Fungalpedia – Note 142 Morellospora


Morellospora D. Corsaro, J. Walochnik, D. Venditti, B. Hauröder, R. Michel 

Citation when using this entry: Shah et al. (in prep) – Fungalpedia, new genera in 2020. Mycosphere 

            Incertae sedis, Incertae sedis, Incertae sedis, Rozellidea, Paramycia, Choanozoa

Index FungorumFacesoffungiMycoBankGenBank, Fig 1.

            The monotypic genus Morellospora was introduced by Corsaro et al. (2020) with an uncertain position in Microsporidia, Protozoa. The strain was isolated from an amoebae, Saccamoeba sp. found in the bark of a plane tree at Sayn near Bendorf, Mayen-Koblenz District, Western Germany (Corsaro et al. 2020)


Figure 1 – Morphological characteristics of Morellospora saccamoebae (intracytoplasmic parasite) (redrawn from Corsaro et al. 2020). a Cyst with spine-like structure. b Parasitosphorous vacuoles bearing spores without flagella, microsporidial structure with polar filament, curves polar sacs and anchor disks. Freely moving uninuclear sporonts. c Binucleate sporont in the host cytoplasm. d Two uninuclear sporonts with a distinct nucleus. Scale bars: a – b = 1 μm, c = 0.5 μm,  d = 0.2 μm


It is characterized by a distinct polar filament-like structure with a curved polar sac and a double membranous rounded mitochondria-like structure and sporonts (vesicular nucleus). Each vacuole contains a cluster of 10 mature spores that appeared as blackberries. Phylogenetic analysis based on ITS and LSU showed no close phylogenetic relationships between Morellospora and Microsporidia (Corsaro et al. 2020).

            Type species: Morellospora  saccamoebae D. Corsaro, J. Walochnik, D. Venditti, B. Hauröder, R. Michel 



Corsaro D, Walochnik J, Venditti D, Hauröder B et al. 2020 – Solving an old enigma:       Morellospora saccamoebae gen. nov., sp. nov. (Rozellomycota), a Sphaerita-like  parasite of free-living amoebae. Parasitology Research 119, 925934.


Entry by

Sujit Shah, Center of Excellence in Fungal Research, Mae Fah Luang University, Chiang Rai 57100, Thailand.


Edited by Antonio R. Gomes de Farias & Kevin D. Hyde