Backusella variispora H. Zhao & X. Y. Liu, 2024

Zhao, Heng, Nie, Yong, Huang, Bo & Liu, Xiao-Yong, 2024, Unveiling species diversity within early-diverging fungi from China I: three new species of Backusella (Backusellaceae, Mucoromycota), MycoKeys 109, pp. 285-304 : 285-304

Backusella variispora H. Zhao & X. Y. Liu sp. nov.

Fig. 4

Etymology.

variispora (Lat.) refers to the species having an uneven size of sporangiospores.

Holotype.

HMAS 352891 .

Colonies on PDA at 25 ° C for 4 days, reaching 90 mm in diameter, more than 15 mm high, flat, granulate, initially white, soon becoming pale mouse-grey, irregular at margin. Hyphae aseptate at first, septate with age, hyaline, 4.5–11.5 μm in diameter. Rhizoids absent. Stolons absent. Long sporangiophores arising directly from substrate mycelia, transitorily curved, monopodially branched, with large terminal sporangia, erect, bent or curved. Sporangia globose, hyaline to brownish, wall rough with spines, deliquescent, rough, multi-spored, with more than 20 sporangiospores per sporangium, 30.5–60.0 μm in diameter. Short sporangiophores simple or sympodial, ending with a multi-spored. Multi-spored sporangiola subglobose to globose, with numerous spines, hyaline, containing 5–10 sporangiospores, persistent-walled, 14.5–26.0 μm in diameter. Apophyses absent. Collars absent. Columellae hemispherical, subglobose to globose, hyaline, 21.0–32.5 × 20.0–33.0 μm in long sporangiophores, conical and hemispherical, hyaline, 14.5–18.5 × 14.0–18.0 μm in short sporangiophores. Sporangiospores subglobose to globose, hyaline, with droplets, 5.0–16.0 μm in diameter. Azygosporangia absent. Chlamydospores absent. Zygospores absent.

Materials examined.

China • Hainan Province, Ledong Li Autonomous County, 18 ° 42 ' 35 " N, 108 ° 52 ' 36 " E, from soil sample, 11 April 2023, (holotype HMAS 352891 , living ex-holotype culture HZ 69) • Changjiang Li Autonomous County, 19 ° 7 ' 18 " N, 109 ° 7 ' 7 " E, from soil sample, 12 April 2023, Heng Zhao (living cultures HZ 105, HZ 195, and HZ 365) • Lingshui Li Autonomous County, 18 ° 42 ' 8 " N, 109 ° 50 ' 13 " E, from forest soil sample, 9 April 2023, Heng Zhao (living cultures HZ 141 and HZ 286) .

GenBank accession numbers.

ITS, PP 477395 – PP 477400; LSU, PP 477405 – PP 477410, RPB 1, PP 709511 and PP 709515.

Maximum growth temperature.

35 ° C.

Figures

Figure 4. Morphologies of Backusella variispora ex-holotype HZ 69 a, b colonies on PDA (a obverse b reverse) c – e long sporangiophores with multi-spored sporangia f, g short sporangiophores with multi-spored sporangia h – j sporophore with columellae k sporangiospores. Scale bars: 10 μm (c, f – k); 20 μm (d, e).