40 Of The Most Fascinating Species Discovered In 2023

These days, most news about Earth's biodiversity is a real bummer. For example, a 2022 report published by the World Wildlife Fund found that animal populations across the globe have decreased by a catastrophic 69% between 1970 and 2018, primarily due to human-caused factors like habitat loss and climate change. And things aren't exactly on an upward trend. According to a 2023 study published in Biological Reviews, 48% of over 70,000 animal species surveyed are on a downward trajectory.

Birds, insects, mammals, and amphibians are especially impacted, with continued population declines prompting many biologists to announce the arrival of a sixth mass extinction event – this time due to what the study calls "Anthropocene defaunation," which is a fancy way of saying human activity is responsible for all this destruction. Plants and fungi – the foundation of all life on Earth – are also being lost at alarming rates. As a 2020 report by Kew Royal Botanic Gardens noted, 40% of plant species face extinction. And these are just the ones we know about!

Luckily, it's not all bad news. Scientists estimate that about 10% to 20% of Earth's species remain undiscovered. Diligent biologists working across the globe discover up to 18,000 new species each year, which opens doors for targeted conservation efforts and habitat preservation. From brand-new mammals to carnivorous plants to insects exhibiting previously unseen behaviors, there's plenty of proof that nature can still surprise us. Here are just a few of the most fascinating species discovered in 2023.

Of all the animals impacted by man, amphibians have it the worst. According to a 2017 study published in Climate Change Responses, they are especially susceptible to habitat loss, increased ultraviolet radiation due to ozone depletion, diseases, environmental pollutants, and acid rain – all of which are attributable to human activities. This makes the discovery of a new frog species even more exciting – and critical for its conservation.

The frog in question also happens to be quite a stunner. According to a 2023 study published in ZooKeys, biologists found the frog during a survey of the tropical forests of Río Negro-Sopladora National Park in southern Ecuador's Andes Mountains. They were so taken by the relatively large treefrog's bright colors and speckles that they named it Hyloscirtus tolkieini after renowned fantasy author J.R.R. Tolkien, writing: "The amazing colors of the new species evoke the magnificent creatures that seem to only exist in fantasy worlds."

The species was described based on a single specimen, meaning additional research is needed to determine its conservation status. Luckily, the frog's habitat is safe for the time being, as the over 75,000-acre Río Negro-Sopladora National Park was designated a protected area in 2018. Sticking to the magical theme, one of the study's authors, Diego F. Cisneros-Heredia, said in a statement (via Mongabay): "The truth is that the tropical Andes are true magical ecosystems where some of the most wonderful species of flora, fungi, and fauna in the world are present."

[Featured image by Juan C. Sánchez-Nivicela via Wikimedia Commons | Cropped and scaled | CC-BY-4.0]

In some cases, discovering a new species doesn't even involve leaving the house – or museum, as it were. Plenty of species are hiding out in existing collections and databases, just waiting to be found. As noted in a 2023 study published in the Raffles Bulletin of Zoology, Australian taxonomists found a whole new fish that way – and they didn't even need diving gear or a submarine to do it. After poring over museum specimens, reviewing underwater photographs, and performing some genetic analysis, they discovered that what was originally thought to be a single species of brightly colored dartfish was actually two, one of which hadn't been described before.

Upon closer examination, biologists realized that some fish had completely different colors and markings than the known species, the Helfrich's dartfish. For one, they didn't have a scowly dark mustache. The new species, an adorable little creature sporting a purple crown and bright yellow face, lives in coral reefs in the western and central Pacific Ocean. Due to its striking coloration, biologists named it Nemateleotris lavandula: the lavender-blushed dartfish.

Splitting one species into two has significant conservation implications. "Without careful taxonomy, we would have never known that there were two species hidden under one name," lead researcher Yi-Kai Tea told Newsweek. "Now that we do, we can re-assess their distributions, their statuses, and where to go from here. Putting a name to something is the first and most important step towards conservation. You cannot protect what we don't know exists."

