A remarkable discovery in amber from Myanmar’s Kačjin state has unveiled a new species of wasp from the mesozoic period, named Sirenobethylus charybdis. The amber preserved 16 female specimens in exquisite detail, allowing scientists to study their anatomy using advanced technologies, including microscopic observations and CT scans.

Predator or Parasite? The Wasp’s Unique Trap

research published in BMC Biology details the structure and function of a unique apparatus found on the wasp’s abdomen. This structure consists of three movable flaps covered in bristles,bearing a striking resemblance to the trapping mechanism of Venus flytraps (Dionaea Muscipula).

However, unlike the Venus flytrap, Sirenobethylus charybdis did not use this apparatus to kill its prey. Instead, it used the trap to capture flying insects, into which it would then lay its eggs. The captured insect served as a “living incubator” for the wasp larvae, which would then develop as parasites, ultimately consuming and destroying their host.

this abdominal apparatus is unprecedented throughout the history of Mesozoic insect research and nothing like this has been documented even in contemporary insects.
Qiong Wu, Capital Normal University, Beijing, National Geographic

Mythological Naming: Sirens, Sea Monsters, and Parasitism

The scientific name of the wasp, Sirenobethylus charybdis, draws inspiration from Greek mythology. The genus name, Sirenobethylus, alludes to the sirens who lured sailors to their doom with enchanting songs, reflecting the wasp’s method of attracting prey to its trap. The suffix “bethylus” refers to the Bethylidae family,known for their parasitic egg-laying behavior.

The species name, Charybdis, references the sea monster Charybdis, famous for creating whirlpools that swallowed ships. The scientists likely chose this name as the wasp’s abdominal apparatus,with its three moving valves,reminded them of Charybdis’s “absorbing” mechanism.

A Unique Find in Cretaceous Amber

The amber from Kačjin state is world-renowned for its rich biodiversity of fossils from the mid-Cretaceous period. The local ecosystems, likely tropical forests, provided an ideal environment for the evolution of diverse insect forms, including this unique wasp.

Lars Vilhelmsen,co-author of the study,described his initial reaction to the discovery:

When I looked at the first specimen,I noticed an extension at the end of my stomach and thought it must be an air bubble.Air bubbles appear around the fossils in amber quite often. but then I looked at several othre specimens. what I saw was part of the wasp body.
Lars Vilhelmsen,CNN

Convergent Evolution and Insect Diversity in the Cretaceous Period

The comparison of this prehistoric wasp to the Venus flytrap highlights the concept of convergent evolution. This is the process were similar traits or structures evolve independently in different species that are not closely related. The trapping mechanism found in both the carnivorous plant and the wasp demonstrates this phenomenon.

This discovery, along with other recent studies on wing reduction in insects, suggests that the cretaceous period was a pivotal time for insect evolution. During this era,insects developed refined strategies that continue to surprise and challenge our understanding of evolutionary processes.