Parametarhizium hingganense S. Gao, W. Meng, Li Xiang Zhang, Q. Yue, L. J. Xu, sp. nov.

Index Fungorum number: MB837523; Facesoffungi number: FoF

Etymology: referring to the location where the type material was collected.

Description: Colonies on PDA reaching 17–18 mm in 2 weeks, yellow, radially sulcate, velvety, with undulate margin; exudate lemon yellow; reverse yellow, radially sulcate. Colonies on SDAY reaching 17–20 mm, pale yellow, wrinkled, velvety, with undulate margin; reverse brown, wrinkled. Colonies on MEA reaching 15–18 mm, lemon yellow, radially sulcate, velvety; reverse brown, radially sulcate. Colonies on OA reaching 18–19 mm, flat, initially cream, turning lemon yellow due to the production of conidial masses; reverse pale yellow. Hyphae hyaline, septate, smooth-walled, 0.8–2.5 µm wide. Conidiophores arising from branches of aerial hyphae, bearing dense whorls of branches, terminating in branches with 2–4 phialides per branch, candelabrum-like arrangement of phialides. Phialides obpyriform (3.5–) 7.0–17.5 (–26)   ×  (1.2–) 1.4–2.3 (–2.5) µm, with a long distinct neck, (1.6–) 2.5–7.1 (–8.5)  ×  (0.5–) 0.6–1.1 (–1.2) µm. Conidia unicellular, subglobose to ellipsoidal, hyaline to yellow, (1.1–) 1.2 (–3.3) × (1.0–) 1.6 (–2.6) µ m (Figure 4 and Supplementary Figure S2).

Type: China, Heilongjiang province, Greater Hinggan mountains,   on   litters   of   forest,   September   2018,    Li Zeyu and Liu Boyang (holotype HMPHU 1244, culture ex-type CGMCC 19144).

Gene sequences ex-holotype: MN055703 (ITS), MN061635 (LSU), MN055706 (SSU), MN065770 (TEF), MN061672 (TUB), MN917170 (RPB1a), MT939494 (RPB2a).

Sexual morph: not observed

 Habitat: forest litters

Distribution: Greater Hinggan mountains, Heilongjiang province, China.

Notes: P. hingganense is compared with P. changbaiense, Keithomyces carneum, Ma. marquandii, Metarhizium globosum, Metarhizium minus, and Metarhizium blattodeae. The phialides arrangement of K. carneum and Ma. marquandii is Paecilomyces-like, but P. hingganense possesses candelabrum- like conidiophores. The conidia of M. blattodeae, M. globose, and M. minus are bigger than those in P. hingganense and have different shapes. P. changbaiense and P. hingganense differ mainly in the shape of their phialides and colony characteristics. The phialides of P. changbaiense are cylindrical with a short neck, while those of P. hingganense are obpyriform with a long distinct neck. Colonies of P. changbaiense are white on PDA compared to the yellow colonies of P. hingganense (Figure 4). A detailed list of the diagnostic features and sequence similarities in comparison with related species can be found in Table 2 and Figure 2.

FIGURE 2 | Pairwise nucleotide sequence similarities (in %) for 7-locus from Parametarhizium spp. and morphologically similar species.

FIGURE 4 | Morphological characters of Parametarhizium changbaiense [from ex-holotype China General Microbiological Culture Collection Center (CGMCC) 19143] and Parametarhizium hingganense (from ex-holotype CGMCC 19144). (A,B) The front and reverse of a P. changbaiense colony on PDA after 14 days at 25C. (C,D) The phialides and conidia of P. changbaiense. (E) Rhopalosiphum maidis infected by P. changbaiense. (F,G) The front and reverse of a P. hingganense colony on PDA after 14 days at 25C. (H,I) The phialides and conidia of P. hingganense. (J) R. maidis infected by P. hingganense.

Figure S2. Colonies of Parametarhizium changbaiense and Parametarhizium hingganense on different media. (A-C) P. changbaiense colonies (front left side, reverse right side) on Sabouraud dextrose agar with yeast extract (SDAY), Malt extract powder (MEA), and Oatmeal agar (OA). (D-F) P. hingganense colonies (front left side, reverse right side) on SDAY, MEA, and OA.