Architrypethelium murisporum (Ascomycota, Trypetheliaceae), a remarkable new lichen species from Thailand challenging ascospore septation as an indicator of phylogenetic relationships.

Theerapat Luangsuphabool,Jittra Piapukiew,Ek Sangvichien,H Thorsten Lumbsch

doi:10.3897/mycokeys.25.23836

Theerapat Luangsuphabool, Jittra Piapukiew + Show 2 more

Open Access

https://doi.org/10.3897/mycokeys.25.23836

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Abstract

Architrypethelium murisporum Luangsuphabool, Lumbsch & Sangvichien is described for a crustose lichen occurring in dry evergreen forest in Thailand. It is characterised by a green to yellow-green corticated thallus, perithecia fused in black pseudostromata with white rim surrounding the ostiole and small, hyaline and muriform ascospores. Currently, all species in the genus Architrypethelium have transversely septate ascospores, hence the discovery of this new species indicates that ascospore septation is variable within the genus, similar to numerous other groups of lichen-forming ascomycetes. Phylogenetic analyses of two loci (mtSSU and nuLSU) supported the position of the new species within Architrypethelium. This is the first report of the genus in Southeast Asia.

Highlights

The genus Architrypethelium Aptroot (Ascomycota, Dothideomycetes, Trypetheliales) includes crustose lichens with perithecioid ascomata growing on tree bark in the tropics (Aptroot 1991, Aptroot et al 2008, Aptroot and Lücking 2016)
The tree topology supported the fact that the new species is part of the genus Architrypethelium with strong support values (Fig. 1)
The morphological characters of the new species would place it in the genus Astrothelium (Fig. 2), the shape of ascospore lumina is somewhat different from Astrothelium in having rounded-shaped lumina (Fig. 2C) (Aptroot and Lücking 2016)

Summary

Introduction

The genus Architrypethelium Aptroot (Ascomycota, Dothideomycetes, Trypetheliales) includes crustose lichens with perithecioid ascomata growing on tree bark in the tropics (Aptroot 1991, Aptroot et al 2008, Aptroot and Lücking 2016). The genus accommodates species with a corticate thallus, solitary or aggregate ascomata with apical or eccentric ostioles, a clear or inspersed hymenium and hyaline or brown, 3–5 septate, transversely septate ascospores (Aptroot et al 2008, Aptroot and Lücking 2016). While most genera in Trypetheliaceae, such as Astrothelium s.str., Bathelium, Polymeridium and Viridothelium include species with various ascospore types (Hyde et al 2013, Nelsen et al 2014, Aptroot and Lücking 2016, Lücking et al 2016b), the species of Architrypethelium shared a similar ascospore morphology (Nelsen et al 2014, Lücking et al 2016b).

Results

Conclusion