99-Million-Year-Old Amber Contains the Earliest Mosquito Larvae

This newly discovered fossil, preserved in amber from Myanmar’s Kachin region, marks the first instance of a mosquito larva found in amber and represents the earliest immature mosquito of the Mesozoic era, designated as a new genus and species: Cletosabetes primaevus. This discovery strongly suggests that the mosquito family Culicidae has its origins in the Jurassic period and indicates that its larval structure has remained largely unchanged for at least the past 99 million years.

Larva of Cletosabetes primaevus. Image credit: Amaral et al., doi: 10.1016/j.gr.2025.09.011.

Mosquitoes comprise a vast group of insects, with over 3,727 known species alive today.

Although small, they are quite noticeable and widely distributed, playing significant roles in ecosystems, human history, and both human and veterinary health.

To date, 31 species of mosquito fossils have been documented. These ancient mosquitoes closely resemble modern species and are classified within the same genus as their modern counterparts.

“The earliest known mosquito fossils are adults, also found in amber dating back about 99 million years,” stated Dr. Andre Amaral from Ludwig-Maximilians-University of Munich and his team.

“Given their morphological distinctions from living species, they are considered part of a separate group, Burmaculicinae, representing an extinct lineage within Culicidae.”

The authors note that Cletosabetes primaevus belongs to the Sabetini group, which includes existing species.

Similar to the larvae of current Sabetini species, this new species’ larvae likely thrived in small water bodies.

“According to currently uncovered fossils, the evolutionary roots of mosquitoes are believed to be in the Jurassic period, roughly 201 to 145 million years ago,” the researchers remarked.

“Molecular phylogeny analyses yield varying conclusions, from the Triassic to Jurassic periods.”

“Our research strongly indicates that mosquitoes had already diversified during the Jurassic period, with their larval structure remarkably consistent for nearly 100 million years.”

“This finding challenges previous notions regarding the early evolution of this insect group and offers fresh insights into its evolutionary ecology.”

A segment of amber containing Cletosabetes primaevus larvae was sourced from the Kachin Amber Mine in Myanmar’s Hukaung Valley.

This amber dates back to the Late Cretaceous, about 98.79 million years ago.

“This fossil stands out as the larva closely resembles modern species. Unlike other mosquito fossils from this period, it displays distinct morphological features no longer found in today’s species,” Dr. Amaral explained.

A paper detailing Cletosabetes primaevus was published in this month’s edition of Gondwana Research.

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Andre P. Amaral et al. 2025. The first fossilized mosquito larva discovered in 99-million-year-old amber illuminates the evolutionary history of mosquitoes (Diptera: Mosquitoidae). Gondwana Research 150: 154-162; doi: 10.1016/j.gr.2025.09.011

Source: www.sci.news

Two Parasitic Bacteria Discovered in 99-Million-Year-Old Amber

The fossilized bacteria from Cachin Amber in Central Cretaceous belong to the same family as the zombie ant bacteria, ophiocordyceps unilateralis, which has become well-known as the inspiration for various popular apocalyptic video games and TV series, such as Our Last.



Ecological reconstruction of Cretaceous insects and insect pathogenic fungi. The ants have abandoned the infected PUP, and the infected fly is located on the trunk of a distant tree. Image credit: Zhuang et al., doi: 10.1098/rspb.2025.0407.

Two newly identified species, Paleoophiocordyceps gerontoformicae and Paleoophiocordyceps Ironomyiae, represent some of the oldest fossil records of animals and pathogenic fungi.

These specimens were discovered in 99-million-year-old fragments of Kachin amber, sourced from a mine near the village of Neuebham in northern Myanmar.

“Insects and fungi are among the most diverse groups of living organisms, cohabiting Earth’s ecosystems for over 400 million years,” explains Professor Edmund Jalsenbowski, a paleontologist at the Geology, Paleontology and Natural History Museum in London, along with his colleagues from the Nanjing Institute of Studies.

“Consequently, they have developed intricate and close ecological relationships, including reciprocity, predation, and parasitism.”

“Entomopathogenic fungi, in particular, have garnered attention for their role in regulating insect populations, though much remains unclear about them.”

“The infection process begins when spores come into contact with the proper host, initiating germination through enzymatic hydrolysis, allowing entry into the insect’s body cavity (hemocoel).”

“Once the fungus infiltrates the insect’s body, it (as yeast-like cells at this phase) proliferates via budding, consuming the host’s body from within.”

“Eventually, the host typically succumbs to fungal toxins, leading to the formation of chains of yeast-like cells that transition to the filamentous stage shortly after the host’s death.”

