Conidiobolus marcoconidius B. Huang & Y. Nie sp. nov.

Fig. 3

Etymology.

marcoconidius (Lat.), referring to its large primary conidia.

Known distribution.

Anhui Provinces, China.

Typification.

China, Anhui Province, Hefei City, Dashushan National Forest Park, 31 ° 84 ′ N, 117 ° 17 ′ E, from plant debris, 15 Mar. 2022, Y. Yin, holotype DSS 20220315. Ex-type culture RCEF 6918. GenBank: nucLSU = PP 034289; EFL = PP 035213; mtSSU = PP 034293.

Additional specimens examined.

China, Anhui Province, Hefei City, Binhu National Forest Park, 31 ° 73 ' N, 117 ° 38 ' E, from plant debris, 10 May 2022, Y. Yin ,, culture RCEF 7412. GenBank: GenBank: nucLSU = PP 034290; EFL = PP 035214; mtSSU = PP 034294.

Description.

Colonies on PDA at 21 ° C after 3 d white, reaching ca 8 mm in diameter. Mycelia colorless, unbranched at the edge of colony, distended to a width of 9–20 μm segment after 5 d. Primary conidiophores unbranched, slightly curved at the tip, producing a single primary conidium, without widening upward near the tip, 105–230 × 10–16 μm. Primary conidia forcibly discharged, mostly globose, sometimes obovoid, 45–67 × 42–58 μm, with a sharp or round papilla, 13–22 μm wide, 4–13 μm long. Secondary conidia arising from primary conidia, with a short or long secondary condiophore, similar and smaller to the primary conidia. Secondary conidiophores branched at the base or tip, thus bearing 2 secondary conidia at each tip. Sometimes form 2–5 secondary conidia like “ tomatoes on sticks ” from small to large at each branch. Microconidia not observed on the PDA culture and on the 2 % water agar. Zygospores formed between adjacent segments after 7 days, smooth, globose, 30–45 μm in diameter, with a 2–4 μm thick wall.

Notes.

Conidiobolus marcoconidius is distinguished morphologically by its larger primary conidia compared to other Conidiobolus s. s. species, with the exception of C. coronatus (King 1977). Notably, it can be readily differentiated from C. coronatus by the absence of villose spores (Batko 1964). Additionally, C. marcoconidius is characterized by secondary conidiophores that branch at the base, giving rise to 2–5 secondary conidia resembling “ tomatoes on sticks ” at each branch, varying in size from small to large. In the phylogenetic tree, it forms a discrete clade, setting it apart from other Conidiobolus s. s. species.