A 310-year-old beetle on a continent where it shouldn’t be

An investigation reveals for the first time the presence in Africa of a specimen of a family of beetles never before seen on that continent.

The study is the work of an international team led from the Higher Council for Scientific Research (CSIC) in Spain.

The work describes a specimen preserved in copal (the first step of the resin before becoming amber) of a beetle specimen of the Jacobsoniidae family that is more than 300 years old and shows the 3D virtual reconstruction using innovative techniques in the Desy synchrotron. from Hamburg in Germany.

The specimen described in this work belongs to the species Derolathrus cavernicolus, which until now had only been seen in Florida, Hawaii, Barbados and Japan. “The unusual thing about this discovery is that technically, the family still does not live in Africa, since the specimen analyzed dates back about 310 years, being preserved in copal from Tanzania, as explained by David Peris, a researcher at the Botanical Institute of Barcelona (IIB), joint center of the CSIC and the Barcelona City Council.

The copal is the first step of fossilization of the resin before becoming amber. “Therefore, this discovery shows that the Jacobsoniidae family inhabited East Africa a little over 300 years ago, but not today, so perhaps it is extinct today, like in many other parts of the planet.” , says Peris, co-author of the study. This leads one to think that they were a more widely distributed family in the past than they are today.

The research has had the collaboration of the researcher Mónica M. Solórzano-Kraemer, from the Senckenberg Research Institute and Museum of Natural History in Frankfurt, Germany. Solórzano-Kraemer has collaborated in the virtual reconstruction of the specimen’s surface with the Desy synchrotron in Hamburg. “This is an example of the relevance of studying copal and resins to discover new indicators of biodiversity loss, in some cases perhaps due to human activity,” says the researcher.

Detail of the 3D reconstruction of the beetle specimen found in copal from Tanzania. (Image: Synchrotron Desy)

An unknown beetle family in Africa

Jacobsons are a small family of beetles hitherto unknown on the African continent. This family has 24 current species that inhabit tropical and subtropical areas, mainly on islands. They are very small species; they barely reach 2 millimeters in length. “This makes them especially difficult to detect, whether they are current specimens or fossils,” says Peris. “They tend to inhabit leaf litter and decaying wood,” he adds.

Only four fossil species are known in this family, all of them described in amber (fossilized resin). Three of these species have been described in amber dating back almost 100 million years from France and Myanmar. The fourth is a species described in amber from about 40 million years ago from the Baltic.

The study is titled “First record of Jacobsoniidae (Coleoptera) on the African continent in Holocene copal from Tanzania: biogeography since the Cretaceous”. And it has been published in the academic journal Scientific Reports. (Source: CSIC)