Paracapsulospora Konta. & K. D. Hyde, gen. nov.

Saprobic on dead Metroxylon sagu (Arecaceae). Sexual morph Ascomata solitary, immersed, uniloculate, globose to subglobose, surrounded by a dark brown layer of peridium cells. Peridium composed of outer layers of black, thick-walled cells of textura angularis inner layers hyaline and thin-walled. Asci 8-spored, unitunicate, cylindrical, long pedicellate. Ascospores uni-seriate, oblong to cylindrical, unicellular, hyaline, with two guttules, thin-walled, smoothwalled, have appendages with a distinct mucilaginous sheath. Asexual morph Undetermined.

Note: Paracapsulospora is introduced to accommodate a single species P. metroxyli which was collected from Metroxylon in Thailand. The genus is morphologically similar to Capsulospora and Xylochrysis in having cylindrical asci with uni-seriate and oblong to cylindrical, aseptate ascospores. Paracapsulospora is most similar to Capsulospora in having immersed ascomata, with uni-seriate, hyaline, oblong to cylindrical, aseptate ascospores. Paracapsulospora differs from Xylochrysis in forming immersed ascomata, with hyaline ascospores, while Xylochrysis forms ascostromata erumpent through host tissue by long neck and forms paraphyses, with pale brown ascospores However, these two genera can be distinguished as Paracapsulospora has appendages at both ends of ascospores and does not produce paraphyses at the centrum, whereas Capsulospora forms paraphyses buts lacks appendages. Phylogenetic analyses show that Paracapsulospora is close to the orders Magnaporthales and Amplistromatales but cannot be confidently assigned to these order due to weak support. Based on the limited sequences data in this group, we could not clarify the natural placement of our genus. Thus, we treat the new genus in the Sordariomycetes genera incertae sedis.

Type species: Paracapsulospora metroxyli Konta. & K.D. Hyde

Fig.  Maximum likelihood phylogenetic tree generated by RAxML (GTR+G model) based on LSU sequence data. ML/MP values (

[50 %) resulting from 1000 bootstrap replicates are given at the nodes and branches with Bayesian posterior probabilities greater than 0.90 are in bold. The original isolate or specimen numbers are noted after the species names. The tree is rooted to Colletotrichum asianum. Newly generated sequence is in red and other ex-type
strains are in bold.


    • Paracapsulospora metroxyli