Burmese amber

Dwarfs under dinosaur legs: 99-million-year-old millipede discovered in Burmese amber

A 3D reconstruction of the fossil allowed for the description of an entirely new suborder

The newly described millipede (*Burmanopetalum inexpectatum*) rendered using 3D X-ray microscopy. Image by Leif Moritz.

Even though we are led to believe that during the Cretaceous the Earth used to be an exclusive home for fearsome giants, including carnivorous velociraptors and arthropods larger than a modern adult human, it turns out that there was still room for harmless minute invertebrates measuring only several millimetres.

Such is the case of a tiny millipede of only 8.2 mm in length, recently found in 99-million-year-old amber in Myanmar. Using the latest research technologies, the scientists concluded that not only were they handling the first fossil millipede of the order (Callipodida) and also the smallest amongst its contemporary relatives, but that its morphology was so unusual that it drastically deviated from its contemporary relatives.

As a result, Prof. Pavel Stoev of the National Museum of Natural History (Bulgaria) together with his colleagues Dr. Thomas Wesener and Leif Moritz of the Zoological Research Museum Alexander Koenig (Germany) had to revise the current millipede classification and introduce a new suborder. To put it in perspective, there have only been a handful of millipede suborders erected in the last 50 years. The findings are published in the open-access journal ZooKeys.

To analyse the species and confirm its novelty, the scientists used 3D X-ray microscopy to ‘slice’ through the Cretaceous specimen and look into tiny details of its anatomy, which would normally not be preserved in fossils. The identification of the millipede also presents the first clue about the age of the order Callipodida, suggesting that this millipede group evolved at least some 100 million years ago. A 3D model of the animal is also available in the research article.

Curiously, the studied arthropod was far from the only one discovered in this particular amber deposit. On the contrary, it was found amongst as many as 529 millipede specimens, yet it was the sole representative of its order. This is why the scientists named it Burmanopetalum inexpectatum, where “inexpectatum” means “unexpected” in Latin, while the generic epithet (Burmanopetalum) refers to the country of discovery (Myanmar, formerly Burma).

Lead author Prof. Pavel Stoev says:

We were so lucky to find this specimen so well preserved in amber! With the next-generation micro-computer tomography (micro-CT) and the associated image rendering and processing software, we are now able to reconstruct the whole animal and observe the tiniest morphological traits which are rarely preserved in fossils. This makes us confident that we have successfully compared its morphology with those of the extant millipedes. It came as a great surprise to us that this animal cannot be placed in the current millipede classification. Even though their general appearance have remained unchanged in the last 100 million years, as our planet underwent dramatic changes several times in this period, some morphological traits in Callipodida lineage have evolved significantly.

The newly described millipede seen in amber. Image by Leif Moritz.

Co-author Dr. Thomas Wesener adds:

“We are grateful to Patrick Müller, who let us study his private collection of animals found in Burmese amber and dated from the Age of Dinosaurs. His is the largest European and the third largest in the world collection of the kind. We had the opportunity to examine over 400 amber stones that contain millipedes. Many of them are now deposited at the Museum Koenig in Bonn, so that scientists from all over the world can study them. Additionally, in our paper, we provide a high-resolution computer-tomography images of the newly described millipede. They are made public through MorphBank, which means anyone can now freely access and re-use our data without even leaving the desk.”

Leading expert in the study of fossil arthropods Dr. Greg Edgecombe (Natural History Museum, London) comments:

“The entire Mesozoic Era – a span of 185 million years – has until now only been sampled for a dozen species of millipedes, but new findings from Burmese amber are rapidly changing the picture. In the past few years, nearly all of the 16 living orders of millipedes have been identified in this 99-million-year-old amber. The beautiful anatomical data presented by Stoev et al. show that Callipodida now join the club.”

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Original source:

Stoev P, Moritz L, Wesener T (2019) Dwarfs under dinosaur legs: a new millipede of the order Callipodida (Diplopoda) from Cretaceous amber of Burma. ZooKeys 841: 79-96. https://doi.org/10.3897/zookeys.841.34991

Scientists discover over 450 fossilised millipedes in 100-million-year-old amber

Since the success of the Jurassic Park film series, it is widely known that insects from the Age of the Dinosaurs can be found exceptionally well preserved in amber, which is in fact fossilised tree resin.

Especially diverse is the animal fauna preserved in Cretaceous amber from Myanmar (Burma). Over the last few years, the almost 100-million-year-old amber has revealed some spectacular discoveries, including dinosaur feathers, a complete dinosaur tail, unknown groups of spiders and several long extinct groups of insects.

However, as few as three millipede species, preserved in Burmese amber, had been found prior to the study of Thomas Wesener and his PhD student Leif Moritz at the Zoological Research Museum Alexander Koenig – Leibniz Institute for Animal Biodiversity (ZFMK). Their research was recently published in the open-access journal Check List.

One of the newly discovered fossilised millipedes. Photo by Dr Thomas Wesener.

Having identified over 450 millipedes preserved in the Burmese amber, the scientists confirmed species representing as many as 13 out of the 16 main orders walking the Earth today. The oldest known fossils for half of these orders were found within the studied amber.