“These filaments gradually organize into compact spore-producing structures (sporocaps) that emerge from the softer parts of the insect, dispersing spores into the environment to infect additional hosts.”



Holotype of Paleoophiocordyceps Ironomyiae. This comparison of mid-Cretaceous specimens shows similarities with existing Bacillus ophiocordis: (a, b) Lateral and dorsal views of the bipteran host, where potential fungal structures are visible. (c) Closure of the fungal stroma of Paleoophiocordyceps Ironomyiae; (D, E) Apex of the fungal stroma. The red arrows indicate the surroundings. (f, g, h) Presence of ophiocordyceps stromas for Ant and Dipteran hosts. Scale bars – 0.5 mm (a, b), 0.1 mm (c) and 50 μm (d, e). Image credit: Zhuang et al., doi: 10.1098/rspb.2025.0407.

According to the authors, Paleoophiocordyceps gerontoformicae was found in a young ant, while Paleoophiocordyceps Ironomyiae was discovered on a fly.

“It’s captivating to observe that some of the unusual phenomena we witness today were also present during the age of dinosaurs,” remarked Professor Jarzembowski.

“Known as a zombie fungus, it can influence the behavior of its host, a feature that has been depicted in popular apocalyptic video games and series like Our Last.”

“Given that the infection is lethal, ophiocordyceps and its fossil counterparts likely played a significant role in regulating insect populations during the Middle Cretaceous, similar to how their modern relatives do today.”

“While parasitism is common in today’s ecosystems, evidence of these interactions is seldom found in the fossil record.”

“This is primarily due to the poor preservation of their soft tissues in fossils and the fact that they reside within their hosts, making identification among insect remains challenging.”

“While ancient parasite specimens have been uncovered, our understanding of their evolution remains limited.”

“This new discovery provides rare insight into these parasites from a long-ago era.”

The team’s research paper was published in the June 2025 issue of Proceedings of the Royal Society B: Biology.

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Yuhui Zhuang et al. Cretaceous insect pathogenic fungi illuminate the early evolution of insect-fungal associations. Proc. R. Soc. B 292 (2048): 20250407; doi: 10.1098/rspb.2025.0407

Source: www.sci.news

A 99-million-year-old skink found preserved in Burmese amber is the oldest ever discovered

Palaeontologists have discovered the fossil of a previously unknown species of lizard in mid-Cretaceous amber unearthed in northern Myanmar.

Reconstructing your life Electrosincus Zeddyparts of the lizard not represented in available sources have been blurred. Image courtesy of Stephanie Abramowicz.

The newly discovered species was a small lizard, estimated to be about 3 centimetres (1.2 inches) long from snout to anus.

Named Electrosincus ZeddyIt lived during the mid-Cretaceous period, about 99 million years ago.

Unlike other squamate animals (lizards and snakes) that lived during the Mesozoic era, they have a layered and complex structure. Cortical bone They are arranged alternately around the body, supporting its classification as a lizard. Gerbils.

“The family Pectiniidae is a highly diverse lineage of squamate animals that is now nearly universally distributed in temperate and tropical regions around the world,” said Dr. Juan Daza of Sam Houston State University and colleagues.

“This comprises more than 1,745 described extant species, about 15 percent of all extant lizards.”

“Typically, lizards have cylindrical bodies and relatively short limbs, and evolution towards shortening or loss of limbs has occurred in more than 50 lizard lineages.”

“Among the living syncoids (Xanthus, Gerphosauridae, Cordylidae, and Syncoidae), syncoid species have the greatest range in body length, ranging from tiny species just a few centimetres in length to extinct species. Tiliqua FrangensIt may have reached a height of more than 50 centimetres.”

“Skinks also vary greatly in the number of presacral vertebrae, ranging from 26 to 108, which, together with round scales and compound bone plates, may have facilitated the repeated evolution of depressed and limbless morphologies.”

“Most lizards have smooth, circular scales beneath which extend compound osteoderms, which are bony plates within the dermis made up of multiple articulating dermal fragments per scale.”

Electrosincus ZeddyVentral (a) and dorsal (b) views of the fossil. Detail of the right foot (c, e) and bone plate (d). X-ray of the entire specimen, showing skeletal remains and some articulated and scattered bone plates (f). Image courtesy of Daza. others., doi: 10.1038/s41598-024-66451-w.

One Burmese Amber (Burmit) Preservation Electrosincus Zeddy It was discovered in a Mid-Cretaceous outcrop about 100 km west of Myitkyina Township, Myitkyina District, Kachin State in northern Myanmar.

The specimen contains two separate parts of a lizard, including scales and mainly appendicular bones, but is clearly part of a single individual.

