Gongronella apophysata Yi Xin Wang, H. Zhao & X. Y. Liu, 2024

Wang, Yi-Xin, Zhao, Heng, Jiang, Yang, Liu, Xin-Ye, Tao, Meng-Fei & Liu, Xiao-Yong, 2024, Unveiling species diversity within early-diverging fungi from China III: Six new species and a new record of Gongronella (Cunninghamellaceae, Mucoromycota), MycoKeys 110, pp. 287-317 : 287-317

Gongronella apophysata Yi Xin Wang, H. Zhao & X. Y. Liu sp. nov.

Fig. 3

Etymology.

The epithet “ apophysata ” (Latin) refers to various shapes of apophyses.

Type.

China • Sichuan Province, Emeishan City, Leshan City, Ehong Road, near the Xu family residence (29.59211 ° N, 103.37776 ° E), from soil sample, 25 June 2023, Yi-Xin Wang (holotype HMAS 352728 , ex-holotype strain CGMCC 3.27031 ) .

Description.

Colonies growing slowly on PDA in darkness at 25 ° C, reaching 35.8–42.4 mm in diameter in seven days, white, irregular at edge and cottony in the centrr, reversely milky white. Rhizoids hyaline, branched, irregularly shaped. Stolons absent. Sporangiophores on aerial mycelia, erect or slightly curved, unbranched or slightly branched (1–2 times), 11.2–190.9 × 1.6–3.9 μm, hyaline, smooth, mostly aseptate or one-septate, occasionally two-septate. Sterile (aborted) sporangia predominantly on the top of short lateral branches of sporangiophores, gourd-shaped, 14.0 × 8.3 μm. Fertile sporangia hyaline or light yellow, spherical, 12.5–40.5 μm in diameter, smooth and deliquescent-walled, leaving a collar after releasing sporangiospores. Columellae elliptic, 2.6–4.0 × 2.1–5.5 μm, sub-hemispherical, 1.4–2.7 × 2.2–4.3 μm, hyaline, smooth. Apophyses hyaline, smooth, variously shaped, mostly ellipsoidal to olive-shaped, 2.3–17.3 × 2.4–10.0 μm, partially subglobose, 4.6–10.2 × 4.3–10.0 μm, occasionally gourd-shaped, 11.4 × 4.9 μm. Sporangiospores not uniform, hyaline, smooth, mostly reniform, 3.2–5.5 × 1.7–3.1 μm, ovoid, 2.5–3.7 × 1.7–2.6 μm, occasionally subglobose, 1.7–2.5 μm. Chlamydospores present, not uniform, gourd-shaped, ellipsoidal and suborbicular, mostly gourd-shaped, 23.5–35.4 × 10.8–14.0 μm, partially ellipsoidal, 18.6–21.4 × 10.3–18.5 μm. Giant cells in the rhizoids, intercalary, globose, 4.4–10.5 μm in diameter. Zygospores not found.

Additional specimen examined.

China • Sichuan Province, Emeishan City, Leshan City, Ehong Road, near the Xu family residence (29.59211 ° N, 103.37776 ° E), from soil sample, 25 June 2023, Yi-Xin Wang (living culture SAUCC 4846-3 ) .

GenBank accession numbers.

CGMCC 3.27031 ( ITS, PP 195853; LSU, PP 195954; TEF, PP 850099; ACT, PP 933947; RPB 1, PP 842878), SAUCC 4846-3 ( ITS, PP 195854; LSU, PP 195956; TEF, PP 850100; ACT, PP 933948; RPB 1, PP 842877).

Notes.

Based on phylogenetic analyses of ITS + LSU + TEF + ACT + RPB 1 sequences, the two isolates of the new species Gongronella apophysata form an independent clade with high support ( MLBV = 98; Fig. 1 ), which is closely related to G. zunyiensis . In ITS, G. apophysata differs from the type species of G. zunyiensis by 13 base pairs. This new species differs morphologically from G. zunyiensis in sporangium, columellae, apophyses and chlamydospore ( Dong et al. 2019). G. apophysata has larger sporangia than G. zunyiensis (12.5–40.5 μm vs. 11.0–19.5 μm). G. apophysata differs from G. zunyiensis in the shape of columellae, the former being elliptic and the latter being hemispherical and globose. As for apophyses, G. apophysata and G. zunyiensis are remarkably different in shape and size, the former variously shaped, mostly ellipsoidal to olivary, 2.3–17.3 × 2.4–10.0 μm, partially subglobose, 4.6–10.2 × 4.3–10.0 μm, occasionally gourd-shaped, 11.4 × 4.9 μm and the latter hemispherical, 1.5–3.5 × 1.0–3.0 μm. G. apophysata is remarkably different from G. zunyiensis in shape and size of chlamydospores, the former being not uniform, mostly gourd-shaped, 23.5–35.4 × 10.8–14.0 μm, partially ellipsoidal, 18.6–21.4 × 10.3–18.5 μm and the latter being terminal or lateral, globose or subglobose, 7.0–10.5 μm in diameter. Combining morphological and molecular phylogenetic analyses, we classified the two isolates together as a new species G. apophysata allied to G. zunyiensis .

Figures

Figure 1. A Maximum Likelihood (ML) phylogenetic consensus tree inferred from DNA sequences of ITS, LSU, TEF, ACT and RPB 1, showing relationships amongst species of Gongronella with Cunninghamella echinulata CBS 156.28 as outgroup. The Maximum Likelihood bootstrap value (MLBV) and Bayesian Inference posterior probability (BIPP) are successively shown at the nodes and separated by a slash “ / ”. Strains marked with a star “ * ” are ex-types or ex-holotypes. The strains isolated and sequenced in this study are shown in red. Branches shortened to fit the page are represented by double slashes “ // ” and folds “ × ”. The scale in the bottom centre indicates 0.2 substitutions per site.

Figure 3. Gongronella apophysata ex-holotype CGMCC 3.27031 a, b colonies on PDA (a obverse b reverse) c an unbranched sporangiophore with a fertile sporangium d an unbranched sporangiophore with an immature sporangium e – g columellae, collars, apophyses and septa h branched sporangiophores with columellae, collars and apophyses i branched sporangiophores with columellae, collars and apophyses j – l chlamydospores m giant cells n, o rhizoids p sporangiospores. Scale bars: 10 μm (c – p).