Russula boddingii Hembrom, D.Chakr., A.Ghosh & K.Das, 2023

Ghosh, Aniket, Buyck, Bart, Chakraborty, Dyutiparna, Hembrom, Manoj Emanuel, Bera, Ishika & Das, Kanad, 2023, Three new species of genus Russula Pers. from Sal dominated forests of tropical India based on morphotaxonomy and multigene phylogenetic analysis, Cryptogamie, Mycologie 20 (3), pp. 27-50 : 34-38

Russula boddingii Hembrom, D.Chakr., A.Ghosh & K.Das , sp. nov.

( Figs 4-6 )

Russula boddingii Hembrom, D.Chakr., A.Ghosh & K.Das , sp. nov. is mainly separated from R. densifolia Secr. ex Gillet by a combination of medium to large-sized (30-160 mm) pileus, a more intense blackening of the flesh after cutting or bruising, the unequal, the absence of pileocystidia, the stronger reticulation of the spore ornamentation, the more slender hyphal endings (2-6 µm wide) in the pileipellis and its occurrence under dipterocarps in Asia.

HOLOTYPE. — India. West Bengal, Jhargram district, Lalgarh, Karamsol , 22°34’12.9”N, 87°05’25.2”E, alt. 73 m a.s.l., on ground, under Shorea robusta in tropical deciduous forests, 1.VII.2018, M.E. Hembrom, MEH-18-01 (holo-, CAL [ CAL 1860 ]!).

ADDITIONAL SPECIMENS EXAMINED. — India. Jharkhand, Rajmahal hills, Sahibganj district, Mandro block, near Mandro Fossil Park , 25°07’31.3”N, 87°31’22.3”E, alt. 142 m a.s.l., on ground, under Shorea robusta in tropical deciduous forests, 20.VIII.2013, M.E. Hembrom, MEH-13-03; Sahibganj district, Borio block, Pir-Baba Kairasol forest area, 25°09’41.7”N, 87°40’31.9”E, alt. 126 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 24.VIII.2013, M.E. Hembrom, MEH-13-27; Rajmahal hills, Godda district, Boarijore block, Mangra Dahar-Langi and surroundings, 25°01’43.0”N, 87°28’13.8”E, alt. 136 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 01.IX.2013, M.E. Hembrom, MEH-13-31; Rajmahal hills, Pakur district, Hiranpur block, Talpahari to Tugutola forest area, 24°37’02.6”N, 87°40’45.2”E, alt. 94 m. a.s.l., on ground, under S. robusta in tropical deciduous forests, 22.VIII.2014, M.E. Hembrom, MEH-14-28; Pakur district, Litipara block, Sathiya to Sathiyapahar forest area, 24°44’44.3”N, 87°35’03.8”E, alt. 225 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 02.IX.2014, M.E. Hembrom, MEH-14-33; Rajmahal hills, Dumka district, Kathikund block, Kanhaidih reserve forest, 24°19’04.2”N, 87°29’14.3”E, alt. 132 m a.s.l., 18.IX.2015, on ground, under Shorea robusta in tropical deciduous forests, M.E. Hembrom, MEH-15-09; Dumka district, Sikaripara block, Karakata forest area, 24°13’19.0”N, 87°30’16.2”E, alt. 241 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 23.X.2015, M.E. Hembrom, MEH-15-17; Sahibganj district, Taljhari block, Karanpurato village forest toward Gogi , 25°09’02.9”N, 87°43’02.3”E, alt. 61 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 06.XI.2016, M.E. Hembrom, MEH-16-21; Sahibganj district, Borio block, Dhogada-Paharia burial ground forest, 25°02’23.7”N, 87°39’35.8”E, alt. 110 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 08.XI.2016, M.E. Hembrom, MEH-16-32 ( CAL [ CAL 1861 ]); Rajmahal hills, Sahibganj district, Borio block, Dhogada-Paharia burial ground forest, 25°02’23.7”N, 87°39’35.8”E, alt. 110 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 15.XI.2020, M.E. Hembrom, MEH-20-10; Rajmahal hills, Pakur district, Hiranpur block, Talpahari to Tugutola forest area 24°37’02.6”N, 87°40’45.2”E, alt. 94 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 26.VIII.2021, A. Ghosh, AG 21- 08 ( JH); Ranchi district, Getalsud , 23°28’36.5”N, 85°33’23.8”E, alt. 570 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 09.X.2021, M.E. Hembrom, MEH-21-25; Bihar , West Champaran district, Valmiki national Park , Raghia range, Sitalbari enclosure, 27°20’14.4”N, 84°13’05.8”E, alt. 133 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 15.IX.2020, M.E. Hembrom, MEH-20-104; West Bengal , Bankura district, Joypur forest, 23°01’53.00”N, 87°15’15.73”E, alt. 73 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 08.VII.2020, A. Ghosh, AG 20-004; Paschim Medinipur district, Chandra , 22°21’01”N, 87°02’00”E, alt. 90 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 12.VIII.2020, D. Chakraborty, NPDF917 - 17L; Uttar Dinajpur, Kaliyaganj , Dhamja , 25°18’00”N, 88°20’35.9”E, alt. 80 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 07.IX.2020, D. Chakraborty, RGJ-20-08; Uttar Dinajpur, Kaliyaganj , Dhamja , 22°19’44”N, 87°02’39”E, alt. 80 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 13.VIII.2021, A. Ghosh, AG 21-074; Uttar Dinajpur, Kaliyaganj , Dhamja , 25°18’00”N, 88°20’35.09”E, alt. 80 m a.s.l., on ground, under S. robusta in tropical deciduous forests, 10.X.2021, D. Chakraborty, RGJ-21-05.

