Leucoagaricus changamangaensis Hajra & Niazi, 2023

Khalil, Hajra, Ayyub, Misbah, Akram, Aiza & Niazi, Abdul Rehman, 2023, A new species of Leucoagaricus (Agaricaceae, Basidiomycota) from Changa Manga Forest, Pakistan, Phytotaxa 620 (1), pp. 87-93 : 89-92

Leucoagaricus changamangaensis Hajra & Niazi sp. nov. ( Figures 1 , 2 ).

Mycobank # 849866

Holotype: — PAKISTAN. Punjab: Kasur district, Changa Manga , on humus-rich soil, 192 m a. s. l., gregarious, 02 September 2020, A. R. Niazi & Hajra (CM-14, LAH02920 ). GenBank OP 905641 (ITS).

Etymology: —The specific epithet ‘ changamangaensis refers locality from where the holotype was collected.

Diagnosis: —Is distinguished due to broadly ellipsoid spores with a thin wall; smaller (14– 28 × 5.5–7.5), narrowly clavate cheilocystidia and cylindrical stipe.

Pileus 20–30 mm in diameter, plane, with straight margins at maturity; central disc obtuse, red to reddish brown (10R4/4) in the center; surface squamulose, with radially arranged reddish brown fibrils, becoming sparse and light brown (7.5R5/16) towards margins over a milk white background; context white, fleshy; margins entire, with cracks developing at maturity. Lamellae free, thin, membranous, white to cream (5YR9/2), close with 2–5 tiers of lamellulae, edges entire. Stipe 3.2–4.1 × 0.3–0.5 mm, central, equal to sub-equal, cylindrical, slightly attenuating towards pileus, with a shiny white surface (5YR9/2), and hollow. Annulus present, membranous, white to cream, ascending, superior. Taste and odor not recorded.

Basidiospores [40/7/2], (3.7–) 4.4–7.7 (7.1) × (6.5–) 2.1–5.1 (4.6) µm, 3.9–7.4 × 4.3–4.8, Q = 0.90–0.89, Qav = 0.89, ellipsoid to somewhat ellipsoid, thin-walled, apex with concentric germ pore, amyloid, smooth, guttulate, metachromatic. Basidia 19–34 × 6.5–8.5 µm, clavate, thin-walled, hyaline in KOH, guttulate, smooth, 2–4-spored. Cheilocystidia 14– 28 × 5.5–7.5 µm, narrowly clavate, thin-walled, hyaline in KOH, smooth. Pileipellis hypha 1.2–5.6 µm wide, thin-walled, hyaline to light brown in KOH, unbranched. Stipitipellis hyphae 1.4–7.6 µm wide, cutis made of hyphae, smooth, thin-walled, hyaline, hyphal cell arranged parallel, broadly clavate. Clamp connections absent in all tissues.

Additional Material Examined: — PAKISTAN. Punjab: Kasur district, Changa Manga, Latitude (31.0887) and Longitude (73.962433), 192 m a. s. l., on the ground, decomposed organic matter, under hardwood trees, 15 September 2021, A. R. Niazi & Hajra (CHM-14, LAH#15921 ). GenBank OP 905635 (ITS) .

Figures

FIGURE 1. A–C Basidiomata of Leucoagaricus changamangaensis from Changa manga (Scale bar A = 0.6 cm, B = 0.8 cm & C = 1.5 cm)

FIGURE 2. Microscopic characteristics of Leucoagaricus changamangaensis. A. Basidiospores in Gills, B–E, features in Basidiomata.B. Basidia C. Cystidia, D. Pileipellis, E. Stiptipellis (Scale bars A= 8 µm, B= 9 µm, C = 10 µm, D= 8 µm, E = 12 µm).