Skip to main content
ARS Home » Northeast Area » Ithaca, New York » Robert W. Holley Center for Agriculture & Health » Emerging Pests and Pathogens Research » Research » Publications at this Location » Publication #304917

Title: Clavicipitaceous entomopathogens: New species of Metarhizium and a new genus Nigelia

item LUANGSA-ARD, J. JENNIFER - Biotec-Nstda
item KHONSANIT, ARTIT - Biotec-Nstda
item TASANATHAI, KANOKSRI - Biotec-Nstda
item NOISRIPOOM, WASANA - Biotec-Nstda
item Humber, Richard

Submitted to: Mycological Progress
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/31/2017
Publication Date: 2/23/2017
Citation: Luangsa-Ard, J., Mongkolsamrit, S., Thanakitpipattana, D., Khonsanit, A., Tasanathai, K., Noisripoom, W., Humber, R.A. 2017. Clavicipitaceous entomopathogens: New species of Metarhizium and a new genus Nigelia. Mycological Progress. 16(4):369-391.

Interpretive Summary: This manuscript reports the results of the taxonomic evaluations of fungal pathogens affecting insects over several years of collecting in Thailand. The sexual and conidial stages of the ascomycete fungi discussed here are all referable to the family Clavicipitaceae (order Hypocreales). The results reported here expand and refine the concepts of some genera that are now undergoing major reclassifications based on both phylogenetic analyses of their genomes and in accordance with new rules of nomenclature. A new genus is described as being closely related to but distinct from Metarhizium, and several taxa that have not been reclassified under the newly (phylogenetically) revised classifications are assigned into their appropriate genera. Such studies advance the knowledge of fungal biodiversity and help to clarify the concepts of a number of important fungal genera. These studies help to guide future studies of these fungi as possible biological control agents that might be used against agriculturally important pests.

Technical Abstract: In several surveys in the tropical forests in Thailand, specimens that looked morphologically similar to Metarhizium martialis and Cordyceps variegata, as well as Metarhizium species were collected and cultured in vitro. A combined phylogeny of several genes including the small (18S) and large (28S) subunits of the ribosomal DNA, elongation factor 1-alpha (TEF), RNA polymerase II subunits 1 and 2 (RPB1, RPB2) genes has shown these to be new taxa in the Clavicipitaceae. Caperrocordyceps is described as a new genus closely related to Metarhizium, to the scale insect pathogens Aschersonia (Hypocrella), Samuelsia and Moelleriella, and to plant pathogens in Claviceps and Balansia, and other relatives. Caperrocordyceps aurantiaca is a pathogenic fungus infecting lepidopteran larvae that produces pseudoimmersed, obliquely arranged, obpyriform perithecia with curved or bent ostioles and with whole (non-separating) cylindric ascospores. Metarhizium samlanensis, Met. blattae, Met. prachinensis, and Met. kalasinensis are described as new species of Metarhizium. Metarhizium martialis is transferred into Caperrocordyceps, and Paecilomyces reniformis is transferred into Metarhizium.