Galápagos Damselfish Declared Extinct: A 2025 Loss

Did climate change wipe out the Galápagos damselfish (Azurina eupalama)? This once-common, reef-dwelling fish — described by the Galápagos Conservancy as a “shimmering jewel” — hasn’t been seen since the 1982-1983 El Niño Southern Oscillation, which devastated the ecology around the Galápagos. Fueled by climate change, the weather event brought months of warm water to the normally cooler areas where the fish lived and decreased supplies of the plankton they depended on for food. By the time weather conditions returned to normal, the damselfish was nowhere to be found. Divers have spent the past 40 years looking for the fish, to no avail. A 2025 paper published in the Journal of the Ocean Science Foundation concluded that the species should now be considered “likely extinct,” although it encourages ongoing environmental DNA sampling just in case the animal persists. In a press release about this research, the Conservancy wrote that simply mourning this species is not enough. “Every species lost is a page torn from the book of life. But there’s still time to write a different ending. Let this story move us. Let it motivate us. Because we can still make a difference — if we choose to act.” Sadly the Galápagos damselfish is not an isolated story. This past year scientists announced many other species we appear to have lost. Their stories are often haunting, but they can motivate us to learn from our mistakes, take advantage of conservation opportunities, and act to prevent further erosions of the natural world. Here are the stories of the past year, drawn from scientific papers, media reports, and the IUCN Red List. Christmas Island shrew (Crocidura trichura) This tiny but loud species — “its distinctive shrill squeaks could be heard all around as one stood quietly in the rainforest,” according to a 2004 species recovery plan — was last seen in 1985, although its final days really began in the first decade of the 20th century, when humans carried rats (and the rats carried diseases) to Christmas Island. That was just the first blow, though. After that came nonnative yellow crazy ants, cats, and other predators. Then came roads, habitat loss, and — finally — the arrival of yet one more nonnative predator, common wolf snakes, in the 1980s. The last two known shrews were found mid-decade; they died soon after, and the species has long been feared extinct. Last year the IUCN calculated the slim possibility of their continued survival and made it official. The 52-square-mile Christmas Island — a territory of Australia — may not be very big, but it looms large in the extinction crisis. Isolated from other land masses by hundreds of miles of ocean, dozens of unique species had the opportunity to evolve there. That worked just fine until humans arrived and knocked the delicate system out of whack. This shrew is at least the fourth extinction of the island’s unique species. Let’s hope it’s the last. Mimo jiaoyue A paper published in February 2025 described this freshwater mussel for the first time … and declared its possible extinction. The authors based its name on “an ancient Chinese term for the moon, used to describe the shell’s shape as being as round as the bright moon in the night sky.” The species was native to Lake Fuxian in China, but the paper points out that the lake is highly polluted, with low levels of dissolved oxygen, and the shoreline has been destroyed by development. The paper reports that no living specimens have been found and pollution levels suggest it’s “highly unlikely that any surviving populations remain.” (A 2021 paper identified a host of threats to this lake, including “rural domestic pollution, farmland runoff pollution, urban domestic pollution, phosphorous chemical pollution, and tourism pollution.”) And this species may not have been the only one to disappear from the lake: Freshwater mussels rely on specific fish species to host their larvae, and the authors suggest that M. jiaoyue’s unidentified host species may have also gone extinct. Dryadobates erythropus Sometimes we find evidence of extinction not in the wild but in museums or other scientific collections. That’s the case with this 14-millimeter (.55 inches) frog, described by researchers as a new species based on a “badly desiccated and extremely fragile” specimen that had been collected by pioneering herpetologist Doris Cochran in Brazil in 1963 (and stored at the Smithsonian in Washington, DC, ever since). The authors noted that the site where the original specimen was collected “has been transformed into a highly developed residential and commercial area lacking suitable habitat,” so it seems unlikely the frog persists in the wild. Like other so-called “rocket frogs,” this species had a thin, streamlined body, a pointed face, and probably the ability to leap many times its body length. Too bad they couldn’t jump out of the way of humanity. Ngutu kākā (Clianthus puniceus) This shrub with delightful red flower clusters hails from New Zealand’s North Island, where it hasn’t been seen in the wild since 2015, although it still exists in a handful of herbariums. The reasons for its disappearance remain unclear, but it seems likely to have fallen prey to nonnative herbivores such as feral goats, red deer, and snails. Extensive surveys have failed to turn up any free-growing populations, so the IUCN this year assessed the plant as “extinct in the wild.” A related species, C. maximus, persists in the wild — barely — with about 150 known plants (a number New Zealand’s Department of Conservation is actively working to increase). Both species are collectively known as “Kākābeak” because their flowers are shaped like the beak of the kākā parrot (Nestor meridionalis). Slender-billed curlew (Numenius tenuirostris) This once-wide-ranging bird led our annual extinction list in 2024 