While the name "squat lobster" might not equal "fascinating" in most peoples' minds, these little crustaceans are actually pretty impressive. They are extremely diverse, with many living in the abyssal deep sea, a high-pressure, pitch-black, and generally mysterious realm that occurs 9,842 to 22,325 feet below the surface. Even in modern times, the deep ocean remains largely unstudied due to its extreme inaccessibility. So, how do biologists discover new squat lobsters?

According to a 2023 study published in Invertebrate Systematics, they were collected by the human-operated submersible vehicle, Alvin, famous for exploring the Titanic. Alvin features suction devices and robotic arms, allowing it to gather samples. Amazingly, the creatures were captured alive, enabling biologists to photograph, study, and harvest DNA from them. Overall, the effort resulted in five new species of squat lobster of the genus Munidopsis – including one that was collected way back in 1990.

Squat lobsters are close relatives of hermit crabs named for their tucked-under tails, which give them a compact folded-up shape. They frequently hang out around hydrothermal vents, cold-water reefs, and "whale falls" – or sunken whale carcasses – at great depths. "We still do not know how many species live in our world, especially marine invertebrates living in the deep sea," lead researcher Paula Rodríguez-Flores told Harvard's Museum of Comparative Zoology. "We need to continue to explore the deep ocean, collecting more specimens, to have a complete picture of the distribution range and evolution of animals in the abyss before they disappear."

Note: A different species of Munidopsid squat lobster is pictured.

Sometimes, species remain undiscovered simply because no one goes looking for them. Such was the case when a microbiologist named Breyton Van der Merwe happened upon an unusual white mushroom while on a January stroll in the temperate forests of South Africa. Even wilder? He was just a student at the time. According to a 2023 study published in Mycology, Van der Merwe had found a new species of mushroom in the genus Hericium – only the second such fungus known to exist in Africa.

Researchers named the new mushroom Hericium ophelieae after Arthur Rimbaud's French poem "Ophélie," which depicts the death of Shakespeare's "Hamlet" character Ophelia. Rimbaud's elegiac lines like "long veils," "beautiful as snow," and "white phantom" perfectly described the ghostly mushroom's wispy fruiting body, which grows only on the decaying trunks of a few hardwood tree species in South Africa's Knysna-Amatole forests during the rainy season. And, while that's plenty exciting all on its own, the discovery has even greater implications.

Hericium mushrooms have long been prized for their medicinal and nutritional uses. In fact, one species – the lion's mane mushroom – has been used as both food and traditional medicine in China for centuries. As Breyton Van der Merwe, the researcher credited with discovering the mushroom, told McClatchy News (via Yahoo!): "Several unique medicinal compounds have been described from Hericium species, and these compounds have been used in studies as treatments for everything from neuropsychiatric disorders like depression to cancer, and even anti-aging treatments."

[Featured image by T. Conradie and B. Van der Merwe via Mycology | Cropped and scaled | CC BY 4.0 ]

Some of the coolest new species are found completely by accident. While studying a different species of spider in Madagascar, researchers happened upon a bizarre scene: a bunch of male spiders sharing a web and hanging out together. According to their 2023 study published in Insect Systematics and Diversity, the researchers first spotted the spider gatherings from a moving car and immediately jumped out to investigate.

The gregarious arachnids turned out to be a type of box kite spider, which are small web-spinning spiders known for their square backs, bright colors, and spiny protuberances. And not only were they a new species – Isoxya manangona – but their behavior was totally unusual for spiders. The researchers observed 22 different "colonies," each featuring up to 21 individual female webs connected like a spider sorority. In the middle of the network was a single line of web, on which up to 38 males perched together.

Even stranger, the males weren't being aggressive toward each other – something practically unheard of in the spider world, which is typically solitary at best, and, at worst, cannibalistic. In fact, out of around 50,000 known spider species, less than 0.1% are social. Researchers believe that the unusual behavior is a form of lekking, in which male animals gather to display for females. If proven, this will be the first time lekking has ever been documented in spiders. As lead researcher Igni Agnarsson told Entomology Today: "Further research is necessary but is bound to find something fascinating."

Note: A different species of box kite spider is pictured.

