSY) is a concept developed in the 1950s by US fisheries scientist M.B. Schaefer who proposed that if fishers left in the water a biomass equivalent to at least 50 per cent of the unexploited fish population, that is, of the biomass it had before being commercially exploited, then the highest possible catches could be sustained over time.

“By comparing the results of CMSY++ to models that are considered superior because they require large amounts of initial data inputs, such as the Fox surplus-production model and the Stock Synthesis (SS3) age-structured model, we noticed that these models badly overpredicted the catch that a population can support when previous overfishing has reduced it to a small fraction of its natural size, as is the case with most exploited fish populations in the world.”
Dr. Rainer Froese, lead author of the study and a senior scientist at the GEOMAR Helmholtz Centre for Ocean Research.

In other words, the model underlying the CMSY++ method fitted the observed data, while the predictions of the ‘gold standard’ models were too optimistic in estimating sustainable catches.

“These models tend to estimate the biomass required to produce maximum sustainable yields as less than half of unexploited biomass, which is lower than M.B. Schaefer originally proposed based on the widely observed S-shaped growth curve of unexploited populations or population size that the ecosystem would normally accommodate.

“This finding could explain the often-observed failure of fisheries managers to maintain or rebuild depleted stocks even when the predictions of the gold standard models were followed.”
Daniel Pauly, co-author of the study and principal investigator of the Sea Around Us initiative at the University of British Columbia.

Research article:

Froese R, Winker H, Coro G, Palomares MLD, Tsikliras AC, Dimarchopoulou D, Touloumis K, Demirel N, Vianna GMS, Scarcella G, Schijns R, Liang C, Pauly D (2023) New developments in the analysis of catch time series as the basis for fish stock assessments: The CMSY++ method. Acta Ichthyologica et Piscatoria 53: 173-189. https://doi.org/10.3897/aiep.53.e105910

Seven new species of whitefish described in Central Switzerland

Biologists at Eawag identified whitefish species in the lakes of the Reuss river system. Of them, seven are described as new to science.

Biologists at Eawag have identified ten species of whitefish in the lakes of the Reuss river system. Of these, seven have been described as distinct species for the first time – although in two cases this required inspection of specimens from historical collections, since eutrophication of lakes in the 20th century also led to the extinction of fish species in Central Switzerland.

These seven whitefish were described as separate species for the first time, including the “Albeli” from Lake Lucerne, which now bears the name Coregonus muelleri in memory of the whitefish expert Rudolf Müller. Image by Eawag

The “Edelfisch” (Coregonus nobilis) was, after the smaller “Albeli”, the second most commonly caught species of whitefish in Lake Lucerne until, in the second half of the 20th century, phosphate from domestic wastewater and nutrient-rich run-off from farmland led to a massive increase in algal blooms. Compared to the lakes of the Central Plateau, nutrient levels in Lake Lucerne were moderate, and eutrophication was short-lived; even so, due to algal decomposition, oxygen was depleted in the deeper layers of the lake. The “Edelfisch”, which reproduces in the late summer at a spawning depth of 80 metres or more, suffered as a result. Shortly before nutrient inputs decreased following the ban on phosphates in detergents and the expansion of wastewater treatment plants, stocks of this species collapsed and it was considered to be extinct in 1980. Only from the late 1990s were individual specimens caught once again, unequivocally identified as C. nobilis in 2000 by the whitefish specialist and Eawag researcher Rudolf Müller.

Coregonus nobilis, Lake Lucerne, Switzerland.

Five whitefish species in Lake Lucerne

As the “Edelfisch” is now a protected species, Lake Lucerne has not lost any of its historically recorded whitefish species. Indeed, in addition to the familiar “Edelfisch”, “Albeli” and “Bodenbalchen”, Eawag scientists have identified two new species – two large whitefish, differing from the previously known species in their habits, morphological characteristics and genetic composition. The pelagic “Schwebbalchen” (Coregonus suspensus) probably lives permanently in the open water, not only for foraging but also for reproduction – a spawning behaviour only previously observed in the “Blaufelchen” (C. wartmanni) of Lake Constance. Occupying a position intermediate to the pelagic “Schwebbalchen” (C. suspensus) and the “Bodenbalchen” (C. litoralis) is the littoral “Schwebbalchen” (C. intermundia).

