Hirsutella kuankuoshuiensis X. Zou, J.J. Qu & Z.Q. Liang, 2021

Qu, Jiaojiao, Zou, Xiao, Cao, Wei, Xu, Zhongshun & Liang, Zongqi, 2021, Two new species of Hirsutella (Ophiocordycipitaceae, Sordariomycetes) that are parasitic on lepidopteran insects from China, MycoKeys 82, pp. 81-96 : 81

Hirsutella kuankuoshuiensis X. Zou, J.J. Qu & Z.Q. Liang sp. nov.

Fig. 3

Diagnosis.

Hirsutella kuankuoshuiensis differs from other species in this genus primarily by its clavate, narrow fusiform or botuliform conidia and subulate or slender columnar phialide.

Type.

China, Guizhou Province, Suiyang County, Kuankuoshui Nature Reserve (28°08'N, 107°02'E, approximately 1400 m a.s.l.), July 2012, collected by X. Zou. The holotype has been deposited at KIB (HKAS112885). Sequences from isolated strains (GZUIFR-2012KKS3-1, GZUIFR-2012KKS3-2 and GZUIFR-2012KKS3-3) have been deposited in GenBank .

Description.

Synnemata are single, extending from the head of insect; 8.6 cm long, dark brown and changing to brown towards the apex; no conidiation was observed (Fig. 3A ). The fungus spreads slowly on PDA agar at 20-22 °C and grows to a diam. of 22-30 mm after 14 d; the colony is round, centre of surface with brown dense bulges and grey-white sparse flocculent aerial hyphae. Colony margin is flat with radial groove; a large amount of brown pigment secreted into the medium causes the back of colony to appear dark brown; thickness 10-12 mm (Fig. 3B, C ). Mycelium hyaline, smooth, septate, 1.5-3.0 μm wide. Conidiogenous cells monophialidic, hyaline, borne perpendicular or at an acute angle to the subtending hyphae. Phialides subulate or slender columnar, tapering gradually to a long and narrow neck, 30-45 × 1-3 μm long. Conidia clavate, narrow fusiform or botuliform without a diaphragm, 9.9-12.6 × 2.7-4.5 μm, single- or double-enveloped in a hyaline mucus, thickness 2.0-3.0 μm (Fig. 3D-J ).

Etymology.

Referring to the locality of the specimen, kuankuoshui (Lat. ' Hirsutella kuankuoshuiensis ').

Host.

Lepidoptera larva.

Habitat and distribution.

On the decaying leaves of broadleaved forests, Guizhou Province, China.

Teleomorph.

Unknown.

Remarks.

This species possesses two types of conidiogenous cells and long fusiform or clavate without diaphragm conidia (9.9-12.6 × 2.7-4.5 μm), which is extremely rare in Hirsutella species. In addition, H. kuankuoshuiensis could produce long thin synnemata on the culture media that contain few or no conidia.

Figures

Figure 3. Morphological characteristics of Hirsutella kuankuoshuiensis A the insect specimens with single and thin synnemata (HKAS 112885) B, C colonial morphology on PDA agar media for 20 d B shows the front of the colony and C shows the back of the colony D-G LM images showing conidiogenous cells and conidia D, E the structure of conidiogenous cells on mycelia F the images of conidiogenous cells on synnemata (optical microscope) H-J conidial morphology (LM) G conidia with mucilage (SEM). Scale bars: 10 mm (A-C); bar of G was shown in the figure; the rest of the bars were 10 μm. LM, light microscopy; PDA, potato dextrose agar; SEM, scanning electron microscopy.