What's even more fascinating than carnivorous plants? New-to-science carnivorous plants. And there's good news: botanists have found not one but two new species of butterwort! According to a 2023 study published in PhytoKeys, both species were discovered high in the tropical Andes Mountains of southern Ecuador. One, Pinguicula jimburensis, lives on the marshy shores of a highland lagoon while the other, Pinguicula ombrophila (pictured), lives on steep limestone cliff faces.

Unlike most plants, butterworts thrive in harsh environments with nutrient-poor soil. For these plants, it's "no nutrients, no problem" as they extract everything they need from their insect prey, which they trap on their sticky basal leaves. They also produce attractive two-lipped flowers on raised stalks, which have made a few species popular in the horticultural trade. Both new butterwort species rely on wet environments, deriving moisture from rainfall and fog. In fact, one of them – Pinguicula ombrophila – is even named for it, with its specific epithet "ombrophila" translating to "rain-loving" in Latin.

Because of this – and the fact that each is known from only a single location – both species are more sensitive to environmental disturbance, habitat loss, and climate change and are already considered at risk of extinction. "Even in well-known groups such as the carnivorous plants, new taxa are continuously discovered and described, in particular from remote areas that become accessible in the course of the unlimited urban sprawl," the researchers wrote in the study. "This is both encouraging and worrying at the same time."

[Featured image by Álvaro J. Pérez via PhytoKeys | Cropped and scaled | CC BY 4.0 ]

Typically, far fewer vertebrates are discovered each year than, say, insects or plants. But geckos are the exception. In fact, 28 new geckos were described in a single paper in 2022. While many gecko species have already been discovered in 2023, this one might just be the most fascinating because, well, it can fly – kind of. As announced in a 2023 study published in Salamandra, researchers found a new species of parachute gecko in the Indian state of Mizoram.

Like others in this unique lizard group, which are also called flying geckos, Gekko mizoramensis is a nocturnal lizard that uses flaps of body skin to "fall with style" – sometimes for distances of up to 200 feet – to both escape predators and glide from tree to tree in its tropical forest home. At around 8 inches long, it's pretty noticeable – especially when it ventures into urban areas and lands on the side of buildings.

As is often the case in nature, the new gecko hid in plain sight for years because it looked nearly identical to another flying gecko, making it what biologists call a "cryptic species." But, after analyzing the lizard's DNA, researchers confirmed that it was genetically distinct. Because its full range is still unknown, protecting what could be a rare species is vital. "There is a lot of superstition and mythological belief in Mizoram," lead researcher Hmar Tlawmte Lalremsanga told India Today. "The people here usually hunt so it is very important to spread awareness."

Note: A different species of parachute gecko is pictured.

On occasion, researchers set out to study one species only to discover a totally different one in the process. Such was the case when biologists searching for a critically endangered tree toad in the Ukaguru Mountains of central Tanzania stumbled upon a mysterious little golden frog instead. Even wilder? It was a brand-new species – and an unusual one at that.

According to a 2023 study published in PLOS ONE, this species doesn't croak or call like most other frogs. Rather, males likely attract mates with a series of small spines on their throats, which researchers believe the frogs use as a kind of Braille. As a result, the media took to calling it the "silent frog," though its official name is Hyperolius ukaguruensis. It can be distinguished from other spiny-throated reed frogs by its golden coloration, genetics, and relatively small eyes.

The Ukaguru Mountains are considered "sky islands" – a type of biological hotspot in which one ecosystem is surrounded by a radically different habitat type, isolating the species that live there. The tropical rainforest mountaintops, therefore, become like islands in a sea of savanna, giving rise to unusual species found nowhere else on Earth. "The Ukaguru Mountains are part of the greater Eastern Arc Rift, a fascinating cradle of biodiversity, with many species endemic to single mountain blocks," study researcher H. Christoph Liedtke said in a press release. "The fast population growth in Tanzania means that the mountain forest habitats are under growing threats from people."

[Featured image by C. Liedtke via PLOS ONE | Cropped and scaled | CC BY 4.0 ]

While describing new species is important for conservation, sometimes it can also expose previously anonymous lifeforms to new dangers. And, for one botanist, this created a bit of a quandary. According to a 2023 study published in Madroño, botanist Stephen McCabe discovered two new plant species – Dudleya delgadilloi and Dudleya cochimiana (pictured) – while surveying Isla Cedros, a small island off the coast of Baja California, Mexico.