Lake Zug survivor

Particularly affected by eutrophication in the mid-20th century were whitefish in Lake Zug, which – like other Central Plateau lakes – was exposed to higher nutrient levels, for a longer period, than waterbodies further upstream. As only the uppermost water layers of this 200-metre-deep lake maintained oxygen levels sufficient to support fish, two whitefish species spawning in the depths of the lake died out – the (Lake Zug) “Albeli” (C. zugensis) and “Albock” (C. obliterus). Indeed, the Lake Zug “Albock” would have been completely forgotten if specimens had not been found by Eawag scientists Oliver Selz and Ole Seehausen in the historical Steinmann-Eawag Collection. Its morphology and historical accounts indicate that the Lake Zug “Albock” was a deep‑water specialist – a specialisation only otherwise observed to the same degree in the (likewise extinct) Lake Constance Kilch (C. gutturosus) and the (still extant) Lake Thun Kropfer (C. profundus).

The only whitefish species still found in Lake Zug today, spawning near the shore, is the “Balchen”. Testifying to its survival is its new scientific name – Coregonus supersum (“I have survived”).

Species endemic to each lake

Also new are the scientific names of the Lake Lucerne “Bodenbalchen” (C. litoralis) and “Albeli” (C. muelleri). For the morphological and genetic studies carried out by Oliver Selz and Ole Seehausen in order to revise the taxonomy of whitefish showed that almost every lake in Central Switzerland has its own species of “Albeli” and “Bodenbalchen”.

Previously, the “Albeli” of Lakes Zug and Lucerne had been classified as members of the same species (C. zugensis), while the “Balchen” spawning near the shore of the various Central Swiss lakes were known as C. suidteri. These collective species names have now been inherited by the extinct Lake Zug “Albeli” (C. zugensis) and the Lake Sempach “Balchen” (C. suidteri).

The Lake Lucerne “Albeli” received the new name C. muelleri in honour of the fisheries biologist and whitefish specialist Dr Rudolf Müller (1944–2023).

Ruedi Müller with the then Lucerne fisheries and hunting administrator, Josef Muggli, catching whitefish. Photo by Robert Muggli, Archive

A reflection of Switzerland

The lakes of the Reuss river system are a reflection of Switzerland as a whole. Since the last ice age, at least 35 whitefish species evolved in the pre-alpine lakes, usually two or more in each lake. Switzerland lost a third of these species during the period of lake eutrophication around the middle of the 20th century. Many of the lost species are known to researchers only thanks to historical collections, such as that created before the eutrophication period by the naturalist Paul Steinmann and currently curated by the Natural History Museum of Bern.

Original source:

Selz OM, Seehausen O (2023) A taxonomic revision of ten whitefish species from the lakes Lucerne, Sarnen, Sempach and Zug, Switzerland, with descriptions of seven new species (Teleostei, Coregonidae). ZooKeys 1144: 95-169. https://doi.org/10.3897/zookeys.1144.67747

“Oscar describes Oscar”: Interview with Oscar Lasso-Alcalá, Pt 3

“This is why Mikolji’s Oscar is a highly appreciated species in the aquarium hobby. It is more than just a fish in an aquarium when it is considered a true pet.”

In this last part, we talked with ichthyologist Oscar Miguel Lasso-Alcalá about what makes Astronotus mikoljii – a new to science cichlid species that he recently described in ZooKeys – so special.

Find Part 1 and Part 2 of the interview.

What makes this species so charismatic and loved by aquarists and ichthyologists?

I already spoke about my experience as an aquarist from an early age, where the qualities of the species of the Astronotus genus, known as Oscars are highlighted.

