Tag Archives: fangs

Discovering the Origins of Spider Fangs: Tracing Ancient Marine Life Back to 518 Million Years Ago

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Urocodia equalis

is an early Cambrian marine predator from China’s Chengjiang biota, notable for preserving the earliest evidence of chelicerae. This unique structure is a precursor to the fangs of spiders and pincers of scorpions.



Artist’s impression of Urocodia equalis, a marine predator that roamed Cambrian seas around 518 million years ago. Image credit: Xiaodong Wang.

Spiders, scorpions, and ticks belong to a significant group of invertebrates known as chelicerates, which includes over 100,000 described species.

Characterized by articulated limbs and an external skeleton, these creatures are particularly known for their specialized limbs, called chelicerae, used for capturing prey.

The earliest fossil records of chelicerae emerged not from terrestrial habitats but from marine organisms inhabiting Cambrian seas over 500 million years ago.

In a groundbreaking study, paleontologists examined Urocodia equalis from the renowned Chengjiang Fossil Site in Yunnan Province, China.

This diminutive creature measures just 2 to 3 centimeters and features large, stalked eyes, a segmented skeleton, and articulated limbs extending from its elongated body.

“The Urocodia equalis was part of an ancient ecosystem with over 200 species thriving in the ocean more than 500 million years ago,” stated Professor Mark Williams from the University of Leicester.

“These excellently preserved fossils offer invaluable insights into the early evolution of life on Earth.”

Utilizing X-ray tomography, Professor Williams and his team conducted an in-depth analysis of Urocodia equalis, uncovering much of its soft tissue still intact.

The scans revealed small, scissor-like limbs located behind the eyes, representing an early evolutionary version of the chelicerae that later developed into the fangs of spiders and pincers of scorpions.

“During our X-ray tomography analysis, we discovered soft anatomy that had remained buried for millions of years, including these fascinating scissor-like limbs,” remarked Professor Yu Liu, a paleontologist at Yunnan University and the University of Leicester.

“This fossil is particularly intriguing as it is a distant ancestor of chelicerates like scorpions and spiders.”

Urocodia equalis‘s legs also exhibit features similar to gills, a respiratory adaptation still observed in modern horseshoe crabs.

This discovery extends the fossil record of this unique trait, providing a rare glimpse into the origins of one of evolution’s most successful hunting adaptations that emerged in ancient oceans.

“Urocodia equalis has a seven-segmented head with a sclerotized lower mouth, pincer-like appendages, and bilobed body appendages equipped with overlapping exit valves,” noted the paleontologists.

“These scissor-like appendages illustrate a transitional structure between a multi-segmented appendage and a true chelicera; mega keiran represents the origin of book gills.”

Further details of these findings are published in the latest issue of Nature.

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Y. Liu et al., Urokodia: Shedding light on the origin of chelicerae and their book gills. Nature, published online July 1, 2026. doi: 10.1038/s41586-026-10713-2

Source: www.sci.news

Unique Needle-Like Fangs Found in Teeth of Extinct Shark

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Paleontologists have described a new species of extinct ramid shark Paleohypotodus Based on 17 fossilized teeth found in Alabama, USA.

Fossilized teeth are Paleohypotodus bizocoi.Image credit: Eversole other., doi: 10.3897/fr.27.e112800.

“Paleohypotodus “Sharks are an extinct genus of sheep-like sharks that range in time from the late Cretaceous (Maastrichtian) to the late Eocene (Priabonian), with isolated teeth scattered over large areas around the world. It has been reported from different sources,” said Dr. June Ebersole. McWane Science Center Collections Director and his colleagues.

“There are three recognized species in this genus, including the Cretaceous. Palaeohypotodus bronniand Paleogene Paleohypotodus borgensis and Palaeohypotodus rutoti”

“These species have an upright to strongly hooked distal crown, a smooth cutting edge, one or more pairs of lateral cusps, and a unique combination of folds along the labial crown foot. It is characterized by sturdy teeth.

“Paleohypotodus Although known primarily by solitary teeth, at least one partially associated skeleton has been reported. ”

The newly identified species is Paleohypotodus bizocoilived about 65 million years ago (Paleocene epoch).

A collection of 17 teeth belonging to this species was recently discovered in the historical collections of the Alabama Geological Survey in Tuscaloosa.

The specimen is Porter's Creek Formation Originally from Wilcox County, Alabama.

“A few years ago, while looking through our historic fossil collection at the Alabama Geological Survey, we came across a small box containing a shark tooth collected in Wilcox County over 100 years ago,” Eversole said. the doctor said.

“We've been documenting fossilized remains of hundreds of fish species over the past decade, but it was puzzling that these teeth belonged to sharks we didn't recognize.”

Paleohypotodus bizocoi It was a major predator when the ocean was recovering from the mass extinction at the end of the Cretaceous.

“In Alabama, during the Paleocene, much of the southern half of the state was covered by shallow tropical to subtropical oceans,” says T. Lynn, a paleontologist and curator of fossil collections at the Alabama Geological Survey. Dr. Harrell Jr. says. .

