Simplicillium vallense W.H. Chen, Y.F. Han & J.D. Liang, 2024

Chen, Wan-Hao, Li, Dan, Shu, Hui-Lin, Liang, Jian-Dong & Han, Yan-Feng, 2024, Taxonomic and phylogenetic characterizations reveal two new species and a new record of Simplicillium (Cordycipitaceae, Hypocreales) from the Mayao River Valley, Guizhou, China, Phytotaxa 677 (3), pp. 278-288 : 283-284

Simplicillium vallense W.H. Chen, Y.F. Han & J.D. Liang , sp. nov. ( Fig. 3 )

MycoBank 849100

Etymology:— Referring to its location at Mayao River Valley.

Type:— CHINA. Guizhou: Qiannan Buyi and Miao Autonomous Prefecture, Duyun City , Mayao River Valley (26°22’8.3748”N, 107°23’16.96”E), on a dead spider (Araneae), 4 September 2021, Wanhao Chen , GZAC DY0992 (holotype) ; ex-type living culture, DY09921.

Colonies on PDA reaching a diameter of 28–32 mm in 14 days at 25 ℃, convex, with white velutinate aerial mycelium, reverse yellowish, especially in the middle, margin entire, soluble pigment not produced. Vegetative hyphae branched, hyaline, smooth-walled, septate, 1.1–3.6 μm wide. Phialides produced on aerial hyphae, always solitary, aseptate, hyaline, smooth-walled, relatively slender, and tapering toward the tip, 13.0–28.1 × 1.5–2.6 μm. Conidia in small globose heads at the apex of the phialides, hyaline, ellipsoidal to globose, aseptate, smooth-walled, 1-celled, 1.3–3.0 × 0.9–1.3 μm. Octahedral crystals absent. Sexual state not observed.

Host: —Spider (Araneae).

Additional strain examined: — CHINA. Guizhou: Qiannan Buyi and Miao Autonomous Prefecture, Duyun City, Mayao River Valley (26°22'8.3748"N, 107°23'16.96"E), on a dead spider (Araneae), 4 September 2021, Wanhao Chen, DY09922 (living culture).

Note: — Simplicillium vallense was easily identified as Simplicillium based on the blast result in NCBI and the phylogenetic analysis of combined datasets (ITS, LSU, TEF) ( Fig. 1 ), and has a close relationship with S. neolepidopterorum W.H. Chen, Y.F. Han, J.D. Liang & Z.Q. Liang. S. vallense was easily distinguished from S. neolepidopterorum (phialide, 34.1–44.3 × 1.0–1.7 μm, absence of conidial heads) by its shorter phialides (13.0– 28.1 × 1.5–2.6 μm) and presence of small globose conidial heads at the apex of the phialides. Jeewon and Hyde (2016) recommended that a minimum of>1.5% nucleotide differences in the ITS regions may be indicative of a new species. The pairwise dissimilarities of ITS sequences show 35 bp difference within 569 bp between S. vallense and S. neolepidopterorum (6.15%). Thus, the morphological characteristics and molecular phylogenetic results support S. vallense as a new species.

Figures

FIGURE 1. Phylogenetic relationships among the new strains and species of Simplicillium based on a multigene dataset (ITS, LSU and TEF). Statistical support values (≥ 50%/0.5) are shown at the nodes for maximum likelihood bootstrap support/Bayesian inference posterior probabilities.

FIGURE 3. Simplicillium vallense A infected spider B, C PDA-containing culture plate showing B the front and C reverse sides of the colony D–J phialides, conidia in chains and conidia. Scale bars: 10 mm (B, C); 10 μm (D–J).