Different varieties and color patterns have been obtained from them through selective breeding, or genetic manipulation, which are called living modified organisms (LMOs) or genetically modified organisms (GMOs).

However, the true lovers of nature, the aquarians of the “Biotope Aquarium” movement and the like, prefer pure specimens to manipulated or artificially modified ones. This is why Mikolji’s Oscar is a highly appreciated species in the aquarium hobby. It is more than just a fish in an aquarium since it is considered a true pet.

For ichthyologists, it is remarkably interesting and at the same time very challenging to study a genus like Astronotus, which already has only three described species (Astronotus ocellatus, A. cassiprinnis and A. mikoljii).

This is an unusual situation, which, as we have reported, requires an integrative approach and the work and experience of different specialists for its study. With all certainty, as in the case of Mikolji’s Oscar, other species of the genus Astronotus remain to be studied and described, and we hope that we will have the fortune to participate with our experience in these new works.

Local people have long known this species. What role does it have in their lives?

It is important to clarify that Astronotus mikoljii is a new species for science, but it is not a “new species” for people who already knew it locally under the name of Pavona, Vieja, or Cupaneca in Venezuela or Pavo Real, Carabazú, Mojarra and Mojarra Negra in Colombia. Nor for the aquarium trade, where it was known by the common name of Oscar and scientific name of Astronotus ocellatus, or, to a lesser degree, as Astronotus cassiprinnis.

This species has been of great food importance for thousands of years for at least nine indigenous ethnic groups.

Much less is it a new species for the nine thousand-year-old indigenous ethnic groups that share their world with the habitat of this fish, who baptized it with some 14 different names, known in their languages as mijsho (Kariña), boisikuajaba (Warao), hácho (Pumé = Yaruro), phadeewa, jadaewa (Ye’Kuana = Makiritare), perewa, parawa (Eñepá = Panare), yawirra (Kúrrim = Kurripako), kohukohurimï, kohokohorimï, owënawë kohoromï” (Yanomami = Yanomamï), eba (Puinave), Itapukunda (Kurripako), uan (Tucano).

Hence, the importance of scientific names, since the same species can have multiple common names, in the same language or in multiple languages.

It is important to note that very few studies that describe new species for science include the common names of the species, as given by the indigenous ethnic groups or natives of the regions, where the species live.

This species has been of great food importance for thousands of years for at least nine indigenous ethnic groups, and for more than 500 years to the hundreds of human communities of locals who inhabit the Orinoco River basin in Venezuela and Colombia. In our studies, in the plains of Orinoco from 30 years ago, we were able to verify its consumption, as well as high gastronomic value, due to its pleasant taste and enhanced texture.

However, due to my imprint as an aquarist, I have not wanted to consume it on the different occasions that it was offered to me, because it is very difficult to eat the beloved pets that we had in our childhood.

Why is this fish important to people and to ecosystems?

It is especially important to highlight that the Astronotus mikoljii species plays a very important role in the ecosystem, due to its biological and ecological background.

Although it can feed from different sources, it is a fundamentally carnivorous species, and therefore, it “controls” other species in the ecosystem.

Without Mikolji’s Oscar, the aquatic ecosystem would lose one of its fundamental links and the delicate balance of its functioning, because the species it feeds on could increase their populations uncontrollably, becoming veritable pests. This would put in great danger the entire future of the aquatic ecosystem of the Orinoco River basin and the permanence of other species of ecological importance.

In addition, it would surely affect other species used by man, both those of commercial importance (sold as food or as ornamental species), and for the subsistence fishing of native and indigenous inhabitants.

Mikolji’s Oscar, although a carnivorous species, also has its natural predators, for example piranhas and other predatory fish. For this reason, it evolved with an ocellus, or false eye, at the base of the caudal fin, to confuse its predators and guarantee its survival. Obviously, this species will be compromised if we don’t learn about it, use its populations wisely and preserve it in the long term.

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Photos by Ivan Mikolji.

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You can find Part 1 and Part 2 of the interview with Oscar.

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