Both new species are members of the western North American genus Dudleya, which are commonly known as liveforevers. As their name suggests, they are long-lived succulent plants that can sometimes live to be up to 100 years old – that is, so long as poachers don't remove them from their native environments. Liveforevers have become popular in the horticultural trade, particularly in Asia, and many species are now endangered due to illegal over-collecting. In addition to harming the Dudleyas themselves, as most don't survive in captivity, poaching activities also damage vital coastal ecosystems, therefore impacting countless other species as well.

In fact, it remains such a threat that McCabe admitted that describing these new rare species presented him with a major catch-22. "If a species has not been named, it is unlikely to get any formal protection," he explained to UC Santa Cruz. "But if it is named, it might become attractive to poachers." In the end, he decided that these species were likely not flashy enough to appeal to the horticultural trade – which could end up saving them from extinction.

[Featured image by Tom Wainwright via Wikimedia Commons | Cropped and scaled | CC-BY-4.0]

Gecko diversity is having a moment lately, with new species being described on a monthly if not daily basis. Even still, it's always exciting when an animal that has managed to evade biologists for years is finally discovered – especially one as large and conspicuous as a gecko. According to a 2023 study published in Zootaxa, a four-day survey of Scawfell Island – a small uninhabited rainforest island in the Great Barrier Reef located around 30 miles off the coast of Queensland, Australia – resulted in the discovery of a secretive new gecko.

The nocturnal creature, which measures about 6 inches long, was found hunting for insects and other small prey in a moist, boulder-strewn landscape punctuated by ferns and fig trees. During the hot days, it likely hides under rocks. Like all leaf-tailed geckos, it has a flattened, spine-fringed tail that resembles a dead leaf. This species also has a pronounced snout, which reminded researcher Conrad Hoskin of "a little dragon."

Because it's only found on one island featuring less than 0.5 square miles of suitable habitat, the new gecko – named Phyllurus fimbriatus – is considered imperiled. Luckily, Scawfell Island is already a protected area, though invasive species and fire pose risks to the small island's wildlife. Still, the discovery calls for celebration. As Hoskin told The Guardian: "Australia's pretty well explored, so it's exciting when we get an instantly obviously new big creature – like a lizard or a frog or a bird – discovered in this day and age."

[Featured image by Conrad Hoskin via Wikimedia Commons | Cropped and scaled | CC-BY-SA-4.0]

Some new species come as a complete surprise. Such was the case in 2018 when scientists first collected an unusual eel-like fish in the deep sea off the coast of Costa Rica. According to a 2023 study published in Zootaxa, the fish was collected using the human-operated submersible, Alvin, which famously explored the wreck of the Titanic in 1986. It was observed swimming around a hydrothermal seep called the Jacó Scar – a warmer biodiverse area with elevated methane levels located at a tectonic plate margin – at a shocking 5,700 to 5,900 feet below the surface.

Things got even stranger when it didn't match up with any known fish. Genetic analysis revealed that it was a new species, which the researchers named the Jacó eelpout, Pyrolycus jaco, in honor of its home. Eelpouts are named for their body shape and dour expressions. The new species is about 6 inches long and is pale lavender-pink. It spends most of its time hiding in rock crevices among reef-like tubeworm colonies and feeding on small invertebrates.

So far, it's the first fish – and first vertebrate species – ever described at the Jacó Scar. "This eelpout discovery is just one example of how special this particular ecosystem is, and by extension, other deep-sea ecosystems that we have not even discovered yet," Charlotte Seid, one of the study's authors, told the Scripps Institute of Technology. "This work highlights the need for further exploration and protection of deep-sea habitats, and the technology that we need to study them properly."

In a 2023 study published in Zootaxa, researchers described two new species of planigale – small shrew-like carnivorous marsupials – living in the Pilbara desert region of northwest Western Australia. Scientists have suspected that there might be undiscovered planigales there for over 20 years, but the creatures are what biologists call "cryptic species," meaning they look nearly indistinguishable from other planigales. Genetic studies of museum and field specimens – as well as careful analysis of habitat and teeth differences – confirmed that they were distinct species.

