Cantharellus parvoflavus M. Herrera, Bandala & Montoya, 2021

Montoya, Leticia, Herrera, Mariana, Bandala, Victor M. & Ramos, Antero, 2021, Two new species and a new record of yellow Cantharellus from tropical Quercus forests in eastern Mexico with the proposal of a new name for the replacement of Craterellus confluens, MycoKeys 80, pp. 91-114 : 91

Cantharellus parvoflavus M. Herrera, Bandala & Montoya sp. nov. Figs 2c, d , 4

Holotype.

Mexico. Veracruz: Municipality of Alto Lucero, NE Mesa de Venticuatro, 450-500 m a.s.l. gregarious, on ground, under Quercus oleoides Schltdl. & Cham., 2 Oct 2017, Montoya 5423 (XAL).

Diagnosis.

Differing from other related Cantharellus species (subgenus Parvocantharellus) by the pileus surface with appressed fibrils at center, broadly ellipsoid basidiospores 6-9 (-9.5) × 4.5-5 µm [Q -= 1.52-1.57 (n=3)], pileipellis terminal hyphae (23-) 25-75 (-80) µm × (3.5-) 4-8 µm, mostly cylindrical, often subclaviform, subventricose or somewhat narrowly utriform.

Gene sequences ex-holotype.

nLSUMT371337; tef -1α MT449706.

Etymology.

Referring to a small, yellow chanterelle; from parvus (Lat.): small and Cantharellus flavus (Lat.): yellow

Description.

Pileus 6-26 mm diam, subhemispheric in young, becoming convex to plane convex and centrally depressed, some finally irregularly infundibuliform; margin incurved when young, becoming inflexed to somewhat straight, undulate or irregular or more or less crenate, not or obscurely translucid striate; surface dry, with appressed fibrils at center when young, glabrous at remaining areas, with waxy appearance, bright yellow-orange (5A5-A8) with tiny white to light yellow scales in the center when young, paler at edge when young. Hymenophore decurrent or shortly decurrent, with gill-like folds up to 2 mm deep, subdistant to more frequently distant, at times forked, moderately thick with margin entire or often irregular or eroded, frequently intervenose, some specimens (especially towards the stipe) with irregular low and sinuous veins, often with lower irregular anastomosis among the folds, in some specimens the anastomosis occur practically in the whole hymenophore, while in others only at some areas, especially at pileus margin, with some short lamellulae-like folds, concolorous with the pileus. Stipe (10-) 15-42 × 2-6 mm, broadened towards the apex, somewhat fused, compressed at times or furrowed, solid but soon fistulous to hollow, glabrous, concolorous with pileus. Context fleshy, concolorous with pileus or somewhat paler, with waxy appearance, odor mild, agreeable; taste mild, agreeable.

Basidiospores 6-9 (-9.5) × 4.5-5 µm [X - = 7.6-7.8 × 4.9-5 µm, Q - = 1.52-1.57 (n = 3)], broadly ellipsoid, smooth, thin-walled, hyaline, inamyloid, with granular contents or refractive droplets. Basidia 50-83 (-89) × (6-) 7-10 µm, narrowly clavate to subcylindrical, with 2-5 sterigmata, thin-walled, hyaline; subhymenium composed of cylindrical hyphae 4-6 µm diam. Cystidia absent. Pileipellis composed of intermingled hyphae of 4-7 µm diam, cylindrical, hyaline, yellowish in group, terminal hyphae (23-) 25- 75 (-80) × (3.5-) 4-8 µm, mostly cylindrical, often subclaviform, subventricose or somewhat narrowly utriform, moderately straight to flexuous, inamyloid, thick-walled (<1 µm thick), smooth, hyaline. Pileus trama composed of cylindrical to inflated hyphae, 4-7 µm diam, slightly thick-walled (<1 µm thick), hyaline, some with weakly refringent contents. Hymenophoral trama composed of hyphae 4-5 µm diam, thin-walled, some with weakly refringent contents. Clamp connections present in all tissues.

Habitat.

Solitary to gregarious, rare in the study area, on soil, in tropical oak forest, under Quercus oleoides , September-October, known in the coastal plain of central Veracruz State, east coast of Mexico.

Specimens examined.

Mexico. Veracruz, Municipality of Alto Lucero, NE Mesa de Venticuatro , 392-433 m a.s.l., 27 Sep 2016, Herrera 204; 20 Oct 2017, Herrera 229 (all at XAL) .

Remarks.

The phylogenetic analysis supports (with high values of bootstrap and Bayesian posterior probabilities 100/1) the distinction of Cantharellus parvoflavus as a new species, sister to C. appalachiensis from USA. This latter species, besides their basidiomes being somewhat larger [pileus 10-50 mm/stipe 15-75 × 3-10 (-13) mm], are not distinctly yellow, only dingy yellow, usually dull brown, pale or yellowish-brown at margin, darker to brown on disc ( Petersen and Ryvarden 1971; Bigelow 1978). Moreover, C. appalachiensis has wider broadly-ellipsoid basidiospores [(6.6-) 7.4-8.2 (-8.9) × (4.4-) 4.8-5.6 (-5.9) µm or (6-) 7.5-9 (-10.5) × (4-) 4.5-5.5 (-6) µm] and wider pileipellis hyphae (3-14.5 µm diam. or 9-14 µm diam.) ( Petersen and Ryvarden 1971; Bigelow 1978).

Cantharellus parvoflavus is similar to yellow forms of C. minor , because they have a hygrophoroid appearance, but this latter is usually bright yellow orange to orange, fading to pale orange-buff or pale orange, with glabrous pileus surface, bigger, ellipsoid, slightly phaseoliform basidiospores (6-) 7.5-10 (-11.5) × (4-) 4.5-6 (-6.5) µm and pileipellis terminal elements subcylindrical to subventricose ( Bigelow 1978; Buyck et al. 2010). Cantharellus romagnesianus is close to C. parvoflavus but it develops grey-brown colors in the pileus, its hymenophore has forked veins, often spaced, larger basidiospores [(8-) 9-11.5 (-12.5) × 4-6 (-6.5), Q = 1.71-2.28] and with different shape ( Olariaga et al. 2017).

Figures

Figure 2. Basidiomes of Cantharellus species a, b C. veraecrucis (a Bandala 4505, holotype b Herrera 142) c, d C. parvoflavus (c Montoya 5423, holotype d Herrera 229) e, f C. tabernensis (e Herrera 120 f Herrera 131). Scale bars: 10 mm.

Figure 4. Cantharellus parvoflavus (Montoya 5423, holotype) a basidiospores b Terminal elements of the pileipellis c basidia d longitudinal section of pileipellis. Scale bars: 5 μm (a); 10 μm (b, c); 25 μm (d).