Fungalpedia – Note 181, Polyhyphaethyrites (Fossil Fungi)


Polyhyphaethyrites R. Srivast. & R.K. Kar.

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

Index Fungorum, Facesoffungi, MycoBank, GenBank, Fig. 1

Classification: Microthyriales. Dothideomycetes, Fossil Ascomycota

The monotypic fossil genus, Polyhyphaethyrites, was described by Srivastava & Kar (2004) from the Deccan Intertrappean Beds (Palaeocene, 66–56 mya) of Mohgaon Kalan, Chhindwara District, Madhya Pradesh, India. The ascostroma is dimidiate and generally subcircular in shape with a wavy margin, sometimes oval, and may be semicircular (when broken). It is unusually larger than other known fossil ascocarps. There is no opening in the middle, but in the section, the middle part is occasionally ruptured, giving an ostiolate-like appearance. The hyphae of the specimens are characteristic, with 8–25 hyphae closely placed side by side to form radial and transverse strands, which are slightly twisted and rope-like. The strands are interconnected to form net-like structures. Cellular structures are often branched at the margins. Free hyphae were not observed, and the stroma was one-celled. The margin is generally set, and the cells are thicker with smaller meshes (Srivastava & Kar 2004). Only one species listed in Index Fungorum (2023) under this genus.

Type species: Polyhyphaethyrites giganticus R. Srivast. & R.K. Kar.


Figure 1  Polyhyphaethyrites giganticusScale bar = 500 μm. Redrawn from Srivastava & Kar (2004).


Srivastava R, Kar RK. 2004 – Record of new petrified epiphyllous fungi (Polyhyphaethyrites) from the Deccan Intertrappaen beds of Mohgaon Kalan, Madhya Pradesh, India. Current Science 87, 866–867.

Entry by

Ramesh K. SaxenaBirbal Sahni Institute of Palaeosciences, Lucknow, India

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