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

Fig. 4

Etymology.

Referring to macromorphological resemblance of A. noctuidarum , but A. pseudonoctuidarum is phylogenetically distinct.

Type.

Thailand. Chiang Mai Province, Chiang Mai City, Sansai District, Maejo Farm (18.9177°N, 99.0520°E, 317 m above sea level), on the adult of Noctuidae on the underside of a dicotyledonous leaf, 22 August 2018, collected by Hong Yu (holotype: YHH 2301010; ex-type living culture: YFCC 1808943) .

Description.

Sexual morph: Undetermined. Asexual morph: Synnemata arising from moth body, cream to light yellow, erect, simple, cylindrical to clavate, 800-2000 × 120-350 µm. Conidia and reproductive structures on natural substratum not observed. Colonies on PDA moderately fast-growing at 25 °C, reaching a diameter of 25-28 mm within 14 days, circular, flat to raised, white and fluffy mycelium, reverse cream to pale yellow. Hypha smooth-walled, hyaline, septate, 1.0-2.9 µm wide. Conidiophores smooth-walled, cylindrical, solitary, 6.5-13.8 × 1.8-3.6 µm (n = 30). Conidiogenous cells monophialidic or polyphialidic. Phialides verticillate, usually in whorls of 2-3 or solitary on hyphae, cylindrical with papillate end, hyaline, 6.8-26.0 × 2.1-3.6 µm (n = 30). Conidia smooth and hyaline, ellipsoidal to long oval, one-celled, 2.6-6.4 × 1.5-2.2 µm (n = 30).

Host.

Adult moth ( Noctuidae , Lepidoptera ).

Habit.

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

Distribution.

Chiang Mai City, Chiang Mai Province, Thailand.

Other material examined.

Thailand, Chiang Mai Province, Chiang Mai City, Mae Rim District, Queen Sirikit Botanic Garden (18.8990°N, 98.8605°E, 536 m above sea level), on an adult of Noctuidae , 26 August 2018, collected by Yao Wang (YHH 2301011; living culture: YFCC 1808944) .

Commentary.

Akanthomyces pseudonoctuidarum is similar to its phylogenetically closely-related species A. noctuidarum in macromorphology. They have the same hosts (the adults of Noctuidae sp.) and Isaria -like asexual conidiogenous structures, producing cream or light yellow synnemata. However, A. pseudonoctuidarum is easily recognised by its larger synnemata (800-2000 × 120-350 µm), longer phialides (6.8-26.0 µm) and larger conidia (2.6-6.4 × 1.5-2.2 µm) (Table 3 ). It was easily distinguished phylogenetically from A. noctuidarum (Fig. 1 ; 1 /97%/85%). Both the morphological study and phylogenetic analyses of combined ITS, nrLSU, TEF, RPB1 and RPB2 sequence data supported that this fungus is a distinct species in the genus Akanthomyces .

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 4. Morphology of Akanthomyces pseudonoctuidarum A adult moth infected by A. pseudonoctuidarum B, C culture character on PDA medium D-H conidiophores, conidiogenous cells and conidia I conidia. Scale bars: 2 mm (A); 20 mm (B, C); 10 µm (D-I).