Craterellus albostrigosus C.K. Pradeep & K.B. Vrinda, 2018

Bijeesh, C., Kumar, A. Manoj, Vrinda, K. B. & Pradeep, C. K., 2018, Two new species of Craterellus (Cantharellaceae) from tropical India, Phytotaxa 346 (2), pp. 157-168 : 159-162

Craterellus albostrigosus C.K. Pradeep & K.B. Vrinda sp.nov. Figs.1 , 2

MycoBank MB: 823658

Etymology:— albostrigosus (Latin) , refers to the white strigose hairs of pileus and stipe.

Diagnosis:—Distinguished from similar small Craterellus species by the combination of the grayish brown nonperforate, hygrophanous pileus with white strigose hairs; the strigose solid stipe; smooth grayish hymenophore; 2–5 sterigmate basidia; pileipellis an interrupted epicutis; absence of clamp connections; and unique nrLSU sequence (MG593194).

Holotype:— INDIA. Kerala State: Thiruvananthapuram District, Palode, JNTBGRI campus, 29 August 2016, Bijeesh TBGT16577 ( CAL 1624 !).

Description:— Basidiomata small, thin, 17–33 mm tall, cantharelloid. Pileus 3–19 mm diam., infundibuliform when young becoming convex to plano-convex with a shallow depression at center, umbilicate, not perforate; surface chocolate brown, brownish gray to grayish brown (6F4/8E2/8E3/8F3) when moist, becoming brownish orange to mouse gray (5C3/5D3/5E3) in dry weather or upon loss of moisture, hygrophanous; covered with erect, upright, agglutinated, fibrillose, strigose hairs with pointed to slightly curved tips, white when moist and becoming concolorous with the pileus when dry; margin straight, uneven, wavy, folded, crenulate or rarely incised. Hymenophore continuous over lower side, decurrent, gray (5B1/5B2/6B1), rarely slightly folded near and down to the stipe in some specimens, smooth, forming a demarcating zone with stipe. Stipe 15–35 × 1–3 mm, central, cylindric, compressed in some specimens, rarely ridged, equal, or slightly tapering up from a slightly broad base, rarely forked holding two pilei, solid; surface concolorous with the pileus, covered with erect pointed strigose-fibrillose hairs which is white initially, later becoming concolorous with the surface, dry, solid; basal primordia present in some specimens, 5–7 mm high, filiform with pointed tips covered with white pointed strigose hairs. Pileal context very thin, off white, leathery. Odour mild or none. Taste mild but not distinctive. Spore print off-white.

Basidiospores (8–)9–11.5 × 6–8 μm (Lm =9.8 ± 0.93, Wm =6.97 ± 0.61); Q=1.25–1.66; Qm=1.45, ellipsoid to broadly ellipsoid, smooth, inamyloid, thin-walled, with granular contents, rarely monoguttulate. Basidia 48–72 × 6.5–9 μm, long, narrow, subcylindric, subclavate, flexuous, thick-walled with large guttules or with finely granulose contents; sterigmata 2–3–4–5, 6 μm long, stout, incurved. Basidioles abundant, cylindrical, with finely granulose contents. Hymenial cystidia absent. Hymenophoral trama subregular, hyphae 6–9.5 μm wide, thin-walled, hyaline. Pileal trama composed of interwoven hyphae, 7–9.5 μm wide, thick-walled, hyaline, secondary septations absent. Pileipellis a cutis, interrupted by erect fascicles of hyphae. Pileal hyphae 5–6.5 μm wide, thick-walled, pale yellowish in 3% KOH; the strigose scale cells composed of slightly interwoven fascicles of hyphae with undifferentiated cylindrical terminal cells, 20–39 × 4.5–6.5 μm, thick-walled, hyaline with obtuse apex. Stipitipellis composed of interwoven hyphae, 4–6 μm wide, thick-walled, interrupted with tufts of erect hyphal fascicles; terminal elements 16–33 × 4.5–12 μm, cylindrical, cylindro-clavate to clavate with rounded obtuse apex. Stipe trama composed of interwoven, thick-walled, hyphae 6–7.5 μm wide, hyaline. Clamp connections absent in all tissues.

Habit, habitat & phenology:—Solitary to scattered on mud wall and on earthworm mounts in tropical evergreen forest, near Hopea parviflora ( Dipterocarpaceae ), June–November.

Additional specimens examined:— INDIA. Kerala State, Thiruvananthapuram District, Palode , JNTBGRI campus, 25 July 2016, Bijeesh TBGT16450 ; ibid, 26 July 2016, Bijeesh TBGT16455 ; ibid, 27 July 2016, Bijeesh TBGT16461 ; ibid, 28 July 2016, Bijeesh TBGT16466 ; ibid, 26 August 2016, Bijeesh TBGT16567 ; ibid, 30 June 2017, Bijeesh TBGT16871 ; ibid, 18 August 2017, Bijeesh TBGT17038 ; ibid, 9 September 2017 Bijeesh TBGT17077 ; ibid, 13 September 2017 Bijeesh TBGT17090 ; ibid, 27 October 2017 Bijeesh TBGT17192 ; ibid, 2 November 2017 Bijeesh TBGT17232 .

