NEWS - Three new species of plate-thigh beetles that lived in the mid-Cretaceous show long-term evolutionary stasis with the same morphology as their living relatives. The three species, Eucinetus debilispinus, E. panghongae and E. zhenhuai, show that the genus has remained consistent for more than 100 million years.
Researchers from the Nanjing Institute of Geology and Palaeontology, the University of Bristol, and American Museum of Natural History in New York describe fossils from mid-Cretaceous Kachin amber that all represent the genus Eucinetus germar that is still alive today.
The study provides an example of long-term evolutionary stasis with a subcortical lifestyle. It further suggests the role of stable cryptic microhabitats in the persistence of some lineages over long geological timescales.
Many of the species in this genus are associated with leaf litter or decaying wood microhabitats, species living in relatively stable microenvironments and feeding on a consistent set of resources from these stable habitats, such as wood-decomposing fungi.
The global environment has undergone significant changes in flora, fauna, and general climate over thousands of years, but these hidden microhabitats have remained constant, allowing species specialized in microhabitats to survive with minimal change over long episodes of geological history.
Eucinetus stands in stark contrast to other lineages that lead more exposed lives and have experienced evolutionary change and even extinction, although the boundaries of these microhabitats have limitations such as the relatively ephemeral nature of wood that is eventually exhausted through decay and the need for movement and hazards.
Original research
Yan-Da Li, Michael S. Engel, Di-Ying Huang, Chen-Yang Cai (2024). Three new species of the extant genus Eucinetus from mid-Cretaceous amber of northern Myanmar (Coleoptera: Eucinetidae). Zootaxa: 5492 (2): 214–230. DOI:10.11646/zootaxa.5492.2.4
Researchers from the Nanjing Institute of Geology and Palaeontology, the University of Bristol, and American Museum of Natural History in New York describe fossils from mid-Cretaceous Kachin amber that all represent the genus Eucinetus germar that is still alive today.
The study provides an example of long-term evolutionary stasis with a subcortical lifestyle. It further suggests the role of stable cryptic microhabitats in the persistence of some lineages over long geological timescales.
Many of the species in this genus are associated with leaf litter or decaying wood microhabitats, species living in relatively stable microenvironments and feeding on a consistent set of resources from these stable habitats, such as wood-decomposing fungi.
The global environment has undergone significant changes in flora, fauna, and general climate over thousands of years, but these hidden microhabitats have remained constant, allowing species specialized in microhabitats to survive with minimal change over long episodes of geological history.
Eucinetus stands in stark contrast to other lineages that lead more exposed lives and have experienced evolutionary change and even extinction, although the boundaries of these microhabitats have limitations such as the relatively ephemeral nature of wood that is eventually exhausted through decay and the need for movement and hazards.
Original research
Yan-Da Li, Michael S. Engel, Di-Ying Huang, Chen-Yang Cai (2024). Three new species of the extant genus Eucinetus from mid-Cretaceous amber of northern Myanmar (Coleoptera: Eucinetidae). Zootaxa: 5492 (2): 214–230. DOI:10.11646/zootaxa.5492.2.4