Zombie-ant fungi cross continents: II. Myrmecophilous hymenostilboid species and a novel zombie lineage

ABSTRACT

Ophiocordyceps species infecting ants are globally distributed, with diversity concentrated in the tropics and decreasing with increasing latitude. Among these myrmecophilous species, the ones exhibiting the ability to manipulate host behavior, the so-called “zombie-ant fungi” of the O. unilateralis clade, have been studied progressively over the last decade. However, we know very little about other myrmecophilous groups, such as species within the Ophiocordyceps subgenus Neocordyceps. Species within this group exhibit Hymenostilbe asexual morphs with the ascospores readily breaking into part-spores and regularly kill their hosts on the forest floor, with few records of behavioral manipulation. Here, we describe five new species of Ophiocordyceps belonging to the subgenus Neocordyceps infecting ants in the rainforests of the Brazilian Amazon and Ghana and analyze their ability to manipulate host behavior. We also propose a new status for a species previously described as a variety, providing its phylogenetic placement for the first time. The species proposed herein can readily be separated using classic taxonomic criteria, and this is further supported by ecological and molecular multiloci data.

KEYWORDS:

• Ants
• behavior manipulation
• cryptic species
• Hymenostilbe
• multigene phylogeny
• Neocordyceps
• zombie-ant fungi
• 6 new taxa

ACKNOWLEDGMENTS

The authors would like to thank the reviewers for the valuable contributions, INPA staff in Brazil, especially to Maria Aparecida de Jesus, Rubenildo Lima, Mike Hopkins, Márcio Oliveira, and José Albertino Rafael. In Ghana, this work could not be possible without the support from CRIG (Cocoa Research Institute of Ghana). J.P.M.A. would like to highlight that despite the attempts of the Brazilian government to destroy national science by drastically cutting research funds, this work was possible through international collaborations.