Tag Archives: coelacanth

Paleontologists Uncover New Early Triassic Coelacanth Species

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Chinese paleontologists have identified a new species of Coelacanth, Whiteia anniae, based on two fossil specimens. This breakthrough expands the geographic presence of the genus Whiteia, marking the oldest record of this genus in Asia, which predates the earliest known pyloid coelacanth in this continent by 9 million years.

Whiteia anniae Right side view, holotype. Image credit: Dai et al., doi: 10.1038/s41598-025-20229-w.

“Coelacanths are a fascinating group of sarcopterygian fishes, with two extant marine species from the genus Latimeria,” stated lead author Dr. Guan Hui Shu, a paleontologist at the Institute of Vertebrate Paleontology and Paleoanthropology, Chinese Academy of Sciences, and colleagues.

“This group first appeared in the Early Devonian, peaked in taxonomic diversity during the Early Triassic, but saw a decline starting in the Middle Cretaceous.”

“Coelacanths play a crucial role in evolutionary biology due to their distinctive physiological and anatomical characteristics, as well as their resilience through four major extinction events over hundreds of millions of years.”

The discovery of Latimeria previously ignited discussions on how this unusual lobe-finned fish relates to the evolution of terrestrial animals.

“Given their evolutionary stability, coelacanths have long been viewed as one of the most morphologically conservative vertebrate groups.”

“However, some research, particularly those focusing on Triassic fossils, indicate that coelacanth body shapes exhibit greater diversity than previously recognized.”

“Recent discoveries of new species around the globe continue to yield significant insights into the evolution of coelacanths.”

The newly identified species, Whiteia anniae, lived during the Smithian stage of the Early Triassic, approximately 249 million years ago.

This fish belongs to the genus Whiteia, an extinct group of coelacanths that were previously known from Madagascar, South Africa, Canada, and Greenland, but not from Asia.

“As the first record in Asia, this new finding from the Early Triassic dramatically broadens the geographic distribution of the genus Whiteia and is a significant addition to our understanding of the evolution of this major Triassic coelacanth lineage,” stated the paleontologists.

Two specimens of Whiteia anniae were discovered in Late Triassic marine deposits at Maoshankou in Anhui Province, China.

Fossil evidence suggests that this coelacanth measured between 41 and 46 centimeters in length, making it notably larger than other named species within its genus.

“Previously reported Whiteia species from the Early Triassic were typically small, ranging from 11.5 to 27 cm in length, and a slender body shape was once believed to be a defining characteristic of the genus,” the researchers explained.

“While there has been a recent trend of recovery, the Whiteia giganteus (estimated to exceed 100 cm in length) from Texas illustrates a period in which the genus achieved larger body sizes during the Late Triassic in North America.”

“The recovery of Whiteia anniae provides an intriguing example of a smaller species, in contrast to larger relatives in Europe, Africa, and North America.”

The team’s study was published on October 17th in the journal Scientific Reports.

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QH.Large et al. 2025. A new species of coelacanth (Actinistia, Sarcopterygii) from the Early Triassic period of Anhui Province, China. Scientific Reports 15, 36320; doi: 10.1038/s41598-025-20229-w

Source: www.sci.news

Scientists Obtain Rare Images of Indonesian Coelacanth

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First identified in 1997 and officially classified as a distinct species in 1999, the Indonesian coelacanth (Latimeria menadoensis) is one of only two extant species of coelacanths. This deep-sea fish closely resembles its ancient Cretaceous ancestors.

A deep diver approximately 1 meter behind the Indonesian coelacanth (Latimeria menadoensis) was found at a depth of 144 m in Northern Mark, Indonesia. Image credit: Alexis Chappuis.

Coelacanths belong to the group of fish known as Sarcopterygians and are characterized by their distinctive coastal dwelling.

Long believed extinct for 65 million years, coelacanths were serendipitously rediscovered in 1938 off the coast of South Africa by museum curators and local fishermen.

These fascinating fish possess unique features, including paired fins and lobed fins that resemble highly modified swim bladders.

Together with lungfish, they are among the closest living relatives to tetrapods, exhibiting several morphological traits not present in more distantly related vertebrates, like ray-finned fish.

The coelacanth first appeared in the early Devonian period, gradually diversifying during the Devonian and Carboniferous periods, with peak diversity observed in the early Triassic.

During the Cretaceous, they were classified into two families: the Latimeridae, which has survived as two species in the genus Latimeria, and the now-extinct Mawsoniidae.

Upon the discovery of the first living specimen, its resemblance to many fossilized forms from the Cretaceous period led to it being labeled a “living fossil,” indicating minimal evolutionary change over millions of years.

The two extant species are the coelacanth of the West Indian Ocean (Latimeria chalumnae) found near the Comoros Islands, and the coelacanth in the waters around Sulawesi, Indonesia.

The latter species is far better documented than its African counterpart, making its deep-reef habitat challenging to access for scientific observation, which has primarily relied on submersibles or remotely operated vehicles (ROVs).

