Metarhizium lymantriidae Z.H. Chen & L. Xu, sp. nov. (Figure 2)

MycoBank no.: MB 843060

Etymology: Named after the host belonging to the family Lymantriidae (Lepidoptera) .

Colonies on PDA medium reaching 16 mm in diameter after 16 days of cultivation at 25 °C, white to light green. Hyphae septate, hyaline, branched, smooth-walled, 0.9–1.6 (X = 1.2 ± 0.2) µm wide. Phialides cylindrical or ampuliform, smooth-walled, hyaline, 6.9–21.5 × 0.9–1.5 (X = 10.2 ± 4.6 × 1.2 ± 0.2) µm. Conidia oval or ellipsoidal, forming chain in culture, hyaline, aseptate, smooth, 2.1–3.5 × 1.4–2.1 (X = 2.7 ± 0.2 × 1.7 ± 0.2) µm.

Material examined: CHINA. Yunnan Province: the Gaoligong Mountains, on the larva of Lymantriidae, 18 May 2017, Zi-Hong Chen (BUM 818, holotype; KUNCC 4991, ex-type living culture); Baoshan City, on the larva of Lymantriidae, 24 June 2017, Ling Xu (BUM 830, living culture) .

Notes: Metarhizium lymantriidae was close to M. rileyi and M. dendrolimatilis in the phylogenetic tree. It was difficult to distinguish M. lymantriidae from M. rileyi by the conidia color (Fig. 2 A, B). Isolates of M. lymantriidae grew slowly on PDA medium, similar to M. rileyi . M. dendrolimatilis grew moderately faster than M. lymantriidae and M. rileyi . The distinctiveness of M. lymantriidae was indicated by that its conidia size (2.1–3.5 × 1.4–2.1 µm) was smaller than M. rileyi (3.5–4.5 × 2.0–3.1 µm) and M. dendrolimatilis (3.2–5.4 × 2.2–3.2 µm). The phialides of M. lymantriidae (6.9–21.5 × 0.9–1.5 µm) was more slender than M. rileyi (4.7–6.5 × 2.3–3.0 µm) (Samson 1974) and M. dendrolimatilis (4.3–5.4 × 1.2–3.4 µm). In the wild, M. lymantriidae infected the larva of tussock moth, M. dendrolimatilis infected the larva of Dendrolimus sp., while M. rileyi could infect the larva of noctuid, beetle and sawfly.