ago more than 300 million yearsand insect of extraordinary proportions reigned in the skies of the primitive world. The meganeura had an extension of wings that exceeded 70 centimetersand it was the flying insect largest that inhabited the Earth.
Meganeuraan extinct species and before the dinosaurs In almost 100 million years, it flew over the swampy forests of the Carboniferous period. Their large compound eyesadapted for precise vision, allowed him to detect small amphibians and insects among the vegetation.
Con long wings and provided with a complex network of veinswas designed for fast and precise flights, which made it an efficient predator.
The first traces of meganeura were found in 1880 in Commentry, France, where paleontologist Charles Brongniart identified this winged titan. Later, other fossils turned up in England and the United States, revealing details about their anatomy and habitat.
As explained by the biologist Alejandra Paganiresponsible for the Scientific Area of the Egidio Feruglio Museum (MEF) and researcher of CONICETa Infobae “What draws the most attention about meganeura is its size, as well as many other groups of insects or invertebrates that reached giant sizes for the Carboniferous.”
Why did this species attract the attention of scientists? Because it is one of the largest insects that have ever existed, which stood out for its impressive dimensions and the structure of its wings, adapted to dominate the skies millions of years ago. “Meganeura had a wingspan of about 70 centimeters with open wings. And there is another species, Meganeuropsis permianawhich reaches 71. No current insect reaches that size,” explained Pagani.
And he added: “The wings were longnarrow, with complex ribs that gave them rigidity and flexibility. This allowed it to maneuver very precisely in flight, something crucial to hunt its prey in mid-air,” Pagani explained. In fact, the name meganeura comes from Greek, which means “large nerves or veins”, in reference to this network of veins in its wings.
Furthermore, the anatomy of chest It had peculiar characteristics. “Everything that was the part of the thorax, where the wings go, had an asymmetrical shape and it is estimated that this helped it hunt while flying,” he added.
Los eyes of Meganeura are other of its most surprising characteristics, which Pagani defined as “quite complex, which allowed them a very particular vision.” What were they like? Large and prominent, they were adapted to improve their ability to see in flight, a key detail for an aerial predator.
“A characteristic possibly associated with its behavior was that it had very large compound eyes, with various lenses, dorsally hypertrophied ―bigger than usual―, that is, they were raised dorsally. This allowed it to fly faster than modern dragonflies. and its vision should have been very good, which would give this animal long-distance vision, which could see above itself as it flew,” Pagani explained.
In addition, the meganeura eyes are another of their most surprising characteristics, which Pagani defined as “quite complex, which allowed them a very particular vision.” What were they like? Large and prominent, they were adapted to improve their ability to see in flight, a key detail for an aerial predator.
Meganeura is frequently compared to the modern dragonflies due to its general appearance, with an elongated body, broad wings adapted for flight, and prominent compound eyes. However, despite these superficial similarities, it does not belong to the group of current dragonflies, scientifically known as Odonatabut to an ancestral lineage classified as Protodonata.
This taxonomic detail shows that, although they share a similar appearance, the differences between both groups are profound and represent evolutionary stages separated by millions of years.
Scientific names emphasize these distinctions. Meganeura is a snowflakethe type species of the genus, is a sample of the characteristics that defined the group Protodonatawith wide wings and a wingspan of up to 70 centimeters.
Modern dragonflies, on the other hand, include families such as Libellulidaewith significantly smaller members and adapted to environments other than the humid Carboniferous swamps. These differences in nomenclature reflect not only their evolutionary divergences, but also the adaptations that each group developed in response to their specific environments.
About your dietthe researcher explained that it was carnivore and was based on small organismstaking advantage of its flight ability to hunt. According to the information read in the exhibition at the MEF, this species also fed on other insects. “At that time they did not eat rodents because there were none, mammals did not yet exist and, probably, they would eat the occasional small reptile or amphibians that were just conquering this terrestrial environment. That is, it ate very small organisms,” he explained.
At the time, the planet was covered by vast swamp forests that provided a unique environment for creatures like Meganeura. These landscapes, formed by giant ferns, lycopodia and horsetails, were a constant in a hot and humid world, without marked seasons. About this, Pagani elaborated: “the time in which Meganeura lived, in the Carboniferous, proliferated large forests and wet swamps. “The temperatures were probably quite a bit higher.” These conditions allowed not only the proliferation of exuberant flora, but also the appearance of organisms of extraordinary sizes.
One of the most notable factors of this period was the high concentration of oxygen in the atmospherewhich reached levels above 30%, significantly higher than the current 21%. This excess of oxygen was decisive for the gigantism that characterized many Carboniferous organisms, including insects.
Pagani noted that “at that time there was an excess of oxygen in the atmosphere. “Probably up to more than 30%, 50% higher than the current level.” This abundance facilitated the efficiency of the respiratory system of this giant flying insect, allowing it to reach unimaginable proportions compared to modern insects.
In addition to lush vegetation and high oxygen levels, the Carboniferous offered a prey-rich ecosystem, ideal for an aerial predator like Meganeura. “With such a wingspan, it would be very rare for it to live in very wooded environments or in closed forests, but rather, it is assumed, lived in slightly more open habitats to be able to move comfortably,” explained the scientist.
The gigantism of insects during the Carboniferous, such as Meganeura, generated an intense debate in the scientific community. One of the most accepted theories maintains that the high levels of oxygen in the atmosphere, which exceeded 30%—50% more than today—allowed the tracheal respiratory systems of insects to be more efficient, facilitating their growth through extraordinary sizes. However, more recent studies question this exclusive explanation, proposing that insects could also have developed physiological adaptations that did not depend exclusively on environmental oxygen.
Another factor under discussion is the impact of the absence of aerial predators in that period. Without birds or hunting vertebrates, the skies were a safe environment for creatures like Meganeura, which could have favored the development of large sizes. Furthermore, the warm conditions and swampy forests of the Carboniferous offered an ideal habitat for them to thrive. Although these hypotheses are widely supported, they leave open discussion in paleontology.
The first fossil remains of Meganeura were discovered in 1880 in Commentry, Francea site rich in strata from the Carboniferous period. These rock layers preserved the features of this winged creature in remarkable detail, providing a glimpse into the giant insects’ distant past. In 1885, the French paleontologist Charles Brongniart studied these fossils and was the one who first described the genus, baptizing it Meganeura, which means “large ribs” in reference to the complex network of veins that characterized its wings.
Over time, other notable fossils were found that expand knowledge about these creatures. In 1979, a significant specimen was found at Bolsover, Derbyshire, Englandwhich confirmed that these insects inhabited what is now known as Europe. The original holotype is preserved in the Paris Natural History Museumwhere it continues to be the subject of scientific studies and a centerpiece in the paleontology of prehistoric insects.
Furthermore, in 1940, a discovery in Oklahoma, USArevealed the largest insect wing known to date, belonging to a related species, Meganeura americana. This fossil is preserved in the Harvard Museum of Natural Historyshow the relevance of these findings in different continents.
