Earliest known fossil mosquito from Lebanon suggests males were bloodsuckers

Updatetime: 2023-12-05

Dany Azar, from the Nanjing Institute of Geology and Paleontology, Chinese Academy of Sciences (NIGPAS) and the Lebanese University, has reported in Current Biology on December 4, 2023, which have found the earliest known fossil mosquito in Lower Cretaceous amber from Lebanon. What’s more, the well-preserved insects are two males of the same species with piercing mouthparts, suggesting they likely sucked blood.

“Lebanese amber is to date the oldest amber with intensive biological inclusions and it is a very important material as its formation is contemporaneous with the appearance and beginning of radiation of flowering plants, with all what follows of co-evolution between pollinators and flowering plants” said D. Azar.

Among modern-day mosquitos, only females are hematophagous, meaning that they use piercing mouth parts to feed on the blood of people and other animals.

“Molecular dating suggested that the family Culicidae arose during the Jurassic, but previously the oldest record was mid-Cretaceous,” said André Nel of the  National Museum of Natural History of Paris (Muséum National d’Histoire Naturelle de Paris). “Here we have one from the early Cretaceous, about 30 million years before.”

The Culicidae family of arthropods includes more than 3,000 species of mosquitoes. Female mosquitoes are notorious for their blood-feeding ways, which has made them a major vector for spreading infectious diseases. Hematophagy in insects is thought to have arisen as a shift from piercing-sucking mouthparts used to extract plant fluids. For example, blood-sucking fleas likely arose from nectar-feeding insects. But the evolution of blood-feeding has been hard to study in part due to gaps in the insect fossil record.

In the new study, researchers describe two male mosquitos with piercing mouthparts, including an exceptionally sharp, triangular mandible and elongated structure with small, toothlike denticles. The new findings suggest that male mosquitoes in the past fed on blood as well, according to the researchers. They also help to narrow the “ghost-lineage gap” for mosquitoes, they say.

They report that the mosquitos’ preservation in amber extends the definitive occurrence of the mosquito family of insects into the early Cretaceous. It also suggests the evolution of hematophagy was more complicated than had been suspected, with hematophagous males in the distant past.

In future work, Nel says they want to learn more about the 'utility' of having hematophagy in Cretaceous male mosquitos. They’re also curious to explore “why this no longer exists,” he says.

This work was supported by the National Natural Science Foundation of China..

Reference: Dany Azar, Andre Nel, Diying Huang, Michael S. Engel, The earliest fossil mosquito, Current Biology (2023), https://doi.org/10.1016/j.cub.2023.10.047.

Dorsal view of male mosquito in amber.

Detail of mouthparts using a confocal microscope; scale bar, 10 μm

Age recovery of fossil mosquito in Lower Cretaceous amber from Lebanon




LIU Yun, Propagandist

Email: yunliu@nigpas.ac.cn

Nanjing Institute of Geology and Palaeontology, Chinese Academy of Sciences

Nanjing, Jiangsu 210008, China