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1.
Persoonia ; 49: 171-194, 2022 Dec 20.
Artículo en Inglés | MEDLINE | ID: mdl-38234384

RESUMEN

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 macromorphology 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. Citation: Araújo JPM, Lebert BM, Vermeulen S, et al. 2022. Masters of the manipulator: two new hypocrealean general, Niveomyces (Cordycipitaceae) and Torrubiellomyces (Ophiocordycipitaceae), parasitic on the zombie ant fungus Ophiocordyceps camponoti-floridani. Persoonia 49: 171-194. https://doi.org/10.3767/persoonia.2022.49.05.

2.
Stud Mycol ; 90: 119-160, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29910522

RESUMEN

Ophiocordyceps species infecting ants - the so-called zombie-ant fungi - comprise one of the most intriguing and fascinating relationships between microbes and animals. They are widespread within tropical forests worldwide, with relatively few reports from temperate ecosystems. These pathogens possess the ability to manipulate host behaviour in order to increase their own fitness. Depending on the fungal species involved the infected ants are manipulated either to leave the nest to ascend understorey shrubs, to die biting onto vegetation, or descend from the canopy to die at the base of trees. Experimental evidence has demonstrated that the behavioural change aids spore dispersal and thus increases the chances of infection, because of the existing behavioural immunity expressed inside ant colonies that limits fungal development and transmission. Despite their undoubted importance for ecosystem functioning, these fungal pathogens are still poorly documented, especially regarding their diversity, ecology and evolutionary relationships. Here, we describe 15 new species of Ophiocordyceps with hirsutella-like asexual morphs that exclusively infect ants. These form a monophyletic group that we identified in this study as myrmecophilous hirsutelloid species. We also propose new combinations for species previously described as varieties and provide for the first time important morphological and ecological information. The species proposed herein were collected in Brazil, Colombia, USA, Australia and Japan. All species could readily be separated using classic taxonomic criteria, in particular ascospore and asexual morphology.

3.
Mycologia ; 112(6): 1138-1170, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33146584

RESUMEN

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.


Asunto(s)
Hormigas/microbiología , Interacciones Huésped-Patógeno , Hypocreales/clasificación , Hypocreales/genética , Animales , Brasil , Ghana , Hypocreales/aislamiento & purificación , Masculino , Filogenia , Bosque Lluvioso , Especificidad de la Especie , Esporas Fúngicas
4.
Fungal Syst Evol ; 1: 13-22, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32518897

RESUMEN

The type of Ophiocordyceps unilateralis (Ophiocordycipitaceae, Hypocreales, Ascomycota) is based on an immature specimen collected on an ant in Brazil. The host was identified initially as a leaf-cutting ant (Atta cephalotes, Attini, Myrmicinae). However, a critical examination of the original illustration reveals that the host is the golden carpenter ant, Camponotus sericeiventris (Camponotini, Formicinae). Because the holotype is no longer extant and the original diagnosis lacks critical taxonomic information - specifically, on ascus and ascospore morphology - a new type from Minas Gerais State of south-east Brazil is designated herein. A re-description of the fungus is provided and a new phylogenetic tree of the O. unilateralis clade is presented. It is predicted that many more species of zombie-ant fungi remain to be delimited within the O. unilateralis complex worldwide, on ants of the tribe Camponotini.

5.
Adv Genet ; 94: 437-69, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27131331

RESUMEN

Parasites can manipulate the behavior of their hosts in ways that increase either their direct fitness or transmission to new hosts. The Kingdom Fungi have evolved a diverse array of strategies to manipulate arthropod behavior resulting in some of the most complex and impressive examples of behavioral manipulation by parasites. Here we provide an overview of these different interactions and discuss them from an evolutionary perspective. We discuss parasite manipulation within the context of Niko Tinbergen's four questions (function, phylogeny, causation, and ontogeny) before detailing the proximate mechanisms by which fungi control arthropod behavior and the evolutionary pathways to such adaptations. We focus on some systems for which we have recently acquired new knowledge (such as the zombie ant fungus, Ophiocordyceps unilateralis s.l.), but a major goal is also to highlight how many interesting examples remain to be discovered and investigated. With this in mind, we also discuss likely examples of manipulated spiders that are largely unexplored ("zombie spiders"). Armed with advanced tools in evolutionary biology (from serial block face SEM to RNAseq) we can discover how the fungi, a group of microbes capable of coordinated activity, have evolved the ability to direct animal behavior. In short, we have the ability to understand how the organism without the brain controls the one with the brain. We hope such a goal, coupled with the knowledge that many diverse examples of control exist, will inspire other organismal biologists to study the complex adaptations that have arisen from "so simple a beginning."


