Lactarius aurantiobrunneus X.H. Wang, 2019

Wang, Xiang-Hua, Das, Kanad, Bera, Ishika, Chen, Yu-Hui, Bhatt, Rajendra Prasad, Ghosh, Aniket, Hembrom, Manoj Emanuel, Hofstetter, Valérie, Parihar, Arvind, Vizzini, Alfredo, Xu, Tai-Min & Zhao, Chang-Lin, 2019, Fungal Biodiversity Profiles 81 - 90, Cryptogamie, Mycologie 20 (5), pp. 57-95 : 69-72

83. Lactarius aurantiobrunneus X.H. Wang , sp. nov.

( Figs 9 ; 10A ; 11 )

Differs from L. hirtipes , L. alpinihirtipes and L. fulvihirtipes in the spores with high ornamentation not forming a reticulum, and from L. furfuraceus in the less furfuraceous pileus and less reticulate spores.

TYPUS. — China. Guizhou Prov., Leishan Co., Leigong Mt. nature reserve, 26°23’05.4’’N, 108°11’38.9’’E, 1850 m a.s.l., under Quercus engeriana , 23.VI.2017, coll. X.H. Wang, no. 4234 ( KUN [ HKAS 101912 ]!).

MYCOBANK. — MB 829369.

GENBANK. — MK351921 - MK351925 (ITS).

ETYMOLOGY. — Aurantio- = orange, -brunneus = brown, referring to the orange brown fruiting bodies.

ADDITIONAL SPECIMENS EXAMINED. — China. Guizhou Prov.:Suiyang Co., Kuankuoshui, near tea farm, 1500 m a.s.l., 23.VI.1988, coll. P.G. Liu, no. 48 (KUN[HKAS 20560]); Suiyang Co., Kuankuoshui nature reserve, 1500 m a.s.l., 24.VII.2010, coll. X.H. Wang, no. 2399 (KUN[HKAS 61365]); Leishan Co., Leigong Mt. nature reserve, 26°23’2’’N, 108°11’35’’E, 1800 m a.s.l., 24.VI.2017, coll. X.H. Wang, no. 4256 (KUN[HKAS 101913]). — Yunnan Prov., Xinping Co., Ailao Mts. nature reserve, road from Gasa to Zhenyuan, 23°56’07’’N, 101°27’49’’E, 2090 m a.s.l., 13.VIII.2017, coll. X.H. Wang, no. 4543 (KUN[HKAS 104224]), no. 4544 (KUN[HKAS 104225]).

HABIT, HABITAT AND DISTRIBUTION. — 1-3 individuals together, in fagaceous forests. Southwestern China (Yunnan and Guizhou Provinces).

DESCRIPTION

Basidiomata

Small to medium-sized, slender.

Pileus

20-35 mm in diam., at first convex with a pointed papilla, becoming plano-convex with a depressed center when mature; surface dry, hygrophanous, ± strongly rugose, occasionally concentrically cracked, transparently sulcate to sulcate when wet and fully mature, margin often crenulate, reddish brown when young, light brown to reddish brown when mature.

Context

0.5-1 mm thick, paler than or nearly concolorous with lamellae.

Lamellae

2.5-3 mm broad, decurrent, medium spaced, grayish orange when young, brownish orange to light brown or concolorous with the pileus when mature.

Stipe

40-80 × 3-5 mm, cylindrical, equal or gradually enlarged toward base, hollow; surface dry, nearly smooth, concolorous with the pileus; base often strigose with reddish brown hairs.

Latex

Watery or cream-watery, neither discoloring nor staining.

Odor

None.

Spore print

Not obtained.

Basidiospores

(140/7/6) 7.0-7.8-8.5 (10.5) × (6.0) 6.5-7.0-8.0 (8.5) Μm [Q = (1.00) 1.04-1.19 (1.26), Q = 1.12 ± 0.05] [holotype (40/2/1): 7.0-7.8-8.5 (9.0) × 6.5-6.9-7.5 (8.0) Μm, Q = (1.00) 1.07-1.19 (1.22), Q = 1.12 ± 0.05], subglobose, broadly ellipsoid, rarely ellipsoid; ornamentation 1.0-2.0 Μm high, of broad ridges and subtransparent wings, connecting into closed meshes, not forming a reticulum, free ends of ridges and isolated warts common; plage not, distally or totally amyloid.

