Problems related to the taxonomic placement of incompletely preserved amber fossils: transfer of the Paleogene liverwort Cylindrocolea dimorpha (Cephaloziellaceae) to the extant Odontoschisma sect. Iwatsukia (Cephaloziaceae)

Feldberg, Kathrin; Vana, Jiri; Schäfer-Verwimp, Alfons; Krings, Michael; Gröhn, Carsten; Schmidt, Alexander R. und Heinrichs, Jochen (2017): Problems related to the taxonomic placement of incompletely preserved amber fossils: transfer of the Paleogene liverwort Cylindrocolea dimorpha (Cephaloziellaceae) to the extant Odontoschisma sect. Iwatsukia (Cephaloziaceae). In: Fossil Record, Bd. 20, Nr. 2: S. 147-157

Abstract

A revision of the Baltic and Bitterfeld amber fossils assigned to Cylindrocolea dimorpha (Cephaloziellaceae) has yielded evidence of the presence of multicellular, bifid underleaves, which have not previously been reported for this species and conflict with the current circumscription of the family. We transfer the fossil species to Odontoschisma (sect. Iwatsukia) and propose the new combination O. dimorpha of the Cephaloziaceae. Characteristics of the fossil include an overall small size of the plant, entire-margined, bifid leaves and underleaves, more or less equally thickened leaf cell walls, ventral branching that includes stoloniform branches with reduced leaves, and the lack of a stem hyalodermis and gemmae. Placement of the fossil in Cephaloziaceae profoundly affects divergence time estimates for liverworts based on DNA sequence variation with integrated information from the fossil record. Our reclassification concurs with hypotheses on the divergence times of Cephaloziaceae derived from DNA sequence data that provide evidence of a late Early Cretaceous to early Eocene age of the Odontoschisma crown group and an origin of O. sect. Iwatsukia in the Late Cretaceous to Oligocene.

• Dokumententyp: Zeitschriftenartikel
• Fakultät: Geowissenschaften > Department für Geo- und Umweltwissenschaften
• Fakultätsübergreifende Einrichtungen: GeoBio-Center
• Themengebiete: 500 Naturwissenschaften und Mathematik > 500 Naturwissenschaften ; 500 Naturwissenschaften und Mathematik > 550 Geowissenschaften, Geologie
• ISSN: 2193-0066
• Sprache: Englisch