A revision of Verticillium section Prostrata. IV. The genera Lecanicillium and Simplicillium gen. nov.
Zare, R.; Gams, W.
A major part of the species formerly classified in Verticillium sect. Prostrata is transferred to Lecanicillium. Fifteen species are named in Lecanicillium (of which three are new species), and two, of which insufficient material is available, are informally treated. Taxa with conidial chains are not included. Four taxa with mainly solitary phialides, which form a distinct clade outside that of Lecanicillium, are classified in the new genus Simplicillium with the necessary new combinations. Simplicillium wallacei is introduced as a new species close to S. lamellicola, together with its new teleomorph, Torrubiella wallacei. Among numerous isolates originally identified as V. lecanii, ten, mainly tropical isolates are considered to represent this species, 24 belong to L. muscarium, five to L. longisporum, and four to L. nodulosum. 11 isolates are reclassified as Simplicillium lanosoniveum. The concept of the former Verticillium psalliotae is also restricted, for which nine isolates are representative. Chlamydospore-producing parasites of rust fungi identified under this species or as Verticillium epiphytum are only distantly related to Lecanicillium and cannot yet be satisfactorily classified. Aphanocladium aranearum, with its rapidly collapsing aphanophialides, is closely related to L. psalliotae and is included in this genus as L. aphanocladii nom. nov. In contrast, the type species of Aphanocladium, A. album, is quite unrelated. Lecanicillium dimorphum, having both kinds of conidiogenesis, links L. psalliotae with L. aphanocladii. Engyodontium aranearum forms another member of this complex. Because it is quite distinct from the type species of the genus, it is reclassified in Lecanicillium under the new name L. tenuipes. A single isolate is available that matches L. aranearum, while the similar new species L. evansii is be based on five isolates. Two other new species are L. attenuatum and L. acerosum. A neotype is designated for L. psalliotae, epitypes are designated for L. muscarium, L. nodulosum, and L. aphanocladii.