Collybiopsis subpolygramma J. Q. Yan, L. Ding, & S. N. Wang, 2025

Ding, Ling, Zhong, Ben-Jian, Zeng, Hui, Wang, Sheng-Nan & Yan, Jun-Qing, 2025, Four new species of Collybiopsis (Omphalotaceae, Agaricales) from subtropical regions of China, MycoKeys 118, pp. 289-311 : 289-311

Collybiopsis subpolygramma J. Q. Yan, L. Ding, & S. N. Wang sp. nov.

Fig. 2

Etymology.

Referring to its similarity to C. polygramma, that pileus is sulcate.

Holotype.

China • Zhejiang Province, Lishui City, Qingtian County, Lanni Lake , 1 August 2021, Jun-Qing Yan, Bin-Rong Ke and Zhi-Heng Zeng, HFJAU 2658 .

Diagnosis.

This species is characterized by its pileal surface, white in color with a light brown center; crowded and occasionally forked lamellae; white to black-brown stipe; slender cylindrical cheilocystidia; basidia mainly 2 - spored; and absence of pleurocystidia.

Macrostructures.

Pileus 32–61 mm in diam., convex to plane, becoming uplifted in age, umbonate at disc, surface smooth, sulcate up to center from the margin, light brown (7 D 5–6) at the center, gradually becoming lighter towards the margin, margin white. Lamellae adnexed, occasionally forked, crowded, with 1– 3 types of lamellulae, white. Stipe 49–68 × 2.4–4.2 mm, central, hollow, cylindrical, equal, white to black-brown (8 F 5), surface covered with white fibrils, base covered with white mycelium.

Microstructures.

Basidiospores in side view [n = 115] (5.9) 6.4–8.1 (8.7) × (3.7) 4.1–5.1 (5.2) µm (av = 7.2 × 4.6 µm, Q = 1.4–1.8 (2.0) (Qm = 1.6 ± 0.1), ellipsoid to elongated-ellipsoid, in profile slightly curved or flattened on one side; in face view (3.7) 4.0–5.0 (5.1) µm broad, ellipsoid to elongated-ellipsoid, thin-walled, hyaline, non-amyloid. Basidia 24–34 × 5.6–7.9 µm, clavate, 2 - spored, occasionally 4 - spored. Pleurocystidia absent. Cheilocystidia 21–50 × 5.9–8.6 µm, abundant, slender cylindrical, occasionally fusiform, apex obtuse, occasionally mucronate or capitate, sometimes with small tubercles, thin-walled, hyaline. Pileipellis a cutis, hyphal cells 2.9–9.9 µm broad. Stipitipellis a cutis, hyphal cells 4.0–9.7 µm broad, thin-walled. Caulocystidia 29–100 × 5.1–8.4 µm, abundant, slender cylindrical, apex obtuse or capitate, thin-walled. Clamp connections present.

Habitat.

Scattered or gregarious on the ground in mixed broad-leaved forests.

Distribution.

China.

Additional specimens examined.

China • Fujian Province: Wuyishan City, Daliankeng , 6 June 2022, Jun-Qing Yan and Lin-Gen Chen, HFJAU 3551 ; Zhejiang Province: Lishui City, Qingtian County, Lanni Lake , 1 August 2021, Jun-Qing Yan, Bin-Rong Ke and Zhi-Heng Zeng, HFJAU 2644 ; Qingtian , 31 August 2021, Ya-Ping Hu, HFJAU 3277 .

Remarks.

Collybiopsis subpolygramma is morphologically similar to G. coracicolor (Berk. & M. A. Curtis) J. L. Mata , G. hondurensis (Murrill) J. L. Mata , C. neotropica (Singer) R. H. Petersen and C. polygramma , all of which have a cutis of pileipellis without rameales-type structure, similarly shaped basidiospores, and the absence of pleurocystidia. However, G. coracicolor has smaller pileus (shorter than 25 mm), larger cheilocystidia (70 × 8–10 µm), and brown incrustation on the pileipellis hyphae ( Dennis 1951). Gymnopus hondurensis has four-spored basidia and clavate cheilocystidia ( Mata and Ovrebo 2009). Collybiopsis neotropica has smaller pileus (shorter than 23 mm), larger basidiospores (8.2–9.7 × 4.3–4.8 µm), larger basidia (29–32 × 6.8–9.7 µm) with four spores, and irregular, filamentous cheilocystidia ( Singer 1961). Collybiopsis polygramma has smaller pileus (shorter than 25 mm) with a distinct umbilicate, absence of cheilocystidia, and hyphae of stipe are thick-walled, up to 3 µm ( Mata and Petersen 2003).

Additionally, G. lodgeae (Singer) J. L. Mata also has a cutis of pileipellis without rameales-type structure and similarly shaped basidiospores. However, G. lodgeae has a smaller pileus (shorter than 20 mm), larger cheilocystidia (32–56 × 10–14 µm), and the presence of pleurocystidia ( Mata and Petersen 2003).

Figures

Figure 2. Collybiopsis subpolygramma. A – C. Basidiomata; D – F. Basidiospores; G. Basidia; H – J. Cheilocystidia; K. Pileipellis; L. Caulocystidia. All microscopic structures were observed in 5 % KOH, and 1 % Congo red was used as the stain. Scale bars: 30 mm (A – C); 5 µm (D – F); 20 µm (G); 30 µm (H – I); 20 µm (J); 30 µm (K, L).