Asterophora parasitica ( Persoon 1801: 371 : Fr.) Singer (1951: 171)

Reschke, Kai, Lotz-Winter, Hermine, Fischer, Christian W., Hofmann, Tina A. & Piepenbring, Meike, 2021, New and interesting species of Agaricomycetes from Panama, Phytotaxa 529 (1), pp. 1-26 : 14-16

Asterophora parasitica ( Persoon 1801: 371: Fr.) Singer (1951: 171) , Fig. 13a

Description: —Basidiocarps collybioid, fasciculate, arising from a dense mycelial layer adhering to the host. Pileus 0.5–1.0 cm diam., convex, conico-campanulate to plane with inrolled margin, when mature sometimes slightly concave, surface finely whitish fibrillose when young, sometimes with few yellowish spots (3A4–4A4), when mature with reddish brown (8D5) or greyish brown (7D3) tinges. Trama white to reddish brown. Lamellae adnate to decurrent, up to 2.0 mm broad, distant, thick, fleshy at base, often somewhat irregular to deformed, anastomosing, initially white, later reddish brown (8E4) or greyish brown (7E4), with smooth, waxy, blunt and even margin, in old basidiocarps minutely floccose. Stipe 0.4–3.0 × 0.2–0.4 cm, central, subcylindrical, slightly attenuated upwards, often curved, sometimes distorted, fibrous, hollow in mature specimens, surface finely whitish fibrillose, subtomentose to felty towards the base, with few yellowish spots when young (3A4–4A4) and greyish brown tinges (7D3, 7E3) when mature. Basal mycelium cottony, white. Odour indistinct to strongly farinaceous, taste not tested.

Basidiospores 4.0–6.0 × 2.5–4.0 µm (n = 10 spores of 3 specimens), broadly ellipsoid to ellipsoid, hyaline, thinwalled, inamyloid. Hymenium not well developed, basidia present only near and at lamellar edge in young basidiocarps. Basidia 15–35 × 5.0–6.0 µm, clavate to subclavate, mostly 4-, some 1- or 2-spored. Lamellar trama composed of narrow, parallel hyphae of 3.0–5.0 µm diam., gelatinized. Chlamydospores formed within the lamellar trama, mostly at hyphal ends, few intercalary, 22–25–29 × 9.5–9.9–11.0 µm, Q = 2.15–2.49–2.95 (n = 21), amygdaloid to fusiform, smooth, blunt, brownish ochraceous, with hyaline tip, thick-walled, with 0.5 µm thick outer wall and 6.0–10.0 µm thick inner wall. Pileipellis a cutis composed of slightly interwoven, slightly thick-walled, smooth hyphae, some with brown, intracellular pigment. Stipe surface composed of parallel hyphae, 5–30 µm diam., hyaline, undulating, smooth, constricted at septa, and with slightly thickened wall, gelatinized, sometimes with intracellular pigment. Clamp connections abundant in all parts of the basidiocarp and the mycelium.

Habitat: —Parasitic and fruiting on basidiocarps of species of Russulaceae . In montane forests with Alnus acuminata and Quercus spp. in Chiriquí Province, Panama.

Notes: — Asterophora parasitica is widely distributed in the northern hemisphere ( Singer 1986). In the southern hemisphere it was reported from New Guinea ( Horak 1980). Its occurrence is already known from Colombia ( Guzmán & Varela 1978) and Costa Rica ( Halling & Mueller 2002), the neighbouring countries of Panama. Parasitising obligate ectomycorrhizal species, it is restricted to habitats with ectomycorrhizal host plants. In Panama, A. parasitica was found in montane Quercus -dominated forest in elevations between 1800 and 2500 m a.s.l. The ITS sequences of the specimens from Panama have p-distances of 0.5 to 1.6% compared to sequences of A. parasitica specimens in GenBank, increasing with geographic distance. A study with wider scope might reveal distinct populations. However, no morphological differences were observed between specimens from Panama and Germany.

Specimens examined: — GERMANY. Baden-Württemberg: Hornberg, Storenwald, mixed coniferous and deciduous forest, on rotting basidiocarps of Russula sp. , sect. Compactae , 415 m a.s.l., N4 8 °12’30.0’’ E 8°13’43.3’’, 17 Oct 2013, H. Lotz-Winter HLW 3601 (M-0312073)!; PANAMA. Chiriquí Province: Volcán, near Paso Ancho, PNVB, mountain path to the summit, montane cloud forest dominated by Quercus spp. and Alnus acuminata , on rotting basidiocarps of Russula sp. , sect. Compactae, 2200 m a.s.l., N 08°48’55.9’’ W 82°34’17.5’’, 04 July 2015, H. Lotz-Winter, T. Hofmann, O. Koukol, P. Zehnalek PAN180 (UCH9076, M-0312070)!; Cerro Punta, Bajo Grande, PNVB, Sendero Los Quetzales close to Mirador Alto Respingo, on rotting mushroom basidiocarps, 2500 m a.s.l., N 8°50’46.5” W 82° 31’49.1’’, 20 July 2015, H. Lotz-Winter, R.V. Villareal, S. Cáceres, J. Rodríguez PAN346 (UCH8975, M-0312071)!; Volcán, near Paso Ancho, PNVB, mountain path to the summit, montane forest with abundant Quercus spp. and Comarostaphylis arbutoides , on rotting basidiocarps of Russula sp. , sect. Compactae, 2000 m a.s.l., N 08°48’56.0’’ W 82°34’44.5’’, 28 June 2017, K. Reschke, T. Hofmann KaiR694 (UCH9246, M-0312072)!.