Xerophorus pakistanicus M. Asif, Saba & M. Raza

Asif, Muhammad, Saba, Malka & Raza, Mubashar, 2023, First report of the genus Xerophorus from Asia with the description of Xerophorus pakistanicus (Callistosporiaceae), a new species from Southern Punjab, Pakistan, Phytotaxa 632 (1), pp. 38-48 : 41-46

Xerophorus pakistanicus M. Asif, Saba & M. Raza , sp. nov. ( Figs. 2 , 3 )

MycoBank: MB849110

Fungi of Pakistan No. (FOP_5009)

Etymology:—The specific epithet “ pakistanicus ” refers to the country in which the type specimen was collected.

Diagnosis:— Xerophorus pakistanicus differs from X. olivascens due to its brown to dull orange, parabolic to campanulate pileus, stipe turning yellowish brown on handling, amygdaliform to oblong basidiospores, welldifferentiated narrowly cylindrical to utriform cheilocystidia, pileipellis hyphae with clavate terminal cells, utriform to pyriform caulocystidia and presence of clamp connections only in the stipitipellis.

Holotype:— PAKISTAN. Punjab, Pirowal Irrigated Forest, District Khanewal , 30°34′34″ N, 71°98′48″ E, 136 m elev., on nutrient-rich soil, 28 July 2022, SP-64, Muhammad Asif ( LAH37886 ). GenBank accessions: ITS = OQ947795; 28 S = OQ947829 .

Description:— Pileus 0.8–1.3 cm diam., convex or parabolic to campanulate, brown (7.5YR4/4) at center, becoming dull orange (7.5Y7/4) towards margin, moderately depressed at center, dry and dull, tomentose or matted woolly, or fibrillose, margin straight and entire, rarely splitting at maturity, context thin. Lamellae pale yellow (2.5YR8/4), adnexed to sinuate, narrow to broad, margins entire rarely eroded, concolorous with faces, moderately crowded, 2 tiers of lamellulae. Stipe 1.4–2.8 × 0.3–0.5 cm, pale yellow (2.5YR8/4) near the cap becoming light brown (7.5YR6/3) towards the base, centrally attached, slightly bent or curved from middle, surface reticulate near the cap, becoming longitudinally striate towards the base, becoming light yellowish brown (2.5Y6/4) on handling, cylindrical, hollow, dry and shiny near the cap becoming dull towards the base, slightly bulbous base, solid interior. Annulus and Volva absent.

Basidiospores [50/2/2], (4.8–) 5.3–6.6 (–7.2) × (3.2–) 4–4.6 (–5.2) µm, avl × avw = 6 × 4.3 μm, Q = 1.1–1.8, Qav = 1.4, amygdaliform, rarely oblong, thin-walled, smooth, apiculus present or sometimes absent, hyaline in 5 % KOH, inamyloid, congophilous, mono-guttulate with greenish internal content. Basidia (26.7–) 26.9–31.8 (–36.1) × (5.8–) 6.1–7.5 (–8.3) µm, avl × avw = 29.3 × 6.8 µm, clavate, bi-sporic, thin-walled, hyaline in 5 % KOH, greenish oil droplets present, congophilous. Cheilocystidia (16–) 17.7–21.4 (–24.5) × (2.9–) 3.3–4.4 (–5.2) µm, avl × avw = 19.7 × 3.9 µm, narrowly cylindrical to flexuose, sometimes narrowly clavate or utriform, sometimes constricted at middle, short cells at the base, thin-walled, no internal content observed. Pleurocystidia absent. Pileipellis a trichoderm of erect hyphae, 2.2–5.1 μm in diam., avw = 3.2 μm, irregularly arranged, cylindrical and hollow, terminal cells rarely modified into clavate elements, thin-walled, septate, rarely constricted at septa, smooth, rarely branched. Pileocystidia absent. Stipitipellis a cutis, made up of long and cylindrical hyphae 2.3–6.8 μm diam., avw = 3.5 μm., rounded terminal cells or rarely modified into clavate elements, thick-walled, septate, rarely constricted at septa, regularly arranged, clamp connections present, rarely branched. Caulocystidia (15.4–) 18.7–24.9 (–30.5) × (6.1–) 6.6–10.8 (–14.7) µm, avl × avw = 7.6 × 2.9 µm, utriform to pyriform or clavate, hyaline, thin-walled. Clamp connections present only in stipitipellis.

Habit and habitat:—Collybioid, saprotrophic, mostly in pairs, rarely solitary on nutrient-rich loamy soil under Dalbergia sissoo .

Geographical distribution:—So far, known only from the type locality, District Khanewal, Punjab, Pakistan.

Additional specimen examined:— PAKISTAN. Punjab, Pirowal Irrigated Forest, District Khanewal , 30°34′34″ N, 71°98′48″ E, 136 m elev., on nutrient-rich soil, 30 July 2022, SP-77, Muhammad Asif, GenBank accessions: ITS = OQ947796 ; 28 S = OQ947830 .

Figures

FIGURE 2. a–d Basidiomata of Xerophorus pakistanicus (Holotype; LAH37886); e Habitat. Photos by: Muhammad Asif

FIGURE 3. a–g Line drawings of Xerophorus pakistanicus (Holotype; LAH37886) a = Basidia, b = Basidiospores, c–d = Cheilocystidia, e = Pileipellis, f = Stipitipellis, g = Caulocystidia. Scale bars: a–d = 5 µm; e–g = 3 µm. Drawings by: Muhammad Asif.