Filamentous cyanobacteria preserved in masses of fungal hyphae from the Triassic of Antarctica

• Published in: PeerJ
• Main Authors: Carla J. Harper, Edith L. Taylor, Michael Krings
• Format: Article in Journal/Newspaper
• Language: English
• Published: PeerJ Inc. 2020
• Subjects: Endochaetophora antarctica; Fungal reproduction; Lichen; Mesozoic; Mucoromycota; Oscillatoriaceae; Medicine; R; Biology (General); QH301-705.5; Transantarctic Mountains; Antarc*; Antarctica
• Online Access: https://doi.org/10.7717/peerj.8660; https://doaj.org/article/191b482ce80a49fb959632c6c6774d72

Permineralized peat from the central Transantarctic Mountains of Antarctica has provided a wealth of information on plant and fungal diversity in Middle Triassic high-latitude forest paleoecosystems; however, there are no reports as yet of algae or cyanobacteria. The first record of a fossil filamentous cyanobacterium in this peat consists of wide, uniseriate trichomes composed of discoid cells up to 25 µm wide, and enveloped in a distinct sheath. Filament morphology, structurally preserved by permineralization and mineral replacement, corresponds to the fossil genus Palaeo-lyngbya, a predominantly Precambrian equivalent of the extant Lyngbya sensu lato (Oscillatoriaceae, Oscillatoriales). Specimens occur exclusively in masses of interwoven hyphae produced by the fungus Endochaetophora antarctica, suggesting that a special micro-environmental setting was required to preserve the filaments. Whether some form of symbiotic relationship existed between the fungus and cyanobacterium remains unknown.