Though they live in the same region, the two species occupy different ecological niches. The orange-headed Pilbara planigale (Planigale kendricki) has a longer snout and prefers sandy and rocky areas, while the smaller cracking-clay Pilbara planigale (Planigale tealei) (pictured) prefers clay substrates, as its name suggests. These nocturnal creatures feed on insects and prey like lizards that are often as big as they are. This is even more impressive when you consider the fact that they weigh less than a teaspoon of water. In fact, planigales are the world's smallest marsupials.

The voracious mammals not only keep insect populations in check, but they also provide food for many other species. Researchers are desperately attempting to describe and categorize Australia's mammals, which have been declining since European colonization and now face the growing threat of climate change. As lead researcher Linette Umbrello told the Western Australian Museum, "With Australia leading the world in mammal extinctions, it's vital we describe all of Australia's mammals before it's too late."

While surveying an area of the southern Brazilian Amazon Rainforest that is especially threatened by deforestation, a team of entomologists captured a mysterious insect. According to a 2023 study published in the European Journal of Taxonomy, two tiny, 1-inch mantises arrived at their light traps in the early morning. They had pale green bodies, translucent wings, and red antennae. Both were males.

The researchers captured the predatory insects and kept them in enclosures, feeding them moths, monitoring their behavior, and studying what they suspected was an undescribed species. The two mantises were allowed to live out the rest of their lives, then their bodies were analyzed. Sure enough, genetics revealed that they were a new species, which the researchers named the crystalline praying mantis (Microphotina cristalino) after both the region of its discovery and its glasslike wings. Very little is known about how the species spends its days, despite the team spending around two months diligently searching for more specimens.

As a result, researchers believe that the species lives high in the forest canopy. This explains why only males were collected, as females and juveniles cannot fly. Unfortunately, this also means that the enigmatic insect is more at risk of extinction, as it depends on mature forests. The researchers hope that the mantis will become an ambassador for all threatened insects, writing, "Their anthropomorphic appearance, docility, and complex behaviors endow praying mantises with a unique charisma among insects, making them ideal flagship organisms to promote insect conservation."

[Featured image by Leonardo Moutinho Lanna, Lucas Linhares Fiat, João Felipe Herculano, Julio Rivera, and Pedro Peloso via the European Journal of Taxonomy | Cropped and scaled | CC BY 4.0]

Looking like a real-life Halloween decoration, the brightly patterned black and orange Ngoc Linh crocodile newt was certainly an exciting discovery for the researchers who described it – and a surprising one, considering that the place they found it had been surveyed before. According to a 2023 study published in ZooKeys, they discovered the species in the high-elevation tropical evergreen forests of Ngoc Linh Mountain in the Central Highlands of Vietnam, and so far, this seems to be the only place the rare amphibian lives.

These robust, big-headed, 7-inch-long salamanders, which the researchers named Tylototriton ngoclinhensis, hang out on the forest floor under moss and moist logs next to rocky streams. They are most active during the day and likely feed on insects, worms, and other small prey. Like most amphibians, their skin is covered in toxin-secreting warts and glands that deter predators. Living in evergreen forests at an altitude of over 5,900 feet, it's the highest-elevation crocodile newt in Vietnam – at least so far.

It took several trips to the remote forest and rigorous genetic analysis to confirm the find, but lead researcher Trung My Phung knew right away that he had discovered a new species. "I was really surprised when I saw the adults, which were so beautiful that I was shaking and could hardly believe I was holding a live specimen in my hand," he explained to Tuổi Trẻ News. Due to its small range and beautiful coloration – which will surely attract illegal collectors – the newt is already considered an endangered species.

[Featured image by Trung My Phung, Cuong The Pham, Truong Quang Nguyen, Hoa Thi Ninh, Huy Quoc Nguyen, Marta Bernardes, Son Thanh Le, Thomas Ziegler, and Tao Thien Nguyen via ZooKeys | Cropped and scaled | CC BY 4.0]

Sometimes, new species are discovered and documented completely by accident. Such was the case with a particularly attractive Malaysian plant. According to a 2023 study published in the Carnivorous Plant Newsletter, excited botanists were first clued into the species' existence after they saw pictures of it posted by hikers in 2019. After several expeditions and long delays due to the COVID-19 pandemic, researchers located multiple populations of the unusual pitcher plant growing on the rainforest peaks of five mountains in the Titiwangsa Range on the Malaysian peninsula.