Left profile of the Indonesian coelacanth (Latimeria menadoensis), showcasing a unique pattern of white dots. Image credit: Alexis Chappuis.

The Indonesian coelacanth is a rarely documented medium-deep sea fish (non-tetrapod sarcopterygian), originally endemic to the Sulawesi region, primarily identified through bycatch in eastern Indonesia.

“Very few observations of this species have been made in situ, primarily using submersibles and ROVs.”

“The first direct in situ observations were reported following recent reconnaissance dives that explored the suspected habitat of the Indonesian coelacanth at depths exceeding 150 meters.”

Researchers encountered the Indonesian coelacanth in October 2024 during a deep dive in the Marc Archipelago, situated between Sulawesi and Western New Guinea.

“It is premature to assess the population of this newly identified Malukan coelacanth,” they stated.

“Since the Marc Archipelago connects Sulawesi and Western New Guinea, it suggests that the species is not confined to a single location.”

“Our recent findings, along with studies conducted in the mesophotic coral ecosystems of the Marc Archipelago since 2022, not only confirm the existence of Latimeria but also indicate a broader, more suitable habitat for coelacanths.”

“We hope this discovery will motivate local and national authorities to enhance conservation efforts in this biodiversity-rich region.

The research team’s paper was published online on April 23, 2025, in the journal Scientific Reports.

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A. Chapuis et al. 2025. The first record of a living coelacanth from Northern Mark, Indonesia. Sci Rep 15, 14074; doi:10.1038/s41598-025-90287-7

Source: www.sci.news

Ancient coelacanth fossil from the Devonian era discovered in Australia

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Living Coelacanth Latimeria Coelacanths are iconic “living fossils,” one of the most conservative groups of vertebrates. Now, paleontologists have described a new species of primitive coelacanth from fossils discovered in the Late Devonian Gogo Formation of Western Australia. Ngamgawi WirungariThe 375-million-year-old fossil fish fills an important transitional period in the differentiation and evolution of coelacanths.

Reconstructing your life Ngamgawi WirungariImage courtesy of Katrina Kenny.

coelacanth It is an evolutionarily unique lobe-finned fish that first appeared in the fossil record during the Early Devonian period, approximately 419 million years ago.

More than 175 species of coelacanth fossils are known from the Paleozoic and Mesozoic eras.

During the Mesozoic era, they diversified greatly, with some species developing unusual body shapes.

But at the end of the Cretaceous period, about 66 million years ago, they mysteriously disappeared from the fossil record.

The end-Cretaceous extinction, caused by a giant asteroid impact, wiped out about 75% of all life on Earth, including the non-avian dinosaurs.

It was therefore assumed that the coelacanth was also a victim of the same mass extinction.

However, in 1938, the first specimen of this species was discovered. Latimeria chalumnae It was caught by chance in South Africa.

The second known species, Latimeria menadoensisIt lives off the coast of Sulawesi, Indonesia.

Specimen Ngamgawi WirungariImage courtesy of John A. Long.

“Our study calls into question the idea that extant coelacanths are the oldest 'living fossils,'” said Professor Richard Cloutier, a vertebrate paleontologist at the University of Quebec.

“It first appeared in the geological record more than 410 million years ago, with fragmentary fossils found in places such as China and Australia.”

“But most of the early forms are poorly known. Ngamgawi Wirungari It is the best known of the Devonian coelacanths.

“As we slowly fill in the gaps, we can see how extant coelacanth species are LatimeriaAlthough they are commonly thought of as “living fossils,” they are in fact constantly evolving and may not deserve this enigmatic title.”

Specimen Ngamgawi Wirungari It was discovered in the Late Devonian Go Go Formation Gooniyandi Country in the Kimberley region of northern Western Australia.

Although now covered by a dry rock outcrop, around 380 million years ago the formation was part of an ancient tropical coral reef teeming with more than 50 species of fish.

Coelacanth phylogenetic relationships and divergence dates. Image courtesy of Clement others., doi:10.1038/s41467-024-51238-4.

“Ngamgawi Wirungari “This discovery gives us great insight into the early anatomy of the lineage that ultimately led to humans,” said Professor John Long, from Flinders University.

“Over 35 years, the Gogo site has yielded some perfectly preserved 3D fish fossils and many other important discoveries, including petrified soft tissue and the origin of complex sexual reproduction in vertebrates.”

“The study of this new species has allowed us to analyse the evolutionary history of all known coelacanths.”

“We calculated evolutionary rates over 410 million years of history,” they said.

“This study reveals that the evolution of coelacanths has slowed significantly since the time of the dinosaurs, with some intriguing exceptions.”

of Survey results Published in a journal Nature Communications.

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Alice M. Clement othersLate Devonian coelacanths reconstruct phylogeny, differentiation and evolutionary dynamics of Actinobacteria. Nature Communicationsin press; doi: 10.1038/s41467-024-51238-4

Source: www.sci.news