Fungalpedia – Note 162 Chaetosphaerites (Fossil Fungi)


Chaetosphaerites Felix 1894 (Fossil).

Citation when using this data: Saxena RK & Hyde KD. 2024 (in prep) – Fungalpedia, Fossil Fungi. 

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Classification: Phragmosporae, Fossil Fungi. 

Felix (1894) instituted Chaetosphaerites from the Eocene (56–34 mya) sediments of Perekeschkul, near Baku, Azerbaijan. Felix (1894) stated that some silicified spores are characterized particularly by the dark brown middle and pale brown end cells. Since the boundaries of the respective colours coincide exactly with the sharp delimitations of the individual segments, it is probably not justified to assume that the differences in shade only resulted from the state of preservation. It is unlikely, particularly in view of the minute size of the objects, for differences to occur in the state of preservation of the individual parts. Additionally, within the genera Chaetosphaeria, Lophiostoma, Massaria, and Melanomma there occur many species in which only the middle cells are of darker colour – generally dark brown or blackish-than the end cells which often appear almost colourless. The shape of the sporidia is strongly obtuse and spindle-shaped, almost like that of a cylinder with rounded ends. They probably consist of 4 segments, but the midmost septum is not clearly visible due to the dark colouration of this area. The length is 0.0238 mm (23.8 μm), the width is 0.0085 mm (8.5 μm). The two median, dark-coloured cells are larger than the other two; their combined length is 0.0148 mm (14.8 μm).”

Synonym: Cannanorosporonites Ramanujam & Rao, 

Type species: Chaetosphaerites bilychnis Felix.




Figure 1  Chaetosphaerites bilychnis. Scale bar = 5 μm. Redrawn from Felix (1894).



Felix J. 1894 – Studien über fossile Pilze. Zeitschrift der Deutschen Geologischen Gesellschaft 46, 269–280. 

Ramanujam CGK, Rao. KP. 1978 – Fungal spores from the Neogene strata of Kerala in South India, 291–304. In: Bharadwaj D.C. et al. (Editors) – Proceedings of the 4th International Palynological Conference, Lucknow 1976–77, Volume 1, Birbal Sahni Institute of Palaeobotany, Lucknow.


Entry by

Ramesh K. Saxena, Birbal Sahni Institute of Palaeosciences, Lucknow, India


(Edited by Kevin D. Hyde, Samaneh Chaharmiri-Dokhaharani, & Achala R. Rathnayaka)