Basidia

4-spored, 32-55 × 10-15 Μm, clavate, subfusiform.

Pleuromacrocystidia

Common to numerous, mostly emergent, (25) 45-83 × (6) 8-14 Μm, fusiform, sublanceolate, some with a moniliform apex, with strongly refractive granular or agglomerated contents, projecting up to 40 Μm beyond the basidia layer, originating from trama, subhymenium or at the same depth as the basidia.

Hymenophoral pseudocystidia

Scattered to common, 3-4 Μm broad, some gradually enlarged toward apex, with refractive contents.

Lamella edge

Sterile; marginal cells 7-20 × 4-10 Μm, similar to basidioles in shape, clavate, cylindrical; cheilomacrocystidia absent.

Pileipellis

An epithelium, locally with hyphoid extremities, 30-60 Μm thick, with yellowish brown pigmentation; terminal cells of suprapellis 10-25 × 6-15 Μm, ellipsoid, short cylindrical, globose; cells of subpellis 10-30 Μm in diam., globose, ellipsoid, rarely pyriform; hyphae beneath pileipellis 5-15 Μm broad.

Stipitipellis

A cutis, of closely packed, predominantly longitudinally arranged hyphae, with pale yellowish brown pigmentation; hyphae 3-12 Μm broad, often inflated to ventricose, yellowish brown, slightly to medium thick-walled (0.5-1.0 Μm).

Lactifers

Scattered, colorless.

Pileus and stipe trama

Lacking rosettes.

NOTES

One more species of the L. hirtipes species complex. Lactarius aurantiobrunneus X.H. Wang , sp. nov., is more orange than L. hirtipes J.Z. Ying and L. alpinihirtipes X.H. Wang but less yellow than L. fulvihirtipes X.H. Wang. The color approaches L. furfuraceus X.H. Wang. The spore dimension is intermediate between L. hirtipes and L. alpinihirtipes-L. fulvihirtipes - L. furfuraceus ( Wang & Liu 2002; Wang 2017, 2018; Wang et al. 2018a). The spore ornamentation is never as reticulate as the other four relatives. In the field it was easily confused with L. hirtipes or L. furfuraceus although the medium distant lamellae and nearly smooth pileus slightly deviate from those two species respectively. Lactarius aurantiobrunneus X.H. Wang , sp. nov., is less common than L. hirtipes and often found in well-preserved natural habitats.

Figures

FIG. 9. — Original tree generated by Neighbor-Joining (NJ) phylogenetic analysis, rooted with midpoint. NJ analysis was conducted in MEGA X, using bootstrap method (1000 replicates),p-distance as substitution model,transitions and transversions both included,uniform rates among sites,homogeneous pattern among lineages and pairwise deletion for gaps treatment. The bootstrap proportions higher than 70% are indicated above the nodes. New species are in bold. Sample labels are provided in the order of species name, GenBank accession, and geographical origin. For new species, sample numbers with initials of collectors are provided after GenBank accessions.

FIG. 10. — Basidiocarps:A, Lactarius aurantiobrunneus X.H.Wang,sp.nov.(HKAS 101912,holotype);B, L.exilis X.H.Wang,sp.nov.(HKAS 90043);C, L. collybioides X.H. Wang,sp. nov.(HKAS 76002, holotype);D, L. flaviaquosus X.H. Wang,sp. nov.(HKAS 104207,holotype); E, L. resinosus X.H. Wang,sp. nov.(HKAS 104241).

FIG. 11. — Lactarius aurantiobrunneus X.H. Wang, sp. nov. (HKAS 101912, holotype): A, basidiospores; B, pleuromacrocystidia; C, lamella edge; D, pileipellis. Scale bars: A, 5 μm; B, 20 μm; C, D, 25 μm.