Akanthomyces kunmingensis Hong Yu bis, Y. Wang & Z.Q. 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 kunmingensis Hong Yu bis, Y. Wang & Z.Q. Wang sp. nov.

Fig. 2

Etymology.

Named after the location, Kunming City, where the species was collected.

Type.

China. Yunnan Province, Kunming City, Wild Duck Lake Forest Park (25.2181°N, 102.8503°E, 2100 m above sea level), on a spider on a dead stem, 14 August 2018, collected by Yao Wang (holotype: YHH 16988; ex-type living culture: YFCC 1808940) .

Description.

Sexual morph: Undetermined. Asexual morph: Synnemata arising from spider body, cream to light yellow, erect, irregularly branched, producing a mass of conidia at the upper apex, powdery and floccose. Colonies on PDA reaching 15-20 mm in diameter after 14 days at 25 °C, circular, white and fluffy mycelium, middle bulge, reverse pale yellow to light brown. Hyphae smooth-walled, branched, septate, hyaline, 0.5-2.8 μm wide. Conidiophores smooth-walled, cylindrical, solitary, sometimes verticillate, 4.3-9.5 × 1.2-2.0 μm (n = 30). Phialides consisting of a cylindrical, somewhat inflated base, verticillate on conidiophores, usually in whorls of 4-5 or solitary on hyphae, 6.2-29.4 × 1.1-2.5 μm (n = 30). Conidia smooth and hyaline, ellipsoidal to long oval, one-celled, 1.9-3.5 × 1.1-1.8 μm (n = 50), often in chains. Size and shape of phialides and conidia similar in culture and on natural substratum.

Host.

Spider ( Araneae ).

Habit.

On spiders on dead stems.

Distribution.

Kunming City, Yunnan Province, China.

Other material examined.

China. Yunnan Province, Kunming City, Songming County, Dashao Village (25.3924°N, 102.5589°E, 2700 m above sea level), on a spider on a dead stem, 12 August 2017, Yao Wang (YHH 2301006; living culture: YFCC 1708939) .

Commentary.

In regard to phylogenetic relationships, Akanthomyces kunmingensis forms a distinct lineage in the genus Akanthomyces with high credible support (1/100%/100%) and it is closely related to A. sulphureus and A. waltergamsii (Fig. 1 ). Morphologically, A. kunmingensis is so similar to A. waltergamsii that it was once referred to as A. waltergamsii by Wang et al. (2020); however, a morphological observation revealed a significant difference of conidia shapes between A. kunmingensis and A. waltergamsii . Akanthomyces kunmingensis usually produces a variety of shapes of conidia (viz. spherical, ellipsoidal to long oval or fusiform), while A. waltergamsii produces only ellipsoidal and fusiform conidia. Moreover, A. kunmingensis can be distinguished from A. sulphureus and A. waltergamsii by its longer phialides (6.2-29.4 µm) and smaller conidia (1.9-3.5 × 1.1-1.8 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 2. Morphology of Akanthomyces kunmingensis A the type specimen (YHH 16988) B culture character on PDA medium C conidiogenous structures on the host D-H conidiophores, conidiogenous cells and conidia I conidia. Scale bars: 3 mm (A); 10 mm (B); 10 µm (C, E, F); 5 µm (D); 2 µm (G-I).