Fungalpedia – Note 193Dyadosporites (Fossil Fungi)


Dyadosporites Clarke

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

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

Classification: Didymosporae, Fossil Fungi.

Clarke (1965) described the monotypic fossil genus, Dyadosporites, from Late Cretaceous (100–66 mya) sediments in the Canon City Coalfield, Fremont County, Colorado, U.S.A. According to the original diagnosis, this genus includes bilocular (didymosporous) elliptical spores having a simple central septum, psilate to finely punctate spore wall, and a single pore at the apex of each cell. Kalgutkar & Jansonius (2000emended the generic diagnosis to include dicellate fungal spores of various shapes and having psilate to variously sculptured spore walls.

The generic name Dyadosporites first appeared in van der Hammen (1954) with D. umeriensis as its type. The diagnosis for D. umeriensis has never been published; therefore, the genus publication was not considered valid. Clarke (1965, p. 90) considered Dyadosporites as validly published and described under it as a single species, D. ellipsus. Clarke (1965) also provided a restated diagnosis for Dyadosporites. Therefore, Dyadosporites is considered valid, and it was published by Clarke (1965) using the principle of monotypy. Elsik (1968) did not consider Dyadosporites as validly published and proposed another genus, Dyadosporonites, with the following diagnosis: “Diporate, uniseptate fungal spores. Shape and ornamentation variable. Single pore at each end of the spore. Pore may be modified, i.e., atrium, annulus or pore chamber formed by a thin septum across the end of spore.” Since Dyadosporites and Dyadosporonites entirely overlap, the latter is considered the latter synonym of the former. Kalgutkar & Jansonius (2000) considered Psidimobipiospora Sal. -Cheb. & Locq. 1980 is also the later synonym of Dyadosporonites.

Synonyms: Dyadosporites HammenDyadosporonites Elsik. Psidimobipiospora Sal. -Cheb. & Locq.

Type species: Dyadosporites ellipsus Clarke (by monotypy).

Other accepted species: (Species Fungorum – search Dyadosporites)



Figure 1 – Dyadosporites ellipsusScale bar = 10 μm. Redrawn from Clarke (1965)



Clarke RT. 1965 – Fungal spores from Vermejo Formation coal beds (Upper Cretaceous) of Central Colorado. Mountain Geologist 2, 85–93. 

Elsik WC. 1968 – Palynology of a Palaeocene Rockdale lignite, Milam County, Texas. 1. Morphology and taxonomy. Pollen et Spores 10(2), 263–314. 

Kalgutkar RM, Jansonius J. 2000 – Synopsis of fungal spores, mycelia and fructifications. AASP Contribution Series 39, 1–423. 

Salard-Cheboldaeff M, Locquin MV. 1980 – Champignons présents au Tertiaire le long du littoral de l’Afrique équatoriale. 105e Congrès National des Sociétés savantes, Caen, Sciences, fascicule 1, 183–195

Van der Hammen T. 1954 – Principios para la nomenclatura palinologica sistemetica. Boletin Geologico (Bogota) 2(2), 3–24.



Entry by

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


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