after a scientific paper declared it lost due to overhunting and habitat loss. This year the IUCN used the paper as the basis for wider scientific consensus and similarly listed the species as extinct. Eugenia acutissima This Cuban plant hasn’t been seen since 1952 and probably fell victim to agricultural development; it was only observed by scientists once. In 2025 the IUCN declared it extinct. Delissea sinuata Native to the Waianae Mountains of Oʻahu, this plant hasn’t been seen since 1937. Nonnative species have heavily degraded its former habitat — another example of why Hawai‘i is often referred to as the “extinction capital of the world.” It would be easy to spot if it still existed, because it grew up to four feet high and bore striking purple berries. Diospyros angulata Proof that science takes its time: This plant from the island of Mauritius (home of the infamously extinct dodo) was last seen in 1851. The IUCN finally published an assessment identifying the species as extinct in 2025. The likely causes of its extinction include logging, grazing, soil erosion, and competition from nonnative plants and animals. Syzygium ampliflorum This tree grew on an active volcano — Mount Galunggung in Java, Indonesia — which last erupted over a nine-month period beginning Oct. 8, 1982. The eruption killed 2,000 people, wiped out 88 villages, and presumably caused this plant’s extinction — that is, if it hadn’t already been killed off during earlier eruptions in 1894 and 1918. An expedition in January 2025 failed to turn up signs of this plant’s existence, and a paper published in September suggested it should now be considered possibly extinct. If so, that would make it one of the few extinctions on this list not directly linked to human activity. Brunoniella neocaledonica This small, flowering herb from New Caledonia was only documented twice, in 1967 and 1968. Its only habitat has suffered from frequent fires and grazing from nonnative Rusa deer. The IUCN assessed it as extinct in 2022 but only published that in 2025. Another rarely documented New Caledonian herb — Pytinicarpa tonitrui — faced the same threats and has also been declared extinct. Kākāpō parasites New Zealand’s critically endangered kākāpō parrots (one of our species to watch in 2026) nearly went extinct a few decades ago. Conservationists saved the species by moving the last of these flightless birds to safe, predator-free islands. They’ve been doing fairly well ever since and may experience a baby boom in the year ahead, but they’ve lost something else along the way: their parasites. A study published this past July found more than 80% of the parasite species previously associated with kākāpō prior to the 1990s have disappeared. Of the 16 parasites the researchers identified, only three remain on the birds. The paper suggests that four of these parasites were associated exclusively with kākāpō and, with no other species to host them, have gone extinct. This might seem like a “no big whoop” deal, but parasites rarely deserve their bad reputation. They often play important ecological roles — research suggests they can help keep our immune systems healthy and may even protect us from any new, potentially more destructive parasites that arrive. Their disappearance, meanwhile, is a sign that natural systems are deeply disturbed — and if a habitat can’t support a parasite, what does that mean for the fate of the host species? A press release about this research gives us further food for thought. It reminds us that parasites live on a small proportion of the population of their host species, so when the bigger species become endangered, the parasites are likely to go extinct faster than the hosts (a process called secondary extinction or coextinction). This means parasite declines could be considered an early warning system and tip us off to problems in the hosts. At the same time, the paper warns that we may have underestimated the rate of parasite extinction worldwide and failed to account for them in our documentation of disappearing species. Case in point: What if every extinction announced this year also involved the extinction of one or two parasite species? So let’s spare a moment to think about these lost species — and maybe give those that remain a little extra attention and appreciation. Madeiran large white (Pieris wollastoni) This striking, 2-inch butterfly once flew in Madeira, an autonomous region of Portugal, but hasn’t been seen since 1986. The IUCN SSC Butterfly Specialist Group assessed it as extinct in 2023, but that wasn’t published to the IUCN Red List until last year. The cause of its extinction remains unclear, but possible factors include pesticides, a virus, or the decline of the plants the butterflies’ larvae depended on. Conus lugubris This poor little cone snail was once abundant on the Cape Verde Islands, which have since become a tourist mecca. Rapid coastal development since the late 1980s has destroyed the snails’ habitat and the species is now presumed extinct. Leptaxis vetusta This Portuguese land snail was scientifically described in 1857 based on a fossil shell and has never been observed alive. The IUCN this past year assessed it as extinct. Mastigodiaptomus galapagoensis This small copepod (a type of crustacean) lived until recently in El Junco, a high-elevation freshwater crater lake on San Cristóbal island in the Galápagos that has no naturally occurring fish. An illegal attempt to establish a tilapia fishery there in 2005 or 2006 devastated the lake’s ecology. By the time efforts to eradicate the nonnative fish began in 2008, the lake held an estimated 40,000 tilapia. Native invertebrates didn’t stand a chance. A paper published in 2021 suggested this had caused an extinction; the IUCN this year gave broader consensus to that sad reality. Snowy owls (Bubo scandiacus) in Sweden Sometimes species