“To date, more than 100 squamate specimens have been discovered in Burmite,” the paleontologists said.

“Within this large sample, the new fossil is the only one that preserves this cortical bone morphology, which makes it diagnosable as a Snecidae and distinguishes it from all known fossil squamates from the Cretaceous.”

“Although the specimen is incomplete, it preserves both postcranial skeletal elements and integumentary structures, which, although less than ideal, provides a basis for comparison with putative synthid specimens that may be discovered in the future.”

“This specimen has a combination of compound bony plates and overlapping circular scales that are only seen in lizards.”

“We suggest that this type of osteoderm evolved as a response to increased scale overlap and reduced stiffness of the skin armour,” the researchers concluded.

Their paper Published in the journal Scientific Reports.

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JD Daza others2024. A compound osteoderm preserved in amber identifies it as the oldest known lizard. Scientific Reports 14, 15662; doi: 10.1038/s41598-024-66451-w

Source: www.sci.news

Discovery of ancient marine tapeworm preserved in 99-million-year-old amber

Paleontologists from the Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences, and others have discovered a partial fossil of an ancient tapeworm preserved in Kachin amber from Myanmar from the mid-Cretaceous period.

A 99-million-year-old amber fragment containing a tapeworm fossil (long tentacles) and other inclusions: (AB) Overall view of the amber fragment. (C) Trichophytes of Gleichenidae. (D) Scale insect larva. (E) Sand grains. Scale bar – 2 mm inches (A, B), 0.1 mm inches (CE).Image credit: Luo other., doi:10.1130/G52071.1.

Parasites, especially parasitoids, are ubiquitous in extant ecosystems but poorly preserved in the geological record.

One such group is Sestoda (tapeworms), a special group of internal parasites flatworm.

These organisms have complex life cycles with at least two hosts and infect all major vertebrate groups.

However, due to its soft tissue and hidden habitat, the fossil record is very sparse, with the only widely accepted example of a pre-Quaternary period being a shark egg found in a Permian coprolite. be.

The lack of body fossils greatly hinders our understanding of early evolution.

Dr. Bo Wang, a researcher at the Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences, said: “The fossil record of tapeworms is extremely poor due to its soft tissue and endoparasite habitat, which is a major hindrance in understanding its early evolution. ''. Science.

The new fossil exhibits unique external (armature pattern) and internal (partially invaginated tentacles and rootless hooks) features that are most consistent with extant tentacles. Trypanolhynch tapeworm Parasitic substances of marine life elasmobranch (mainly sharks and rays).

“This discovery is the most convincing platyzoan fossil ever discovered,” said Dr. Cihang Luo. candidate at Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences.

“Our study provides an exceptional example of a marine endoparasite trapped in amber and also sheds new light on amber taphonomy.”

“Specifically, we showed that amber can preserve the internal structure of helminths.”

“Using high-resolution micro-CT, we discovered that inside the modern fossil, a folded vertical structure extending spirally around the longitudinal axis extends to the very front. It matches the tentacle you entered.”

“On the other hand, rootless hooks are the same as trypanorhynch hooks.”

“Previous studies have shown that internal structures can be preserved intact, similar to modern forms, but all such studies have focused on arthropods.”

A hypothetical ecological recreation of the Trypanorhynch tapeworm fossil. Image credit: Dinghua Yang / Luo other., doi:10.1130/G52071.1.

“Our results show that amber can preserve the internal structure of helminths such as tapeworms over geological time scales,” Dr. Wang said.

“In addition to remarkable examples of marine endoparasites trapped in amber, several Gleichenia trichomes and scale insect larvae were also preserved in the same amber specimen along with partial insect remains. I did.”

“This clearly indicates that it was in a terrestrial or terrestrial environment at the time it was trapped in the resin.”

“Additionally, many sand grains are evenly distributed throughout the amber, suggesting that the fossil was buried in a sandy environment.”

“Furthermore, evidence so far indicates that Kachin amber was deposited in a near-shore environment.”

“One possible scenario for the tapeworm being deposited in the amber is that its elasmobranch host became stranded by tides or storms.”

“In such a scenario, the host would have been bitten by a high level of terrestrial predator or scavenger.”

“When the host was consumed by a predator, the tentacles were pulled apart, detached from the intestine, and attached to nearby resin.”

“Our study further supports the hypothesis that Kachin amber was probably deposited in a paleoenvironment in the Pala region, and also highlights the importance of amber studies in paleoparasitology.”

team's paper It was published in the magazine geology.

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Jikyoura other. Exceptional preservation of marine tapeworm tentacles preserved in Cretaceous amber. geology, published online March 22, 2024. doi: 10.1130/G52071.1

Source: www.sci.news