Samsoniella lepidopterorum W.H. Chen, Y.F. Han & Z.Q. Liang, 2020

Chen, Wan-Hao, Han, Yan-Feng, Liang, Jian-Dong, Tian, Wei-Yi & Liang, Zong-Qi, 2020, Morphological and phylogenetic characterisations reveal three new species of Samsoniella (Cordycipitaceae, Hypocreales) from Guizhou, China, MycoKeys 74, pp. 1-15 : 1

Samsoniella lepidopterorum W.H. Chen, Y.F. Han & Z.Q. Liang sp. nov. Fig. 5

Diagnosis.

Differs from Samsoniella coleopterorum by having larger, ellipsoidal phialide conidia and a host in the order Lepidoptera .

Type.

China, Guizhou Province, Rongjiang County (26°01'56.13"N, 108°24'48.06"E), October 2018, Wanhao Chen, holotype GZAC DL1007 = RJ1807, ex-type culture GZAC DL10071 = RJ18071. Sequences from isolated strain DL10071 have been deposited in GenBank with accession numbers: ITS = MN128076, RPB1 = MN101592, RPB2 = MN101593 and TEF = MN101594.

Description.

Colonies on PDA, 3.7-3.8 cm diam. in 14 d at 25 °C, white, consisting of a basal felt and cottony, floccose hyphal overgrowth, reverse yellowish. Prostrate hyphae smooth, septate, hyaline, 1.1-2.2 μm diam. Erect conidiophores usually arising from aerial hyphae, Isaria -like with phialides in whorls of two to four. Phialides 5.2-8.5 (-13.1) × 1.1-1.7 μm, with an ellipsoidal basal portion, tapering into a distinct neck. Conidia in chains, hyaline, fusiform to subglobose, 1-celled, 2.0-2.5 × 1.2-2.0 μm. Chlamydospores and synnemata not observed. Size and shape of phialides and conidia similar in culture and on natural substratum. Sexual state not observed.

Host.

Pupa, order Lepidoptera

Distribution.

Rongjiang County, Guizhou Province, China

Etymology.

Referring to its insect host, order Lepidoptera

Remarks.

Samsoniella lepidopterorum was easily identified as belonging to Samsoniella , based on the phylogenetic analyses (Fig. 1 ). Based on the combined dataset of ITS, RPB1, RPB2 and TEF sequences (Fig. 2 ) and the typical characteristics of Samsoniella species (Table 2 ), S. lepidopterorum has a close relationship with S. coleopterorum . However, S. lepidopterorum has larger, ellipsoidal phialide conidia and its pupa host is in the order Lepidoptera .

Figures

Figure 1. Phylogenetic relationships of the genus Samsoniella in Cordycipitaceae, based on multigene dataset (ITS, RPB 1, RPB 2 and TEF). Statistical support values (≥ 50 % / 0.5) are shown at the nodes for ML bootstrap support / BI posterior probabilities.

Figure 2. Phylogenetic relationships between the genus Samsoniella and closely-related species, based on multigene dataset (ITS, RPB 1, RPB 2 and TEF). Statistical support values (≥ 50 % / 0.5) are shown at the nodes for ML bootstrap support / BI posterior probabilities.

Figure 5. Samsoniella lepidopterorum A infected insect pupa (Lepidoptera) B, C top (B) and underside (C) of a colony cultured on PDA medium at 14 d D-G, I phialides and conidia in chains H conidia J conidiophore and phialides. Scale bars: 10 mm (B, C); 10 μm (D-J).