Fungalpedia – Note 231, Diporipollis (Fossil Fungi)
Diporipollis S.K. Dutta & S.C.D. Sah emend. Kalgutkar & Janson.
Citation when using this entry: Saxena RK & Hyde KD. 2024 (in prep) – Fungalpedia, Fossil Fungi.
Index Fungorum, Facesoffungi, MycoBank, GenBank, Fig. 1
Classification: Phragmosporae, Fungi Imperfecti, Fossil Fungi
The monotypic fossil genus Diporipollis was described by Dutta & Sah (1970) from the Cherra Formation (Early Eocene, 56–48 mya) of Umstew, South Shillong Plateau, Meghalaya, India. According to the original generic diagnosis, this fungus is small to medium-sized and diporate with more or less globular to sub-spheroidal amb. Pores are placed one over the other, circular in shape, and encircled by one or more thickened rims. Exine is thin with psilate to scabrate or finely granulate surface sculpture. Kalgutkar & Jansonius (2000) emended the generic diagnosis: “Small to medium-sized, tri- to tetracellate conidia, of which the distal cell is much larger than the other cells. Although the basic structure can be compared to that of Brachysporisporites, here the distal cell is so inflated that it is spherical, or its width even larger than its length, commonly causing the spores to be (proximo-distally) compressed in the equatorial plane. This, in turn, causes the two or three proximal-most cells to collapse into each other. The spore wall is thin to very thin and prone to concentric folding in the distal cell; the septa is thin, with distinct rimmed pores, anchored by thick, opaque septal bases that, in proximo-distal compression, form concentric rings. When the compression is somewhat oblique, the proximal cells show that they are forming a short, more or less tapering tube, the end of which has a small, invisible pore, indicating that it is functionally a hilum.”
Although, Dutta & Sah (1970) proposed Diporipollis as a pollen genus, they compared it with fungal spore genera. Diporisporites Hammen and Diporites Hammen. They also differentiated this genus from pollen genera, viz. Banksieaeidites Cookson and Graminidites Cookson. Kalgutkar & Jansonius (2000, p. 90) considered it as ‘Fungi Imperfecti, Phragmosporae’.
Type species: Diporipollis assamicus S.K. Dutta & S.C.D. Sah
Figure 1 – Diporipollis assamicus. Scale bar = 10 μm. Redrawn from Dutta & Sah (1970).
References
Dutta SK, Sah SCD. 1970 – Palyno-stratigraphy of the Tertiary sedimentary formations of Assam: 5. Stratigraphy and palynology of south Shillong Plateau. Palaeontographica Abt. B 131, 1–72.
Entry by
Ramesh K. Saxena, Birbal Sahni Institute of Palaeosciences, Lucknow, India
(Edited by Samaneh Chaharmiri-Dokhaharani & Achala R. Rathnayaka)