Key fossils discovered in Morocco to understand the migrations of organisms between Europe and Africa 120 million years ago
An international team of paleontologists and geologists made up of researchers from the Faculty of Earth Sciences of the UB and IRBio and the University of Oujda, has identified for the first time in Morocco several species of charophytes —fossil aquatic plants— that date back about 120 million years (Aptian, geological period, of the Lower Cretaceous). Some of the species found have been described in Europe and Asia or in North America, but never in Africa, this discovery fills an important gap in knowledge about the distribution of these organisms and provides key information to reconstruct ancient landscapes and climates. The study is also key to understanding the biogeography of charophytes in the geological past.
Charophytes, a tool for dating rocks and learning about past environments
Charophytes are a group of multicellular green algae that live in fresh or slightly brackish waters on all continents, except Antarctica. In the past, these plants left calcified remains that today serve as guide fossils to date continental sediments. Current species live under very specific environmental conditions, and changes in flowers help to understand how lakes and aquatic ecosystems evolve.
The study, published in the journal Cretaceous Research, describes seven species, including Echinochara lazarii, Atopochara trivolvis and several varieties of the genus Clavator. Some of these species were already known in the Iberian Peninsula and Tunisia, but had never been found in the western domain of the Moroccan Atlas.
Based on this fact, charophyte fossils are commonly studied to learn about past environmental conditions. In addition, their reproductive structures evolve rapidly (on a geological scale), they are excellent indicators for determining the age of the rock and establishing correlations between areas as distant as the Iberian Peninsula and Central Asia.
Understanding the biogeography of charophytes during the Aptian
Of the species identified, two are particularly relevant: Clavator grovesii var. jiuquanensis and Clavator grovesii var. corrugatus. The two species are evolutionary varieties of the species Clavator grovesii, which means that one variety is the result of the evolution of the previous one and intermediate morphologies can be found between them; until now, no variety of the species had been found in Africa.
According to Jordi Pérez Cano, researcher at the University of Barcelona and IRBio and co-author of the article, “These varieties have been used as markers to determine the age of the rock, but until now Clavator grovesii variety jiuquanensis had only been found in Europe and Asia, while Clavator grovesii variety corrugatus had only been described in the Iberian Peninsula and North America, but never in Africa, making it more difficult to correlate the record from North Africa with that of Eurasia or North America. In addition, it is unusual for them to appear together: usually one or the other appears. Until now, they had only been described together in the Algarve, in a study of their own in 2023.“
The researcher also shares an anecdote: “When Hamid sent me a first series of photographs of the charophytes, I said to him: “Finally, you find Echinochara lazarii in Morocco!” It was strange that you didn't find it”. This species is found in very similar rocks of the same age in the Peninsula and in Tunisia, its absence was a strange gap”.
In addition to the species mentioned, the charophyte association includes other species, such as three evolutionary varieties of Clavator harrisii and one of Atopochara trivolvis.
The attached images show all these species.
Above: paleogeographic map of Europe and North Africa during the Aptian. The marked area corresponds to the area where Clavator grovesii var. jiuquanensis and Clavator grovesii var. corrugatus have been found coexisting, which is the key to dating the rocks of Morocco. MA: Moroccan Highs; TA: Tunisian Highs; Al: Algarve; CB: Cantabrian Basin; IC: Iberian System. Below: Electron microscope images of charophyte fruiting bodies found in the Moroccan Atlas Image modified from the original article (Haddoumi et al. 2026).
These aquatic plants are key fossils for dating rocks and understanding ancient ecosystems.
The Aptian, a key period in Earth’s history
The results are important because there are few systematic studies of charophytes from the Aptian. This is possibly because during the Aptian there was a rise in sea levels and many of the areas that were previously continental became marine areas. It also coincides with a period of climatic instability that is well studied in marine rocks, but not so much in continental rocks due to the lack of records. Therefore, any study is especially valuable due to the lack of knowledge.
As mentioned above, the flora found in the Atlas of Morocco is identical to that described in the Algarve for the same period in 2023. “This indicates that the connection between Europe and Africa was especially important in this area, being more complicated in other regions further east. I believe that in the coming years, the in-depth study of these two regions can provide us with surprises and unexpected complementary data on what the charophyte communities of this period were like, how they evolved and how the lakes and continental ecosystems evolved as a result of this climatic instability,” explains Jordi Pérez.
The research is published in the open access journal Cretaceous Research, thanks to the agreement between the University of Barcelona and the Elsevier publishing house.
Reference: Haddoumi, H., Pérez-Cano, J., Chennouf, R., Amakrane, J., & Mamoun, S. M. (2026). New findings of lower Aptian charophytes from the Southern High Plateaus (Eastern Meseta, Morocco): biostratigraphic and biogeographic significance. Cretaceous Research 179, 106262.