“This era is less well studied, which makes the discovery of this new species of shark all the more important.”

“Shark discoveries like this one give us tremendous insight into how marine life recovers after large-scale extinction events. We also know that global events such as climate change are changing the way our oceans are today. We may also be able to predict how this will affect living organisms.”

As part of their study, the authors compared fossil teeth. Paleohypotodus bizocoi to sharks from a variety of modern sharks, including great whites and shortfin mako sharks.

“By studying the jaws and teeth of extant sharks, we were able to reconstruct the dentition of this ancient species and found that it has a tooth arrangement unlike any other living shark.” said Curator of History Dr. David Sisimuri. Carolina State Museum.

a paper A description of the discovery was published in a magazine fossil record.

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JA Eversole other. 2024.new species Paleohypotodus Glickman, 1964 (chondrichthyes, oligidae), collected from the Lower Paleocene (Danian) Porters Creek Formation, Wilcox County, Alabama, USA. fossil record 27 (1): 111-134; doi: 10.3897/fr.27.e112800

Source: www.sci.news

A new frog species with tiny fangs found in Indonesia

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Biologists have discovered a new species of land-nesting tree frog Limnonectes Lives in Sulawesi, Indonesia. Adult body size is the smallest of all species. Limnonectes Island Frog – Maximum nostril length is approximately 3 cm (1.2 inches).

Limnonectes phylofolia.Image credit: Frederick other., doi: 10.1371/journal.pone.0292598.

Limnonectes is a large genus of the fork-tongued frog family Dicroglossaceae.

This genus includes more than 75 scientifically recognized species. They are collectively known as fanged frogs because they tend to have unusually large teeth that are small or absent in other frogs.

They use their fangs to compete with each other for territory and mates, and sometimes hunt hard-shelled prey such as giant centipedes and crabs.

Limnonectes The species is distributed from India through China, Indochina, Thailand and the Malaysian Peninsula, to the Sunda Shelf landmass (Borneo, Sumatra, Java), the Marx Islands, the Lesser Sunda Islands, parts of western New Guinea, and the Philippines. .

Larger species prefer fast-flowing rivers, while smaller species live in fallen leaves or on riverbanks.

‘The reproductive biology of the yellow-throated frog is surprisingly complex,’ say researchers at the Field Museum of Natural History. Jeffrey Frederick and his colleagues.

“For example, the two Malay races Limnonectes hasianus and Limnonectes limborgii, together with larval ontogeny, demonstrate protection of terrestrial eggs by males. The larvae hatch as free-living tadpoles, but remain in a nest guarded by the male and survive solely on nutrition from the yolk sac. ”

“Four types of Limnonectes From Borneo, Limnonectes coulis, Limnonectes bruti, Limnonectes Ibanorumand Limnonectes ingeri They are “voiceless” and lack a vocal sac for advertising calls. ”

The name of the newly described species is Limnonectes phylofolialives on the island of Sulawesi, a rugged mountainous island that forms part of Indonesia.

“Sulawesi is a huge island with vast mountain ranges, volcanoes, lowland rainforests and mountain cloud forests,” Dr Frederick said.

“The existence of all these different habitats means that the scale of the biodiversity of many plants and animals we discover there is unrealistic, comparable to places like the Amazon.”

“Limnonectes phylofolia “It is small compared to other fanged frogs on the island where it has been found, about a quarter of the size,” he added.

“Many frogs in this genus are huge, weighing up to 2 pounds. This new species weighs, to put it simply, about the same as a dime.”

To the surprise of the research team, Limnonectes phylofolia All individuals caring for eggs were male.

“Male frogs guard one or more eggs garnished with leaves or moss-covered rocks 1 to 2 meters above slow-moving streams, rivulets, or leachate,” the researchers said. said.

“Such behavior is not completely unknown in all frogs, but it is rather rare.”

They hypothesize that the frog’s abnormal reproductive behavior may also be related to smaller-than-normal fangs.

“Some members of the frog family have larger tusks, which help them avoid competition for places to lay their eggs in the water along rivers,” the researchers said.

“Because these frogs have evolved a way to lay their eggs away from the water, they may have lost the need for such large, impressive fangs.”

“It is interesting that with each subsequent expedition to Sulawesi, new and diverse modes of reproduction are discovered,” concluded Dr. Frederick.

“Our findings also highlight the importance of protecting these very special tropical habitats.”

“Most of the animals that live in places like Sulawesi are very unique, and habitat destruction has always been a pressing conservation issue in order to preserve the great diversity of species found there. Masu.”

“Learning about animals like these frogs, which are found nowhere else on Earth, can help advocate for protecting these precious ecosystems.”

discovery of Limnonectes phylofolia is reported in paper in diary PLoS ONE.

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JH Frederick other. 2023. A new species of land-nesting tusked frog (Dicroglossidae) from Sulawesi, Indonesia. PLoS ONE 18 (12): e0292598; doi: 10.1371/journal.pone.0292598

Source: www.sci.news