Abstract Detail

Mycology

Haelewaters, Danny [1], de Groot, Michiel D [2], Hiller, Thomas [3], Nedvěd, Oldřich [4], Aime, M. Catherine [5].

What parasites like: abiotic factors influencing the occurrence of Laboulbeniales fungi.

Laboulbeniales (Ascomycota, Laboulbeniomycetes) are an order of fungi obligatorily associated with arthropod hosts, often with strict host specificity. Despite it being a diverse group with up to 75,000 estimated species, their classification is unresolved, parasite-host interactions are largely unexplored, and thus far no community ecology studies have been done. Here, we examined how abiotic traits affect the prevalence of Laboulbeniales in two study systems: Hesperomyces harmoniae nom. prov. on the globally invasive ladybird Harmonia axyridis (Coleoptera, Coccinellidae); and Arthrorhynchus, Gloeandromyces, and Nycteromyces spp. on bat-parasitic bat flies (Diptera, Nycteribiidae and Streblidae). We screened over 3,500 Ha. axyridis ladybirds in Central Europe and tested the effects of climate and landscape variables on parasite prevalence. Mean prevalence was 18%, ranging among samples from 0% to 46%. Parasite prevalence was negatively affected by low temperatures and precipitation, whereas higher temperatures in the warmest month resulted in significant higher prevalence. We found a significant positive effect of the amount of agricultural land surrounding collection sites on parasite prevalence. Abiotic effects were only significant for buffer radii of 300m to either 600m or 1km, indicating that local-scale climatic traits determine infection patterns of Ha. axyridis by He. harmoniae. For the second study system, we constructed a database of currently 12,300 bat flies from the Americas and Europe, and analyzed how humidity, temperature, and bat roosting behavior contribute to prevalence. Mean prevalence was 3.8% (2.8% on nycteribiids, 4.0% on streblids). Temperature and humidity affected prevalence significantly, but effects were different between the Neotropical and European species, likely indicating the importance of local scale data. Bat roosting also had a significant effect on infection rates; roost permanence, as classified from ephemeral (leaf tents) to permanent (caves and tunnels), was positively correlated to Laboulbeniales infection. Bats also have higher levels of bat fly parasitism in more permanent roosts, and our results imply that the Laboulbeniales follow suit in this more stable environment. With our work, equipped with molecular tools and techniques, following standardized data collection, and by investing in international collaborations, we hope to shed more light on this group of fungal parasites. Being both microfungi and parasites-two organismal groups that are severely understudied-Laboulbeniales continue to offer great potential as models for studying basic evolutionary and ecological questions.

1 - Ghent University, Department of Biology, Research Group Mycology, K.L. Ledeganckstraat 35, Ghent, 9000, Belgium
2 - Naturalis Biodiversity Center, Research Group Evolutionary Ecology, Darwinweg 2, Leiden, 2333 CR, The Netherlands
3 - University of Hohenheim, Department of Ecology of Tropical Agricultural Systems, Garbenstrasse 13, Stuttgart, 70599, Germany
4 - University of South Bohemia, Faculty of Science, Branišovská 31, České Budějovice, 370 05, Czech Republic
5 - Purdue University, Department of Botany and Plant Pathology, 915 W. State Street, West Lafayette, IN, 47907, USA

Keywords:
climatic variables
parasite prevalence
agricultural land
community ecology
Laboulbeniomycetes
hyperparasites
Mycology.

Presentation Type: Oral Paper
Session: MY2, Mycology: Human and Animal Pathogens
Location: /
Date: Tuesday, July 20th, 2021
Time: 12:30 PM(EDT)
Number: MY2001
Abstract ID:312
Candidate for Awards:MSA Best Oral Presentation Award by a Graduate Student