J Syst Evol

• Research Articles •    

Miocene Ethiopian amber: A new source of fossil cryptogams

Valentine Bouju1*, Kathrin Feldberg2, Ulla Kaasalainen2, Alfons Schäfer‐Verwimp3, Lars Hedenäs4, William R. Buck5, Bo Wang6, Vincent Perrichot1, and Alexander R. Schmidt2   

  1. 1 Univ Rennes, CNRS, Géosciences Rennes, UMR 6118, 263 avenue du Général Leclerc, 35000 Rennes, France
    2 Department of Geobiology, University of Göttingen, Goldschmidtstraße 3, 37077 Göttingen, Germany
    3 Mittlere Letten 11, 88634 Herdwangen‐Schönach, Germany
    4 Department of Botany, Swedish Museum of Natural History, Box 50007, 104 05 Stockholm, Sweden
    5 Institute of Systematic Botany, The New York Botanical Garden, Bronx, New York NY 10458‐5126, USA
    6 State Key Laboratory of Palaeobiology and Stratigraphy, Nanjing Institute of Geology and Palaeontology and Center for Excellence in Life and Palaeoenvironment, Chinese Academy of Sciences, 39 East Beijing Road, 210008 Nanjing, China
  • Received:2020-12-15 Accepted:2021-05-14 Online:2021-05-17

Abstract: Amber is renowned for the exceptional preservation state of its inclusions, allowing detailed morphological analysis and providing relevant environmental, palaeoecological, geographical, and geological information. Amber deposits are predominantly known from North America, Europe, and Asia, and are considered to be rare on the continents that formed Gondwana. The recent discovery of fossiliferous amber deposits in Ethiopia, therefore, provides an inimitable opportunity to close gaps in the fossil record of African terrestrial biota and to study organisms which are otherwise rare in the fossil record. Here we show that diverse cryptogams are preserved in highest fidelity in Miocene Ethiopian amber. We describe gametophyte fragments of four liverworts: Thysananthus aethiopicus sp. nov. (Porellales, Lejeuneaceae), Lejeunea abyssinicoides sp. nov. (Porellales, Lejeuneaceae), Frullania shewanensis sp. nov. (Porellales, Frullaniaceae), and Frullania palaeoafricana sp. nov. (Porellales, Frullaniaceae). Furthermore, we describe a pleurocarpous moss of the extant genus Isopterygium (Hypnales, Pylaisiadelphaceae) and a lichen representing the order Lecanorales. These new specimens represent the first amber fossils of liverworts, mosses, and lichens from the African continent and render Ethiopian amber as one of the few worldwide amber deposits preserving bryophytes (mosses and liverworts) or lichens. Fossil species of Thysananthus were recorded in Eocene Baltic and Oligocene Bitterfeld as well as Miocene Dominican and probably also Miocene Mexican ambers. Fossils that can unequivocally be assigned to Lejeunea have only been found in Dominican amber so far. Neotropical ambers contain only one taxon of Frullania to date, while the genus is most diverse in Baltic, Bitterfeld, and Rovno ambers, formed in temperate regions. The new fossils support a tropical to subtropical origin of Ethiopian amber. The new African liverwort fossils are included in an updated list of leafy liverworts described from worldwide Cenozoic ambers to date.

Key words: Africa, amber, lichens, liverworts, Miocene, mosses