disappear on the regional level, which is known as extirpation rather than extinction. This year the conservation organization BirdLife declared snowy owls regionally extinct in Sweden, a decade after the last sign of the birds breeding in that country. BirdLife says this should serve as a warning for all northern countries in which snowy owls still roam, where climate change is rapidly altering ecosystems and making them less hospitable to these iconic birds (and so many other species in the process). Thaumastus teixeirensis Another land snail, this time from Brazil. Scientists have previously identified dozens of other species in this genus, but this one slipped by until a paper published this past year. Evidence of the species emerged from sambaquis — shell mounds left as monuments by prehistoric people. Researchers found the shells for this new species in these mounds and wrote that “efforts to find similar living specimens, or even empty shells, in that region were fruitless, strongly suggesting that the species is currently extinct.” Acropora corals Not an extinction, and not an extirpation, but about as close as you can get: A paper published this past October warned that an “acute heating event” along the Florida Keys in 2023 killed between 97.8% and 100% of elkhorn (Acropora palmata) and staghorn (A. cervicornis) coral colonies. So many corals died that further reproduction remains unlikely, leaving the species in this area “functionally extinct.” This is climate change in a nutshell, folks. Several Italian plant species A massive study of the vascular plants of Italy (i.e., most plants other than mosses and the like) reassessed 628 species, resulting in conservation status updates for 44% of them. The 100-plus authors fanned out across the country and found that the fate of 57 species has improved. But they also found that 176 species fared worse than their previous assessments, and the researchers confirmed several regional and national extinctions, mostly in aquatic habitats. Among the losses: Atriplex mollis in Sardegna Coleanthus subtilis in Trentino-Alto Adige Taraxacum pauckertianum in Toscana Aldrovanda vesiculosa all over Italy Mentha cervina in Abruzzo Nuphar lutea and Nymphaea alba in Sicilia Utricularia minor and vulgaris in Toscana Potamogeton gramineus and Sonchus palustris in Veneto Crucianella maritima in Calabria Juniperus sabina in the Marche Other countries would do well to follow the lead of these Italian botanists. As they write in the paper, “This research also underscores the importance of botanical collections and historical records to reconstruct the history, dynamics, and current distribution of plant species, and addresses challenges such as limited access to the collections. This study is not only a milestone in Italian floristics but also provides a replicable methodology for updating national floras globally.” Six bandicoots These long-unseen (and in some cases newly identified) Australian marsupials got their first — and last —entries on the IUCN Red List this past year when all were listed as extinct species: Northern pig-footed bandicoot or Yirratji (Chaeropus yirratji) and southern pig-footed bandicoot (C. ecaudatus) — Previously considered one species, they were reassessed as two species in 2019 using a combination of fossil records, Aboriginal oral accounts, bones, and taxidermied specimens. Unseen since the 1950s and 1930s, respectively, the two bandicoots probably disappeared due to introduced predators (like cats and foxes), changes in fire regimes instituted by European settlers, and habitat degradation by livestock. The rest of the bandicoots on this list faced similar stories. Nullarbor barred or butterfly bandicoot (Perameles papillon) — Last seen alive in 1928 and identified as their own species in 2018 based on museum specimens. The only known photos of this species were rediscovered in 2025. South-eastern striped or southern barred bandicoot (Perameles notina) — Last seen in the mid-19th century. Liverpool Plains striped bandicoot (Perameles fasciata) and southwestern barred bandicoot or Marl (P. myosuros) — Previously considered subspecies, these bandicoots were elevated to full species status in research published in 2018. They were last seen in 1846 and 1907, respectively, and cats once again get the blame for most of their declines. Three Caribbean lizards A recent study took a deep dive into the DNA of forest lizards from the Cayman Islands, Jamaica, and Hispaniola and shook things up quite a bit, ultimately defining 35 new species — including one that lives near Goldeneye, Jamaica, where author Ian Fleming wrote his James Bond novels (they of course named the species Celestus jamesbondi). In the process they declared the Altagracia giant forest lizard (Caribicus anelpistus) and yellow giant forest lizard (Celestus occiduus) “critically endangered (possibly extinct)” (assessments already made by the IUCN Red List under different common names) and added a newly identified species, the black giant forest lizard (Celestus macrolepis), to the list of lost species. Armeria maritima An odd case to wrap up this list: Botanists considered this species “extinct in the wild,” with the last living samples growing at Utrecht University Botanic Gardens in the Netherlands. But recent DNA tests of the living plant and 19th-century specimens showed that the gardens actually held a hybrid of two different Armeria species. That allowed them to declare that Armeria arcuate is truly extinct — but at the same time it illustrated the value of botanical gardens and herbarium collections, which can still provide critical scientific evidence even if the samples are decades or centuries old. Many herbarium collections themselves face extinction in an age of scientific budget cuts, so that’s an important message we’d do well to take to heart. Previously in The Revelator: