A phylogenetically-based nomenclature for Cordycipitaceae (Hypocreales)

Abstract

The ending of dual nomenclatural systems for pleomorphic fungi in 2011 requires the reconciliation of competing names, ideally linked through culture based or molecular methods. The phylogenetic systematics of Hypocreales and its many genera have received extensive study in the last two decades, however resolution of competing names in Cordycipitaceae has not yet been addressed. Here we present a molecular phylogenetic investigation of Cordycipitaceae that enables identification of competing names in this family, and provides the basis upon which these names can be maintained or suppressed. The taxonomy presented here seeks to harmonize competing names by principles of priority, recognition of monophyletic groups, and the practical usage of affected taxa. In total, we propose maintaining nine generic names, Akanthomyces, Ascopolyporus, Beauveria, Cordyceps, Engyodontium, Gibellula, Hyperdermium, Parengyodontium, and Simplicillium and the rejection of eight generic names, Evlachovaea, Granulomanus, Isaria, Lecanicillium, Microhilum, Phytocordyceps, Synsterigmatocystis, and Torrubiella. Two new generic names, Hevansia and Blackwellomyces, and a new species, Beauveria blattidicola, are described. New combinations are also proposed in the genera Akanthomyces, Beauveria, Blackwellomyces, and Hevansia.

Keywords: Akanthomyces; Ascopolyporus; Beauveria; Blackwellomyces; Cordyceps; Dual nomenclature; Engyodontium; Gibellula; Hevansia; Hyperdermium; Parengyodontium; Simplicillium.

Fig. 1.

RAxML tree of Cordycipitaceae. Dataset included 392 taxa and a concatenated alignment of 4569 bp from five nuclear genes (SSU, LSU, TEF, RPB1, and RPB2). Tips in bold represent examples of type species for their associated genera. Proposed genus level names to protect are delimited, but names of individual species have not been changed on the leaves of the tree, demonstrating diversity of taxa sampled. Values above branches are bootstrap proportions.

Fig. 2.

Beauveria blattidicola (MCA1727 – holotype). A. Fresh stroma on cockroach. B. Dried stroma on cockroach. C. Stroma with partially immersed perithecia. D. Perithecia. E. Ascus showing prominent ascus cap. F. Ascus showing cylindrical ascospores. G. Part-spores. H. End of ascus showing ascus foot. Bars: A–B = 4 mm; C= 150 μm; D = 50 μm; E–H = 5 μm.

Fig. 3.

Representative taxa for Cordycipitaceae. A. Isaria sp. CEM 1729). B. Torrubiella arachnophila (rmk 12-001). C. Cordyceps bifusispora (CEM 1615). D. Cordyceps confragosa (CEM 1633). E. Isaria tenuipes (CEM 1032). F.Cordyceps militaris (CEM 740). G. Cordyceps rosea (CEM 1734). H. Cordyceps cf. cardinalis (CEM 1733). I. Cordyceps takaomontana with co-occurring I. tenuipes (CEM 1954). J. Cordyceps nelumboides (TNS 16306). Images not to scale.