The researchers conducted their analysis with the help of micro-computed tomography (micro-CT). This scanning technology uses omni-directional X-rays to create a 3D image of the specimen, which can then be virtually removed from the amber and digitally examined.

The studied amber is mostly borrowed from private collections, including the largest European one, held by Patrick Müller from Käshofen. There are thought to be many additional, scientifically important specimens, perhaps even thousands of them, currently inaccessible in private collections in China.

Over the next few years, the newly discovered specimens will be carefully described and compared to extant species in order to identify what morphological changes have occurred in the last 100 million years and pinpoint the speciation events in the millipede Tree of Life. As a result, science will be finally looking at solving long-standing mysteries, such as whether the local millipede diversity in the southern Alps of Italy or on the island of Madagascar is the result of evolutionary processes which have taken place one, ten or more than 100-million years ago.

According to the scientists, most of the Cretaceous millipedes found in the amber do not differ significantly from the species found in Southeast Asia nowadays, which is an indication of the old age of the extant millipede lineages.

On the other hand, the diversity of the different orders seems to have changed drastically. For example, during the Age of the Dinosaurs, the group Colobognatha – millipedes characterised by their unusual elongated heads which have evolved to suck in liquid food – used to be very common. In contrast, with over 12,000 millipede species living today, there are only 500 colobognaths.

Another curious finding was the discovery of freshly hatched, eight-legged juveniles, which indicated that the animals lived and reproduced in the resin-producing trees.

“Even before the arachnids and insects, and far ahead of the first vertebrates, the leaf litter-eating millipedes were the first animals to leave their mark on land more than 400-million-years ago,” explain the scientists. “These early millipedes differed quite strongly from the ones living today – they would often be much larger and many had very large eyes.”

The larger species in the genus Arthropleura, for example, would grow up to 2 m (6.5 ft) long and 50-80 cm (2-3 ft) wide – the largest arthropods to have ever crawled on Earth. Why these giants became extinct and those other orders survived remains unknown, partly because only a handful of usually badly preserved fossils from the whole Mesozoic era (252-66-million years ago) has been retrieved. Similarly, although it had long been suspected that the 16 modern millipede orders must be very old, a fossil record to support this assumption was missing.

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Original source:

Wesener T, Moritz L (2018) Checklist of the Myriapoda in Cretaceous Burmese amber and a correction of the Myriapoda identified by Zhang (2017). Check List 14(6): 1131-1140. https://doi.org/10.15560/14.6.1131

The ‘Star dust’ wasp is a new extinct species named after David Bowie’s alter ego

During her study on fossil insects of the order Hymenoptera at China’s Capitol Normal University, student Longfeng Li visited the Smithsonian National Museum of Natural History, Washington, carrying two unidentified wasp specimens that were exceptionally well-preserved in Burmese amber. This type of fossilized tree resin is known for the quality of the fossil specimens which can be preserved inside it. Being 100 million years old, they provide an incredible view into the past.

The subsequent analysis of the specimens revealed that both represent species new to science. Furthermore, one of the wasps showed such amazing similarities to a modern group of wasps that it was placed in a currently existing genus, Archaeoteleiawhich has long been considered as an ancient lineage. The species are described in a study published in the open access Journal of Hymenoptera Research.

However, Archaeoteleia has changed since the times when the ancient wasp got stuck on fresh tree resin. The authors note that “a novice might not recognize the characters that unite the fossil with extant species”. For instance, the modern wasp species of the genus show visibly longer antennal segments and a different number of teeth on the mandible when compared to the fossil. In turn, the description of the new extinct species enhances the knowledge about living species by highlighting anatomical structures shared by all species within the genus.

This fossil wasp with living relatives received quite a curious name, Archaeoteleia astropulvis. The species name, astropulvis, translates from Latin to ‘star dust’. The discoverers chose the name to refer to both “the ancient source of the atoms that form our planet and its inhabitants”, as well as to commemorate the late David Bowie’s alter ego – Ziggy Stardust.

Unlike the Star dust wasp, the second new species belongs to a genus (Proteroscelio) known exclusively from Cretaceous fossils. Likewise, it is a tiny insect, measuring less than 2mm in length. It also plays an important role in taxonomy by expanding the anatomical diversity known from this extinct genus.

The authors conclude that their discovery, especially the Star dust wasp and its placement in an extant genus, where it is the only fossil species, “exemplifies the importance of understanding the extant fauna of a taxon to interpret fossils”.

“Such union of fossil and extant morphologies is especially illuminating and requires examination of both kinds of specimens,” they add.

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Original source:

Talamas EJ, Johnson NF, Buffington ML, Dong R (2016) Archaeoteleia Masner in the Cretaceous and a new species of Proteroscelio Brues (Hymenoptera, Platygastroidea). In: Talamas EJ, Buffington ML (Eds) Advances in the Systematics of Platygastroidea. Journal of Hymenoptera Research 56: 241-261. https://doi.org/10.3897/jhr.56.10388