Also called monkey pots, tropical plants of the genus Nepenthes use modified leaf "pitchers" filled with thick, sweet fluid to drown small insects and spiders that fall into their lethal traps. Like all carnivorous plants, they extract vital nutrients from their prey that are often not available in the soil they grow in. This particular species – Nepenthes berbulu – is known for its long, bristly-lidded, speckled, and maroon-colored pitchers. Researchers believe that the long bristles on the underside of the lid likely help prey slip and fall into the pitchers below.

Curiously, plants growing in mossy forests at lower elevations have bigger leaves and pitchers and act as vines and epiphytes (plants that grow on other plants), while those higher up are smaller overall and grow as shrubs. What's more, researchers found that its seeds smell like vanilla and also observed that it may have a symbiotic relationship with ants. Due to its small range and striking appearance, this enigmatic species is listed as endangered, with overcollection for the horticultural trade cited as a main threat.

Jellyfish are a diverse but understudied group of organisms. Collecting fragile, soft-bodied, deep-sea species of gelatinous zooplankton, like jellyfish, and keeping them intact so they can be studied is especially challenging. Luckily, technology offered a solution. According to a 2023 study published in Zootaxa, researchers spotted several large, mysterious jellyfish swimming in the deep-sea twilight zone while surveying the waters off of Japan's Ogasawara Islands with a remote-operated submersible vehicle (ROV).

Using the ROV, they were able to photograph the species in their habitat, then again in high definition once one was captured. Finally, they collected two specimens and brought them to the surface for additional study, where genetic analysis revealed that it was not only a new species, but a member of a new jellyfish subfamily. The new species – named the Saint George's cross medusa (Santjordia pagesi) – has translucent flesh, short tentacles, and a bright red stomach that, when viewed from above, looks like a colorful cross on its bell. It likely also has novel venom, which could be important for medical applications.

Only two jellyfish have ever been collected, one in 2002 and another in 2020. Both were swimming within the Sumisu Caldera, an underwater volcano located 2,600 feet below the surface, which is characterized by hydrothermal vents and warmer water temperatures. Despite hundreds of surveys, no other individuals have yet been found, and researchers suspect that the species may be endemic to the caldera. Describing and surveying the rare jellyfish is therefore of utmost importance, as the Sumisu Caldera is currently being explored as a site for underwater mineral mining.

Sometimes, it pays to take a closer look at Earth's forgotten nooks and crannies. According to a 2023 study published in ZooKeys, researchers collected several forest hedgehogs in eastern China and carefully examined their anatomy and genetics. After comparing what they found to the small handful of known forest hedgehog species, they quickly realized that something didn't quite add up. They soon determined that a population of small forest hedgehogs living in the shrubby subtropical forests of Zhejiang and Anhui were actually a new species, which they named the eastern forest hedgehog (Mesechinus orientalis).

It's a small hedgehog, measuring around 7.5 inches from its pointy snout to its stubby tail, and having the heft of a can of soda. It has shorter, black-tipped spines and slightly different skull and teeth features than other species of the genus. So far, it seems that the sexes also look different, with males having gray fur and females being more reddish brown, though further study is needed to confirm that this isn't just individual variation. Hedgehogs are nocturnal, omnivorous mammals that search for food near the ground, and when threatened, they roll up into a spiny ball.

Researchers believe that the eastern forest hedgehog became isolated from its cousins during a cool and dry period around one million years ago, leading to it becoming a distinct species. The discovery brings the total number of Mesechinus hedgehogs to just five species – and there could be more surprises out there. As mammalogist Kai He, one of the study's authors, told Science News, "The mammals of China, especially small mammals, have not been well studied."