Asunto(s)
Conducta Animal , Hongos/patogenicidad , Interacciones Huésped-Patógeno/fisiología , Insectos/fisiología , Adaptación Biológica , Animales , Hormigas/microbiología , Hormigas/fisiología , Control de la Conducta , Biodiversidad , Hypocreales/patogenicidad , Hypocreales/fisiología , Insectos/microbiología , Filogenia
6.
Phys Rev Lett ; 101(11): 111301, 2008 Sep 12.
Artículo en Inglés | MEDLINE | ID: mdl-18851271

RESUMEN

The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 and theta=34.4_-1.2;+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results.

7.
Mycopathologia ; 141(1): 21-36, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-16284862

RESUMEN

A two-year survey of the fungi associated with two important congeneric pantropical weeds, Euphorbia heterophylla and E. hirta, was conducted in part of their native range in southern Brazil. Sampling was concentrated mainly in Rio de Janeiro State and ten species were identified as pathogens of these weeds. Two taxa, Botrytis ricini and Uromyces euphorbiae, were common to both weed hosts. Alternaria euphorbiicola, Bipolaris euphorbiae, Melampsora sp., Oidium sp. and Sphaceloma poinsettiae were recorded only from E. heterophylla, whereas Colletotrichum gloeosporioides, Sphaceloma sp. and Sphaerotheca fuliginea were restricted to E. hirta. Botrytis ricini and Colletotrichum gloeosporioides are new records for E. hirta, and Alternaria euphorbiicola and Sphaerotheca fuliginea are new host records for Brazil. Bipolaris euphorbiae, previously identified as Helminthosporium sp., is considered to be the correct name for the causal agent of a major disease of E. heterophyllum in Brazil. The potential of these pathogens as biocontrol agents is discussed and the mycobiota associated with both these weeds worldwide is reviewed.

8.
Mycopathologia ; 144(2): 81-5, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-16284837

RESUMEN

Pistia stratioites, the water lettuce, is an important pantropical aquatic weed. It has been the target of successful classical biocontrol programmes utilizing an insect natural enemy collected in Brazil and introduced into Australia, Papua New Guinea and South Africa. Little attention was given to the fungal pathogens associated with this weed as potential biocontrol agents. An 11-month field survey in the state of Rio de Janeiro involving repeated visits to 12 sites, and a 2-month survey in the Amazonas Basin (Amazonas state) in Brazil, yielded only one pathogenic fungus on P. stratioites. This was identified as Cercospora pistiae. No previous record of this species has been made in Brazil nor in the New World. The fungus is described and its taxonomy and biocontrol potential discussed herein. C. pistiae is a damaging pathogen of water lettuce. Its distribution was restricted to two interconnected sites in Rio de Janeiro. A literature and herbaria survey yielded few fungi associated to water lettuce (8 species), probably reflecting a lack of adequate collection in the centre of origin of the plant.

9.
Leg Med ; : 21-9, 1980.
Artículo en Inglés | MEDLINE | ID: mdl-7421389

RESUMEN

The initial protection of the homicide scene by the first investigators to arrive plays a vital part in allowing the accumulation of evidence that can lead to conviction. A given set of circumstances which comprises a given scene is never left wholly unchanged by the commission of a crime and/or the passage of the perpetrator to or from that scene.


Asunto(s)
Medicina Legal , Homicidio , Adulto , California , Femenino , Humanos
10.
Phys Rev Lett ; 92(10): 102004, 2004 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-15089201

RESUMEN

Data from the Sudbury Neutrino Observatory have been used to constrain the lifetime for nucleon decay to "invisible" modes, such as n-->3nu. The analysis was based on a search for gamma rays from the deexcitation of the residual nucleus that would result from the disappearance of either a proton or neutron from 16O. A limit of tau(inv)>2 x 10(29) yr is obtained at 90% confidence for either neutron- or proton-decay modes. This is about an order of magnitude more stringent than previous constraints on invisible proton-decay modes and 400 times more stringent than similar neutron modes.

11.
Phys Rev Lett ; 92(18): 181301, 2004 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-15169480

RESUMEN

The Sudbury Neutrino Observatory has precisely determined the total active (nu(x)) 8B solar neutrino flux without assumptions about the energy dependence of the nu(e) survival probability. The measurements were made with dissolved NaCl in heavy water to enhance the sensitivity and signature for neutral-current interactions. The flux is found to be 5.21 +/- 0.27(stat)+/-0.38(syst) x 10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of these and other solar and reactor neutrino results yields Deltam(2)=7.1(+1.2)(-0.6) x 10(-5) eV(2) and theta=32.5(+2.4)(-2.3) degrees. Maximal mixing is rejected at the equivalent of 5.4 standard deviations.

12.
Phys Rev Lett ; 87(7): 071301, 2001 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-11497878

RESUMEN

Solar neutrinos from (8)B decay have been detected at the Sudbury Neutrino Observatory via the charged current (CC) reaction on deuterium and the elastic scattering (ES) of electrons. The flux of nu(e)'s is measured by the CC reaction rate to be straight phi(CC)(nu(e)) = 1.75 +/- 0.07(stat)(+0.12)(-0.11)(syst) +/- 0.05(theor) x 10(6) cm(-2) s(-1). Comparison of straight phi(CC)(nu(e)) to the Super-Kamiokande Collaboration's precision value of the flux inferred from the ES reaction yields a 3.3 sigma difference, assuming the systematic uncertainties are normally distributed, providing evidence of an active non- nu(e) component in the solar flux. The total flux of active 8B neutrinos is determined to be 5.44+/-0.99 x 10(6) cm(-2) s(-1).

13.
Phys Rev Lett ; 89(1): 011301, 2002 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-12097025

RESUMEN

Observations of neutral-current nu interactions on deuterium in the Sudbury Neutrino Observatory are reported. Using the neutral current (NC), elastic scattering, and charged current reactions and assuming the standard 8B shape, the nu(e) component of the 8B solar flux is phis(e) = 1.76(+0.05)(-0.05)(stat)(+0.09)(-0.09)(syst) x 10(6) cm(-2) s(-1) for a kinetic energy threshold of 5 MeV. The non-nu(e) component is phi(mu)(tau) = 3.41(+0.45)(-0.45)(stat)(+0.48)(-0.45)(syst) x 10(6) cm(-2) s(-1), 5.3sigma greater than zero, providing strong evidence for solar nu(e) flavor transformation. The total flux measured with the NC reaction is phi(NC) = 5.09(+0.44)(-0.43)(stat)(+0.46)(-0.43)(syst) x 10(6) cm(-2) s(-1), consistent with solar models.

14.
Phys Rev Lett ; 89(1): 011302, 2002 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-12097026

RESUMEN

The Sudbury Neutrino Observatory (SNO) has measured day and night solar neutrino energy spectra and rates. For charged current events, assuming an undistorted 8B spectrum, the night minus day rate is 14.0%+/-6.3%(+1.5%)(-1.4%) of the average rate. If the total flux of active neutrinos is additionally constrained to have no asymmetry, the nu(e) asymmetry is found to be 7.0%+/-4.9%(+1.3%)(-1.2%). A global solar neutrino analysis in terms of matter-enhanced oscillations of two active flavors strongly favors the large mixing angle solution.

15.
Nature ; 232(5309): 346-7, 1971 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-5094846
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