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

Fig. 5

Etymology.

“Subaraneicola” refers to morphologically resembling A. araneicola , but phylogenetically distinct.

Type.

China. Hunan Province, Huaihua City, Zhongpo National Forest Park (27.5724°N, 109.9664°E, 615 m above sea level), on a spider emerging from leaf litter on the forest floor, 10 July 2021, collected by Yao Wang (holotype: YHH 2301004; ex-type living culture: YFCC 2107937) .

Description.

Sexual morph: Undetermined. Asexual morph: Mycosed hosts covered by white to pale yellow mycelia, producing numerous powdery conidia, synnemata not observed. Colonies on PDA reaching 24-28 mm in diameter within 14 days at 25 °C, circular, white and fluffy mycelium in the centre, cottony with a raised mycelial density at the outer ring, reverse white to pale yellow. Hyphae smooth-walled, branched, septate, hyaline, 1.6-3.2 μm wide. Conidiophores smooth-walled, cylindrical, solitary, sometimes verticillate, 6.5-12.3 × 1.6-3.5 μm (n = 30). Conidiogenous cells monophialidic or polyphialidic. Phialides consisting of a cylindrical, somewhat inflated base, verticillate on conidiophores, usually in whorls of 2-5, or solitary on hyphae, 12.1-38.2 × 1.3-3.2 μm (n = 30). Conidia smooth and hyaline, ellipsoidal to long oval, one-celled, 3.0-5.4 × 1.8-3.4 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 or emerging from leaf litter on the forest floor.

Distribution.

Hunan and Yunnan Province, China.

Other material examined.

China, Yunnan Province, Kunming City, Wild Duck Lake Forest Park (25.1244°N, 102.8716°E, 1900 m above sea level), on a spider on a dead stem, 28 July 2021, Yao Wang (YHH 2301005; living culture: YFCC 2107938) .

Commentary.

Morphologically, Akanthomyces subaraneicola resembles the phylogenetic sister species A. araneicola . They were found to be parasitic on spiders ( Araneae ) and they are easily recognised by having white to pale yellow mycelia covering the hosts with a mass of conidia; however, our morphological observation revealed a significant difference in the shape and size of conidia between A. subaraneicola and A. araneicola . Akanthomyces subaraneicola usually produces large ellipsoidal to long oval conidia (3.0-5.4 × 1.8-3.4 μm), while A. araneicola produces small fusiform conidia (2.5-5.0 × 1.3-1.9 μm) (Table 3 ). In addition, molecular phylogenetic analyses indicated that they are distinct species (Fig. 1 ; 1 /100%/100%).

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 5. Morphology of Akanthomyces subaraneicola A, B fungus on spider C culture character on PDA medium D-H conidiophores, conidiogenous cells and conidia I conidia. Scale bars: 10 mm (A); 5 mm (B); 20 mm (C); 30 µm (D); 20 µm (E); 10 µm (F-I).