Abstract Fungus‐farming ants (Hymenoptera: Formicidae) have become model systems for exploring questions regarding the evolution of symbiosis. However, robust phylogenetic studies of both the ant agriculturalists and their fungal cultivars are necessary for addressing whether or not observed ant–fungus associations are the result of coevolution and, if so, whether that coevolution has been strict or diffuse. Here we focus on the evolutionary relationships of the species within the ant genusMyrmicocryptaand of their fungal cultivars. The fungus‐farming ant genusMyrmicocryptawas created by Fr. Smith in 1860 based on a single alate queen. Since then, 31 species and subspecies have been described. Until now, the genus has not received any taxonomic treatment and the relationships of the species within the genus have not been tested. Our molecular analyses, using ∼40 putative species and six protein‐coding (nuclear and mitochondrial) gene fragments, recoverMyrmicocryptaas monophyletic and as the sister group of the genusMycocepurusForel. The speciesM. tuberculataWeber is recovered as the sister to the rest ofMyrmicocrypta. The time‐calibrated phylogeny recovers the age of stem groupMyrmicocryptaplus its sister group as 45 Ma, whereas the inferred age for the crown groupMyrmicocryptais recovered as 27 Ma. Ancestral character‐state analyses suggest that the ancestor ofMyrmicocryptahad scale‐like or squamate hairs and that, although such hairs were once considered diagnostic for the genus, the alternative state of erect simple hairs has evolved at least seven independent times. Ancestral‐state analyses of observed fungal cultivar associations suggest that the most recent common ancestor ofMyrmicocryptacultivated clade 2 fungal species and that switches to clade 1 fungi have occurred at least five times. It is our hope that these results will encourage additional species‐level phylogenies of fungus‐farming ants and their fungal cultivars, which are necessary for understanding the evolutionary processes that gave rise to agriculture in ants and that produced the current diversity of mutualistic ant–fungus interactions.
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Masters of the manipulator: two new hypocrealean genera, Niveomyces ( Cordycipitaceae ) and Torrubiellomyces ( Ophiocordycipitaceae ), parasitic on the zombie ant fungus Ophiocordyceps camponoti-floridani
During surveys in central Florida of the zombie-ant fungus Ophiocordyceps camponoti-floridani , which manipulates the behavior of the carpenter ant Camponotus floridanus , two distinct fungal morphotypes were discovered associated with and purportedly parasitic on O. camponoti-floridani . Based on a combination of unique morphology, ecology and phylogenetic placement, we discovered that these morphotypes comprise two novel lineages of fungi. Here, we propose two new genera, Niveomyces and Torrubiellomyces , each including a single species within the families Cordycipitaceae and Ophiocordycipitaceae , respectively. We generated de novo draft genomes for both new species and performed morphological and multi-loci phylogenetic analyses. The macro-morphology and incidence of both new species, Niveomyces coronatus and Torrubiellomyces zombiae , suggest that these fungi are mycoparasites since their growth is observed exclusively on O. camponoti-floridani mycelium, stalks and ascomata, causing evident degradation of their fungal hosts. This work provides a starting point for more studies into fungal interactions between mycopathogens and entomopathogens, which have the potential to contribute towards efforts to battle the global rise of plant and animal mycoses.
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- Award ID(s):
- 1941546
- PAR ID:
- 10422875
- Date Published:
- Journal Name:
- Persoonia - Molecular Phylogeny and Evolution of Fungi
- Volume:
- 49
- Issue:
- 1
- ISSN:
- 0031-5850
- Page Range / eLocation ID:
- 171 to 194
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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