Marasmius margallensis F. Razzaq & Khalid, 2023

Razzaq, Fauzia & Khalid, Abdul Nasir, 2023, Marasmius margallensis, a new species of Marasmius sect. Sicci from Margalla Hills, Pakistan, Phytotaxa 589 (1), pp. 15-26 : 18-22

Marasmius margallensis F. Razzaq & Khalid sp. nov.

Mycobank no:—MB847558

Figs. 3–5

Holotype:— PAKISTAN, Islamabad, Margalla Hills , 1604m a.s.l., gregarious on twigs of deciduous trees and dead leaves of Margalla Hills, August 2019, Abdul Nasir Khalid, SIM35, Holotype, ( LAH37597 ) (GenBank: OP804130 , OP804203 ) .

Diagnosis:—It is characterized by hemispherical pileus when young, subumbonate, pale yellow to dull orange, grayish red from the center, light gray towards margins; clavate to narrowly fusiform basidiospores and relatively short pleurocystidia.

Etymology:—‘ margallensis ’ (L.) refers to Margalla Hill, Islamabad, Pakistan, the location from where type specimen was collected.

Description:— Basidiomata 3–8 cm in height, gregarious, fragile. Pileus 1–2 cm in diam., campanulate, hemispheric to broadly parabolic when young, subumbonate, pale yellow (2.5Y8/3), dull orange (7.5YR7/4), grayish red (2.5YR6/2) from the center, light gray (7.5Y8/2) towards margins, dull, dry, glabrous surface, rugulose, thin, margins sulcate to striate. Lamellae free, emerginate, distant to subdistant, L= 20–25, l= 1–2, broad, thin, whitish to pale yellow (7.5Y8/3), margins even, lamellulae present. Stipe 2–7 × 0.1–0.3 cm, central, equal, cylindrical, minutely purinose, shiny, dull reddish brown (7.5R5/3) at upper side, dark reddish gray (7.5R4/1) towards base, with basal mycelial pad. Taste and Odor not recorded.

Basidiospores (10.4–) 10.9–13.5 (–15.1) × (3.0–) 3.1–4.5 (–4.7) µm, avl × avw= 12.4×3.6 µm, Q= 2.3–4.5 µm, Qav= 3.5 µm, clavate to narrowly fusiform, slightly curved, apiculate, smooth, guttulate, thin-walled, hyaline in % KOH. Basidia (27.6–) 28.6–37.5 (37.8) × (5.3–) 5.6–6.9 (–6.9) µm, avl × avw= 32.49×6.31 µm, narrowly clavate, with 2-4 long sterigmata, guttulate, thin-walled, hyaline in 5% KOH. Cheilocystidia (13–) 13.3–18 (–18.6) × (5.4–) 5.5–7.2 (–7.8) µm, avl×avw= 16.20×6.44 µm, in form of broom cells of the Siccus - type, clavate, sub-cylindrical to pyriform, projections digitate, obtuse and subacute, thin-walled, hyaline in 5% KOH. Pleurocystidia (24.4–) 27.9–34.4 (–35.5) × (4.7–) 5.0–7 (–7.2) µm, avl×avw= 31.61×5.82 µm, cylindrical, narrowly fusoid, fusiform, thin-walled, hyaline in 5% KOH. Pileipellis hymeniderm, consists of Siccus - type thick-walled broom cells, digitate, acute, (13.3–) 13.4–19.7 (–22.5) × (4.8–) 5.3–6.5 (–7.3) µm, avl-avw= 16.14×5.83 µm, pale brownish yellow in 5% KOH, pileus trama 6.0– 8.26 µm in diam., avw=7.64 µm, smooth, thin-walled, branched, septate, hyaline clamp-connection present, hyphae hyaline in 5% KOH. Stipitipellis a cutis, cylindrical, hyphae 3.51–11.46 µm in diam., avw=7.48 µm, parallel, septate, clamp-connection present, thick-walled, brown or dark brown with olivaceous walls in 5% KOH.

Chemical reactions: Basidiospores and hymenium non-dextrinoid and inamyloid, while Pileipellis, trama hyphae and stipitipellis dextrinoid.

Ecology and Distribution:—Saprotrophic and gregarious on tree branches and fallen leaves in Margalla Hills, Punjab, Pakistan.

Additional specimen examined:— PAKISTAN. Islamabad, Margalla Hills National Park , found gregarious in Margalla Hills, temperate, monsoonic climate, at 1604 m a.s.l., September, 2019, Abdul Nasir Khalid, SIM34 ( LAH37596 ), GenBank ( OP804131 ) .

Figures

FIGURE 3: Marasmius margallensis (SIM35, Holotype). A–D: Basidiocarps in their natural habitat.

FIGURE 4: Microscopic features of Marasmius margallensis A-G: A. Hymenium, B. Basidia, C. Pleurocystidia, D. Cheilocystidia, E. Basidiospores, F. Pileipellis Siccus-type broom cells, G. Stiptipellis.

FIGURE 5: Line drawings of Marasmius margallensis. A–E: A. Basidia, B. Basidiospores, C. Cheilocystidia, D. Pleurocystidia, E. Pileipellis Siccus-type broom cells.