The hidden diversity of the fungal partners in the carton nest of Lasius fuliginosus (Hymenoptera: Formicidae)

 

Student/in: Katharina Russ, BSc
Termin: 10.02.2023 , 13:00 Uhr
Ort: Seminarraum Mikrobiologie

1. Prüfer/in: Martin Kirchmair, Mag. Dr. Priv.-Doz
2. Prüfer/in: Susanne Zeilinger-Migsich, Univ. Prof. Mag. Dr.
Vorsitzende/r: Andreas Wagner, Mag. Dr. Priv.-Doz

 

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Abstract

The present study examined the fungal core mycobiome of Lasius fuliginous carton nests. Three different nests were sampled in September and October 2021, the first two nests are located in Innsbruck, Tyrol in Picea abies and the third nest was from Konstanz, Baden-Württemberg in Acer platanoides. Trees were sampled using a drill to get to the nest carton material inside the tree. For the isolation of the fungi in the carton nest, the dilution to extinction method was used. This cultivation method allowed 355 pure cultures to be isolated, which were then further analysed with molecular biological methods and phylogenetic analyses using a Maximum Likelihood (ML) tree.

All the isolated fungi belonged to phylum Ascomycota. The most found order was Chaetothyriales (Eurotiomycetes), also known as black yeasts, containing the genera Cladophialophora, Exophiala, Phialophora and Cyphellophora. Also, fungi from the genus Ochroconis (Venturiales) were found. These two orders accounted for the most commonly isolated fungi, resulting in the core mycobiome of the fungal partners of the Lasius fuliginosus carton nests (Chaetothyriales 67.6 %, Venturiales 23.3 % of the total fungi). Fungi of the genera Lophiostoma and Nigrograna (Pleosporales), and Rhizodiscina (Aulographales) were present in low abundance. Phylogenetically, the majority of the Chaetothyriales isolates of the sampled nests clustered with or close to fungi of other carton nests. The Venturiales clustered in two different clades with fungal isolates of other Lasius fuliginosus carton nests. For the first time there is a clear insight in the fungal core mycobiome of Lasius fuliginosus carton nests. Carton nests of this ants are a high diversity habitat, resulting in as of yet undescribed fungal species. Further studies may look deeper in this mutualism and also include the bacterial community.