Crepidotus asiaticus Guzm.-Dáv., C.K. Pradeep & T.J. Baroni
Pileus 10–52 mm diam, convex with a slight broad umbo when young, becoming plano-convex to applanate with a broad obtuse umbo and finally uplifted in age; deep reddish brown (6D–E7 to 7E7) or “Cuba” (9E8) in buds/buttons and in young ones, velvety; paler with expansion, yellow-ochre (5C6), flesh (6B3), caramel (6C6), brownish orange or bright reddish brick brown (6C7), grayish red (7B4), light brown (7D4–7D6), brick red (7D7), or reddish brown (8E5) at center, and orange-white (5A2), brownish orange (6C5), reddish brown (8D4), or paler elsewhere, or clay color (5C5) in the ground with reddish brown (5D6–5D7) densely matted fibrils (+/− tomentum), tomentose-granulose, minute squamules, or with concolorous appressed squamules throughout, denser at center in mature specimens, dry; margin straight to uplifted, wavy, folded, entire. Lamellae adnate, short decurrent, or with a decurrent tooth, 1.5–3 mm wide, close or crowded with lamellulae of different lengths, yellowish white (4A2) or orange-white (5A2) in young specimens, becoming brownish orange (5C5–5C4) or grayish orange (5B3), orange-white (6A2), light brown (6D4–6D5), or brown (6E5); edge concolorous, entire, even or glistening, fimbriate. Stipe 12–30 × 1–5 mm, central or occasionally slightly eccentric, curved, cylindrical, often compressed, tapering up from a broad base, solid, becoming narrowly hollow; surface creamy white, yellowish white (3A2–4A2), pale yellow (4A3), or grayish orange (5B3), turning brownish on handling, fibrillose striate, upper part pruinose or very minutely erect pubescent overall; base with white strigose hairs and with white mycelial mat. Context white or light yellow (4A4), up to 3 mm thick, soft. Annulus absent. Odor mild, not characteristic. Taste not determined. Spore print brick red (7D7). Basidiospores 5.5–7(–8) × 4–5 μm (Lm = 6.2 ± 0.44, Wm = 4.4 ± 0.28, n/6 = 160), Q = (1.18–)1.25–1.60(–1.75), ellipsoidal to broadly ellipsoidal, amygdaliform, apex obtuse or subacute, with or without hilar depression, without a plage, thick-walled, finely verrucose, warts small, yellowish brown, nondextrinoid. Basidia 15–25(–27.5) × 5.5–7.5 μm, clavate, 4-spored, sterigmata 1–3 μm long, with basal clamp connections. Pleurocystidia absent. Cheilocystidia (14.5–)17–38.5 × (4–)5–9.5 μm, abundant, narrowly utriform, subutriform, utriform, or more or less lageniform, with a short or long narrow neck, apex 4–7 μm diam, obtuse or subcapitate, sometimes branched, clavate or cylindrical, very variable among specimens, thin-walled, hyaline. Subhymenium ramose-inflated. Hymenophoral trama subregular, 1.5–12 μm diam, hyphae thin- to subthick-walled, hyaline to yellowish. Pileus trama radial with interwoven zones to the pileipellis, hyphae, 3–20 μm diam, inflated, thin- to subthick-walled, hyaline to yellowish. Pileipellis a trichoderm with erect to suberect elements as pileocystidia, 15–85 × 7–17.5 μm, clavate, cylindro-clavate, cylindrical, subutriform, oblong, with yellowish brown to reddish brown vacuoles, thin-walled. Stipe trama composed of parallel hyphae, 4–12 μm diam, inflated, thin-walled, hyaline. Stipitipellis composed of parallel hyphae, 4–5.6 μm diam, thin-walled, hyaline. Caulocystidia 19–42.5 × 3.5–13.5 μm, clavate, cylindro-clavate, lageniform, subutriform, rarely flexuous, denser towards upper portion of stipe, grouped in fascicles, thin-walled, hyaline to yellowish. Clamp connections and oleiferous hyphae present.
Habit and habitat: India, solitary, scattered, or in groups on sandy soil under Casuarina or on live
roots, fallen debris-like needles, or fruits of Casuarina litorea (Casuarinaceae). Thailand, scattered under
Castanopsis armata (Fagaceae) and Dipterocarpus sp. (Dipterocarpaceae) and mixed tropical hardwoods on woody fruits, on leaf litter, and soil.
Other specimens examined: INDIA. KERALA STATE: Thiruvananthapuram District, Palode, Jawaharlal Nehru Tropical Botanic Garden & Research Institute (TBGRI) campus, 28 Oct 2005, CKP9401; 27 Jun 2006, CKP9761; 16 Oct 2006, CKP10025; 11 Apr 2007, CKP10166; 12 Apr 2007, CKP10179; 27 Apr 2007, CKP10236; 14 May 2007, CKP10280; 15 May 2007, CKP10285; 15 Oct 2007, CKP10602; 13 Nov 2007, CKP10773; 27 May 2008, CKP10942; 10 Jul 2008, CKP11332; 21 Jul 2008, CKP11466; 3 Nov 2008, CKP12186; 5 May 2009, CKP12439; 11 May 2009, CKP12444; 27 May 2009, CKP12477; 28 May 2009, CKP12482; 29 May 2009, CKP12496; 12 Jun 2009, CKP12589; 26 Aug 2009, CKP12887; 5 Apr 2010, CKP13151; 27 Apr 2010, CKP13184; 10 May 2010, CKP13209; 20 May 2010, CKP13236; 24 May 2010, CKP13256; 31 May 2010, CKP13271; 17 Jun 2010, CKP13313; 20 Oct 2010, CKP13508; 25 Apr 2011, CKP13563; 27 Apr 2011, CKP13578 (all in IBUG). THAILAND. CHIANG MAI PROVINCE: Behind Buddhist Temple, near Mycology Research Center, km 27 Hwy 1095, 8 Jun 2006, Maria Alice Neves & T.J. Baroni TJB 10018 (CORT, duplicates in MFLU, PUL); Doi Inthanon National Forest, km 25 Hwy 1009, 5 Jun 2006, T.J. Baroni & D. Desjardin TJB 9995 (CORT & duplicates MFLU, PUL).
Notes: Crepidotus asiaticus is characterized by a distinctive combination of characters such as medium-sized stipitate basidiome, convex to uplifted brick red to reddish brown squamulose pileus, ellipsoidal to broadly ellipsoidal and amygdaliform nondextrinoid verrucose basidiospores, utriform or lageniform cheilocystidia shape, and presence of pileocystidia and caulocystidia. Until now, this species was observed in India only under a single tree planted in the botanic garden; nevertheless, in Thailand it was found in tropical hardwood stands with Castanopsis and Dipterocarpus species. The species is a saprotroph, and thus eventually it may be found under many different species of angiosperm trees. In addition, because of its stipitate habit, it can colonize substrates embedded in or on soil, such as woody fruits, leaf litter, or roots, unlike the astipitate taxa.
Fig 1. Tree obtained from the maximum-likelihood analysis of the ITS rDNA sequence alignment of Crepidotus species. Two species of Simocybe were used as outgroup. Support values are indicated as follows: posterior probabilities greater than 0.7 and maximum-likelihood bootstrap above branches, maximum-parsimony bootstrap greater than 50% below branches. Stipitate species are marked with an asterisk and the new species in bold.
Fig 2. Basidiomata of Crepidotus asiaticus. A. CKP10280. B. CKP10285. C. TJB 9995. All scale bars = 10 mm.