[Featured image by Zifan Shi, Hongfeng Yao, Kai He, Weipeng Bai, Jiajun Zhou, Jingyi Fan, Weiting Su, Wenhui Nie, Shuzhen Yang, Kenneth O. Onditi, Xuelong Jiang, and Zhongzheng Chen via ZooKeys | Cropped and scaled | CC BY 4.0]

Researchers investigating biodiverse limestone karst hotspots in a forested national park in northeastern Thailand were treated to a pleasant surprise. According to a 2023 study published in ZooKeys, they noticed several large, shiny millipedes crawling near holes in the rocks. The creatures' bright, iridescent turquoise coloration glittered in the sun and, as the authors noted in the study: "The stark bright color invited collectors to pick them up." Genetic and physical analysis confirmed that the species, later named Sphaerobelum turcosa, was new to science.

Millipedes are land-dwelling arthropods that are closely related to centipedes. Unlike many other species, which are known for their long bodies and large number of legs, pill millipedes have shorter, stockier bodies and far fewer legs. Like their distantly related cousins, the pill bugs, they are capable of rolling up into a tight ball when disturbed. Researchers believe that the species' vivid coloration, which has earned them the nickname "jewels of the forest," is likely aposematic – that is, it deters predators by advertising a warning of toxicity.

So far, the species is known from only one location. In addition to its attractive greenish-blue and yellow coloration, this giant pill millipede – which measures just over half an inch long – has a marking that looks like a bandit mask on its thorax. When the creature rolls up, it matches up with the shield on its other end to create a pattern that resembles a face mask. Like most pill millipedes, it likely feeds on decaying plant matter on the forest floor.

[Featured image by Ruttapon Srisonchai, Natdanai Likhitrakarn, Chirasak Sutcharit, Thierry Backeljau, and Piyatida Pimvichai via ZooKeys | Cropped and scaled | CC BY 4.0]

For years, colorful 2-inch creatures known as "blue moon crayfish" have been sold at pet stores as part of the aquarium trade. According to a 2023 study published in Zootaxa, the crustaceans, which are primarily a slate blue-green with hints of yellow, orange, and black, make attractive ornamental additions to freshwater aquariums and are regularly collected from waterways in Indonesia to be sold worldwide. Curious about the creatures' identity, researchers purchased a few and performed physical comparisons and genetic analysis on them.

After eight years of studying the crustaceans, they realized that what people called "blue moon crayfish" or "blue kong crayfish" were actually five distinct species – one of which was unknown to science. The newly described steel blue crayfish (Cherax woworae) is a burrowing crayfish native to freshwater lakes and streams on the western coast of the Indonesian portion of Southwest Papua, though a few have been found in Hungary's warmer waters. Researchers believe that these isolated occurrences are likely due to irresponsibly released pets.

Some new species have to be seen to be believed. According to a 2023 study published in Marine Biology, researchers surveying the biodiverse seagrass beds and coral reefs off the coast of Okinawa, Japan, discovered not one but two new species of nocturnal pygmy squid. Both were found lurking within the bright green "underwater forests" in the shallow subtropical waters around Japan's Ryukyu Islands. Each named after a creature of Japanese folklore, the tiny cephalopods are the size of your pinkie nail and are as cute as they sound – but don't be fooled.

One of the two, the coral-loving Hannan's pygmy squid (Kodama jujutsu) (pictured), is named both for its round head – reminiscent of the tree-dwelling Japanese forest spirits called the kodama – and its ability to seemingly perform jujutsu when grappling with large prey. It also has a habit of splaying its tentacles as if adopting a martial arts stance. The reddish-colored Ryukyu pygmy squid (Idiosepius kijimuna), meanwhile, is named for the kijimunā – red-haired forest fairies of Okinawa – and spends most of its time clinging to underwater vegetation.

Climate change and human activities could put the unique habitat where the squid live at risk, which is why formally describing them is an important step in their conservation. "Taxonomy is not as flashy as other sciences," Jeffrey Jolly, one of the study's authors, told the Okinawa Institute of Science and Technology. "But through naming and characterizing species, it both highlights the amazing diversity of life in the oceans, and it is a reminder that there is so much that we don't know yet."

[Featured image by Brandon Hannan, Amanda Reid, Noriyosi Sato, Jeffrey Jolly, and Jan Strugnell via Marine Biology| Cropped and scaled | CC BY 4.0]