Botryoconidia globosus X. Yu. Zhang, Q. Y. Zhang & B. Fan, 2025

Botryoconidia globosus X. Yu. Zhang, Q. Y. Zhang & B. Fan sp. nov.

Fig. 11 View Figure 11

Etymology.

Derived from the Latin word “ globosus ” indicating that the Conidia is spherical.

Type.

CHINA • Jiangsu Province, Nanjing, Nanjing Forestry University, Baima Campus , fungal endophytes from Pinus elliottii , May 2023, Ben Fan and Xiuyu Zhang, NF 150 ( holotype HMAS 352960 View Materials , culture ex-type CGMCC 3.28956 View Materials ) .

Description.

Mycelium composed of hyaline to pale brown, smooth- to verruculose-walled, multi-septate, branched, slender, and uniform hyphae, 1.6–2.8 μm diam. Asexual state: Conidiophores reduced to conidiogenous cells or conidiogenous cells absent, (27.3 –) 37.2–74.6 (– 87.9) × (1.9 –) 2.2–3.0 (– 3.2) μm. Conidiogenous cells arising from the top of the hyphae or branching out from the sides of the hyphae, 0–1 - septate, rough, short, and having few branches, (3.1 –) 3.3–5.6 (– 6.8) × (2.2 –) 2.3–2.8 (– 3.0) μm. Conidia developing directly from the end or side of the hyphae or from conidiogenous cells on conidiophores, oval-shaped to spindle-shaped, in clusters like grapes in bunches, translucent or hyaline, smooth, (2.3 –) 2.7–5.0 (– 6.2) × (1.5 –) 1.6–2.4 (– 3.0) μm. Sexual state unknown.

Culture characteristics.

Colonies on MEA and OA, with a compact surface, dark olive, and irregular edges. The optimal temperature for growth is 20–25 ° C, reaching 5–8 mm in diameter in 10 days. No growth at 5 ° C and 35 ° C.

Additional specimen ( paratype) examined.

CHINA • Jiangsu Province, Nanjing, Nanjing Forestry University, Baima Campus , fungal endophytes from P. elliottii , May 2023, Ben Fan and Xiuyu Zhang, paratype NF 151 .

Notes.

In the phylogenetic analyses of Extremaceae (Fig. 3 View Figure 3 ), the isolate of Botryoconidia globosus clustered with Paradevriesia and Saxophila within the family, although the internal relationships among these genera were not well resolved. NF 150 shows ITS sequence divergence of 9.98 % (45 / 451 bp) from Saxophila ( S. tyrhenica ), supporting its phylogenetic distinctness. Morphologically, B. globosus has small (2.3–6.2 × 1.5–3.0 μm), hyaline, single-celled conidia from reduced conidiophores, while S. tyrhenica produces large (10.0–12.0 × 15.0–20.0 μm), multicellular, brown arthric conidia ( Isola et al. 2016).