Akanthomyces laosensis Hong Yu bis & Y. Wang, 2024

Wang, Yao, Wang, Zhi-Qin, Luo, Run, Souvanhnachit, Sisommay, Thanarut, Chinnapan, Dao, Van-Minh & Yu, Hong, 2024, Species diversity and major host / substrate associations of the genus Akanthomyces (Hypocreales, Cordycipitaceae), MycoKeys 101, pp. 113-141 : 113

Akanthomyces laosensis Hong Yu bis & Y. Wang sp. nov.

Fig. 3

Etymology.

Named after the location, Laos, where the species was collected.

Type.

Laos. Oudomxay Province, Muang Xay County, Nagang Village (20.7143°N, 102.0957°E, 698 m above sea level), on the adult of Noctuidae on the underside of a dicotyledonous leaf, 5 October 2019, collected by Yao Wang (holotype: YHH 2301008; ex-holotype living culture: YFCC 1910941) .

Description.

Sexual morph: Undetermined. Asexual morph: Specimens examined in this study can be found on the underside of dicotyledonous leaves. Synnemata arose at the head and in the middle of the host body, white, up to 15.6 mm long and 0.6-1.3 mm wide, rarely branched, feathery to clavate with acute or blunt ends. Colonies on PDA moderately fast-growing at 25 °C, reaching 23-26 mm in diameter in 14 days, circular, flat, white in the middle with a light yellow edge, reverse light yellow. Hyphae smooth-walled, branched, septate, hyaline, 0.8-3.5 µm wide. Conidiogenous cells monophialidic, produced along the synnemata or solitary on hyphae in culture. Phialides smooth-walled, hyaline, cylindrical, 11.5-30.0 × 2.0-4.2 µm (n = 30). Conidia smooth and hyaline, cylindrical or long oval, one-celled, 4.1-9.8 × 2.3-4.2 µm (n = 30). Size and shape of phialides and conidia similar in culture and on natural substratum.

Host.

Adult moth ( Noctuidae , Lepidoptera ).

Habit.

On the adults of Noctuidae sp. on the underside of leaves of plants.

Distribution.

Muang Xay County, Oudomxay Province, Laos.

Other material examined.

Laos. Oudomxay Province, Muang Xay County, Nam Kit Park (20.6651°N, 102.0007°E, 695 m above sea level), on an adult moth on the underside of a leaf, 1 October 2019, Yao Wang (YHH 2301000; living culture: YFCC 1910942) .

Commentary.

Phylogenetically, Akanthomyces laosensis forms a distinct lineage and is closely related to A. pyralidarum with strong statistical support (1/99%/89%) (Fig. 1 ). Morphologically, A. laosensis is distinctly different from A. pyralidarum because of its longer synnemata (up to 15.6 mm). Furthermore, A. laosensis was determined to occur on an adult of Noctuidae sp., while A. pyralidarum was located on an adult of Pyralidae sp. In fact, the species is easily distinguished from other known species in the genus of Akanthomyces by its longer phialides (11.5-30.0 µm) and larger conidia (4.1-9.8 × 2.3-4.2 µm) (Table 3 ).

Figures

Figure 1. Phylogenetic tree of Akanthomyces species, based on combined partial ITS + nrLSU + TEF + RPB 1 + RPB 2 sequences. Numbers at the branches indicate support values (BI-PP / IQ-TREE-BS / RAxML-BS) above 0.7 / 70 % / 70 %. Ex-type materials are marked with " T ". Isolates in bold type are those analysed in this study.

Figure 3. Morphology of Akanthomyces laosensis A, B fungus on adult moth C long synnemata D culture character on PDA medium E-H conidiophores, conidiogenous cells and conidia I conidia from long synnemata. Scale bars: 10 mm (A, B); 5 mm (C); 20 mm (D); 20 µm (E-G); 10 µm (H); 5 µm (I).