Azygosporus macropapillatus B. Huang & Y. Nie, 2021

Cai 1, Yue, Nie *, Yong, Zhao, Heng, Wang, ZiMin, Zhou, ZhengYu, Liu, XiaoYong & Huang, Bo, 2021, Azygosporus gen. nov., a synapmorphic clade in the family Ancylistaceae, MycoKeys 85, pp. 161-172 : 161

Azygosporus macropapillatus B. Huang & Y. Nie sp. nov.

Fig. 2

Etymology.

macropapillatus (Lat.), named by its prominent basal papilla.

Host and known distribution.

Isolated from plant debris and mosses in Anhui Province, China.

Type specimens examined.

China, Anhui Province, Ningguo City, Fangtang Town , 30°30'57" N, 118°42'17" E, from plant debris, 12 Nov 2020, Y. Nie, HMAS 350621, holotype, culture ex-holotype CGMCC 3.16068 (= RCEF 6680). GenBank: nrLSU = MZ542006 ; TEF1 = MZ555650 ; mtSSU = MZ542279 .

Additional specimens examined.

China, Anhui Province, Jinzhai County, Tiantangzhai National Forest Park, 31°20'68" N, 115°81'25" E, from mosses, 6 Nov 2008, C.F. Wang, culture RCEF 4444. GenBank: nrLSU = MZ542004 ; TEF1 = MZ555648 ; mtSSU = MZ542277 . China, Anhui Province, Jinzhai County, Tiantangzhai National Forest Park, 31°17'34" N, 115°78'13" E, from plant debris, 3 Dec 2015, Y. Nie and X.X. Tang, culture RCEF 6334. GenBank: nrLSU = MZ542005 ; TEF1 = MZ555649 ; mtSSU = MZ542278 .

Description.

Colonies white, reaching ca 17.0-23.0 mm diameter on PDA after 3 d at 21°C. Mycelia colorless, 3.0-7.5 µm wide, usually unbranched at the colony edge. Primary conidiophores colorless, without widening upward near the tip, unbranched and producing a single conidium, 37.0-150.0 × 5.0-8.5 µm. Primary conidia forcibly discharged, colorless, subglobose, 12.0-19.0 µm wide and 16.5-22.5 µm long, most primary conidia possessed a prominent basal papilla 5.0-10.0 µm wide and 7.5-10.0 µm long. Secondary conidia arising from the primary ones with a similar shape and a smaller size. Resting spores (azygospores) observed after 10 d, and the young spores formed in the middle region of the old hyphal segments. The young spores enlarge gradually to form mature azygpspores with less thickening. Mature azygospores colorless, subglobose 25.0-30.0 × 27.0-34.0 μm with a wall 0.5-1.0 μm thick.

Notes.

Morphologically, Azygosporus macropapillatus sp. nov. has conidial dimensions similar to six Conidiobolus s.l. species without capilliconidia and microconidia: C. parvus , M. nodosus , M. paulus , N. kunyushanensis , N. lamprauges , and N. pachyzygosporus ( Drechsler 1953, 1957, 1962; Srinivasan and Thirumalachar 1967; Nie et al. 2018, 2021). However, A. macropapillatus sp. nov. produces a prominent basal papilla of primary conidia that differs from other related species (see detailed morphological comparisons in Table 2 ). A. macropapillatus sp. nov. forms azygospores most closely resembling those of C. parvus (= A. parvus ), which is its closest known relative with robust support (100/100/1.00). A. macropapillatus sp. nov. is distinguished from C. parvus (= A. parvus ) by its longer primary conidiophore and its prominent basal papilla.

Figures

Figure 2. Morphological characters of Azygosporus macropapillatus: a) colony on PDA after 3 d at 21 ° C, b) mycelia rarely branched at the colony edge, c-f) primary conidiophores bearing primary conidia, g-h) Primary conidia with prominent basal papillum, j-k) secondary conidia arising from primary conidia, i-m) azygospores formed in the middle region of the old hyphal segment, n) immature azygospore, and o-q) mature azygospores. Scale bars: a) 10 mm, b) 100 μm, and c-q) 20 μm.