Linnemannia ovalispora X. Y. Ji, H. Zhao & X. Y. Liu, 2025

Ji, Xin-Yu, Ding, Zi-Ying, Liu, Wen-Xiu, Li, Fei, Zhao, Heng, Wang, Shi & Liu, Xiao-Yong, 2025, Unveiling species diversity within Mortierellomycota from China X: Three new species in Linnemannia and one in Mortierella, MycoKeys 125, pp. 245-262 : 245-262

Linnemannia ovalispora X. Y. Ji, H. Zhao & X. Y. Liu sp. nov.

Fig. 4

Type.

China • Yunnan Province, Yuxi City, Research and service area of Hongta District ( 24°15'41"N, 102°28'58"E, altitude 1632.18 m), from soil, 15 March 2024, X. Y. Ji, holotype HMAS 354072 , ex-holotype living culture CGMCC 3.28891 (= XG 09524-11-1 ) .

Etymology.

The epithet ovalispora (Lat.) refers to the oval sporangiospores.

Description.

Colonies on MEA at 16 ° C for 5 d, attaining 60 mm diameter, moderately fast growing with a rate of 12 mm / d, garlic smell, with a thin white film and few aerial mycelia. Hyphae hyaline, 1.4–4.5 µm in diameter (n = 15, x ̄ = 2.4). Sporangiospores transparent, mostly oval, 3.8–9.8 × 2.7–6.2 µm (n = 15, x ̄ = 6.7 × 4.3 µm). Chlamydospores present, gastric-shaped, 7.7–9.2 × 5.7–8.8 µm (n = 15, x ̄ = 8.4 × 7.3 µm). Zygospores absent.

Temperature requirements.

Minimum growth temperature 4 ° C and maximum growth temperature 29 ° C.

Additional strains examined.

China • Yunnan Province, Yuxi City, Research and service area of Hongta District ( 24°15'41"N, 102°28'58"E, altitude 1632.18 m), from soil, 15 March 2024, X. Y. Ji, living culture XG 09524-11-2 .

Notes.

Integrated phylogenetic analysis of the ITS, LSU, SSU, RPB 1, and Act gene regions revealed that the new species Linnemannia ovalispora is closely related to L. rugosa (Fig. 2 ). The new species is distinguished from L. rugosa by 82 / 630 and 80 / 1059 characters in ITS and LSU sequences, respectively. In terms of sporangiospores, the new species is oval and smooth, unlike L. rugosa , which is round and coarse. In the shape of chlamydospores, the new species is gastric-shaped, while L. rugosa is elongated.

Figures

Figure 2. The Maximum Likelihood phylogenetic tree for the genus Mortierella based on combined ITS, LSU, SSU, RPB 1, and Act sequences with Umbelopsis autotrophica as an outgroup. Node supports are indicated by two metrics: Maximum Likelihood Bootstrap Values (left, MLBV ≥ 70 %) and Bayesian Inference Posterior Probabilities (right, BIPP ≥ 0.90), separated by a slash (/). Novel species are emphasized in red. Bold entries with asterisks (*) denote ex-type or ex-holotype strains. The scale bar in the lower left represents 0.1 substitutions per site.

Figure 4. Linnemannia ovalispora ex-holotype CGMCC 3.28891. a, b. Colonies on MEA (a. obverse; b. reverse); c, d. Chlamydospores; e – g. Sporangiospores. Scale bars: 10 µm (c – g).