Comments:—Owing to its brownish gray to grayish brown cantharelloid basidiomata, Craterellus albostrigosus should be compared with a number of similarly colored species, viz., Craterellus strigosus T.W. Henkel, Aime & A.W. Wilson (2012: 1472) , C. atratoides T.W. Henkel, Aime & A.W. Wilson (2012: 1470) , C. atratus (Corner) Yomyart, Watling, Phosri, Piapukiew & Sihanonth (2012: 1474) , C. subundulatus (Peck) Peck (1978: 720) and C. calyculus (Berk. & Curt.) Burt. (1978: 721) . Craterellus strigosus , described originally from Guyana ( Wilson et al. 2012), resembles C. albostrigosus in most of the macro and microscopic features. However, the neotropical species differs from C. albostrigosus by having smaller basidiomata with a dark brown non-hygrophanous pileus, grayish to brownish hymenophore, slightly smaller, broadly ellipsoid basidiospores (8–10 × 5.9–8(8.5) μm), presence of clamp connections, occurrence on humus and bark of living Dicymbe corymbosa and also as an EcM symbiont of D. corymbosa , D. altsonii and Aldina insignis ( Fabaceae ). A BLASTn search reveals that Craterellus strigosus (JQ915120) shows only 93% sequence identity (860/925) with the present material.

Craterellus atratoides is similar in overall features with C. albostrigosus but is distinct by its grayish brown perforate, glabrous pileus and stipe, decurrent bluish gray hymenophore, larger ellipsoid spores (10.8–12(13) × 7.1–9 μm), presence of abundant clamp connections and habitat in Dicymbe forest. Craterellus atratus is similar to the present species in having small gray centrally stipitate pileate basidiomata, a grayish smooth hymenophore, a solid stipe with strigose scales, subellipsoid similarly-sized basidiospores, presence of filiform-acuminate primordia, and the habitat is the same. In spite of these similarities, C. atratus is quite distinct due to its campanulate to broadly campanulate, dark brown pileus with less prominent scales, presence of abundant clamp connections and an ectotrophic association with Dicymbe plants. Furthermore, our collection is phylogenetically distinct ( Fig. 5 ).

Based on a megablast search with the nrLSU (963bp) sequence of C. albostrigosus , the closest hit revealed was an unnamed Craterellus species from China, Craterellus sp. (KM484695) with 96% sequence identity. Further information about this species, however, is unavailable for comparison. Some of the comparable Indian species include C. parvogriseus , C. shoreae , Craterellus indicus and Craterellus mussooriensis D.A. Reid, K.S. Thind & Adlakha (1958: 132) Craterellus parvogriseus can be distinguished by the gray to brownish gray glabrous pileus with uplifted margin; grayish yellow hollow glabrous stipe; white to grayish white hymenophore with irregular folds and slightly larger basidiospores (7–9.6–12 × 6.5–7.6–9 μm). Craterellus shoreae can be separated on account of its vivid yellow to orange yellow basidiomata, deeply depressed to infundibuliform, radially appressed fibrillose pileus; pale orange to greenish white hymenophore; tomentose hollow stipe; 4-sterigmate basidia and larger basidiospores (8.0–10.4–13.0 × 5.6–7.2–9 μm). Craterellus indicus , a recently described species from India is similar in overall stature, spore size, and absence of clamp connections. In spite of these similarities, C. indicus is quite distinct in its light brown to sand colored, infundibuliform, nonhygrophanous pileus, cream-colored hymenophore, yellowish gray, glabrous, hollow stipe, 2–4 sterigmate basidia, pileipellis embedded in a gelatinous matrix and gregarious to caespitose habit in Cedrus deodara forest. Craterellus mussooriensis differs clearly from the present species by the light brown glabrous pileus and stipe; excentric to lateral stipe, cream radially ridged hymenophore and 4-sterigmate basidia. Craterellus indicus (HM113529) and C. parvogriseus (MF421098) shares 95% and C. shoreae (KY290585) shares 94% sequence similarity with C. albostrigosus . The ML and Bayesian trees shared a similar topology where C. albostrigosus is placed close to Craterellus sp. KM484695.

Figures

FIGURE 1. Craterellus albostrigosus. A–C. basidiomata in situ. D–E. basidiomata showing hymenophore and filiform primordia. Scale bar=10 mm. Photos: C. Bijeesh

FIGURE 2. Craterellus albostrigosus. A–B. basidia. C. spores. D. pileipellis E. pileal fasciculate scale cells. F–G. fasciculate scale elements of stipitipellis. Scale bar=10 μm. Photos: C. Bijeesh

FIGURE 5. Phylogenetic analysis of Craterellus species inferred from nrLSU sequences. Bootstrap values (ML, ˃50%) and Bayesian posterior probabilities (BI, ˃0.90) are shown above/below branches.Values to the right and left of the ‘/’ are ML-BS and BI-PP respectively. GenBank accession numbers are given after the taxonomic names.