GENBANK. —OL469097 (nrITS, holotype) andOL469118 (nrITS, specimen voucher no. MEH-16-32); ON365924 (nrLSU, holotype), ON365926 (nrLSU, specimen voucher no. MEH-16-32); ON387513 (mtSSU, holotype), ON387510 (mtSSU, specimen voucher no. MEH-16-32); ON418909 (rpb 2, holotype),ON418910 (rpb 2, specimen voucher no. MEH-16-32).

ETYMOLOGY. — Commemorating Reverend Paul Olaf Bodding, a Norwegian missionary, linguist, folklorist and ethnobotanist who undertook pioneer work on the macrofungi of Rajmahal Hills.

MYCOBANK. — MB 844205.

FACESOFFUNGI NUMBER. — FoF 11436.

DESCRIPTION

Pileus medium-sized to large, 30-160 mm in diam., convex when young, becoming planoconvex to applanate, centrally depressed to umbilicate at maturity; margin smooth, entire when young becoming decurved to plane, sometimes uplifted with age; cuticle smooth, viscid and shiny when wet, dull upon drying, peeling to 1/4 of the radius, greyish white (1B2) to grey (2-5B2) with yellowish white (3A2) tinges. Pileus context firm and up to 9 mm thick at the disc centre, becoming narrower towards margin, chalky white (1-2A1), changing first orange red (8A8) or brownish red (8C6-7), then blackish when cut or bruised; turning dull green (27D3-4) with FeSO 4, and deep to dark turquoise (24E-F7-8) in guaiacol. Lamellae unequal, of different lengths, narrow, up to 5 mm deep, sub-decurrent to decurrent, crowded (15-22/cm at pileus margin), chalky white (1-2A1) to yellowish white (3A2), forked at different distances from the stipe; edges entire and concolorous. Stipe 25-57 × 9-23 mm, cylindrical, subclavate to clavate, central, firm and fleshy; surface dry, smooth, chalky white (1-2A1) to greyish white (1B2); turning dull green (27D3-4) with FeSO 4 and deep to dark turquoise (24E-F7-8) in guaiacol. Stipe context solid, chalky white (1-2A1), changing first orange red (8A8) or brownish red (8C6-7), then blackish when cut or bruised; turning dull green (27D3-4) with FeSO 4 and deep to dark turquoise (24E-F7-8) in guaiacol. Odour insignificant. Taste mild. Spore print not obtained.

Basidiospores globose, subglobose to broadly ellipsoid, (5.8-)6.2-6.7-7.2(-7.8)×(5.5-)5.6-6.0-6.5(-7) µm, Q=(1-)1.07- 1.12-1.16(-1.20); ornamentation composed of relatively dense, obtuse-rounded, conical amyloid warts (up to 0.8 µm high), connected by thick ridges forming an almost complete network; suprahilar spot inamyloid; apiculi up to 1.2 µm long. Basidia (28-)34.5-40-45(-48)× 8-9-10(-11) µm, 4-spored, narrowly clavate to clavate, sterigmata up to 8 µm long; basidiola cylindrical to clavate. Hymenial gloeocystidia on the lamellae sides (22-)33.5-54.5-75.5(-112)×(4-)5-7.5-9.5(-10) µm, emergent up to 14 µm above the other elements of the hymenium, near the lamellae edges usually smaller and narrower, 31-43-55 (-65)×3-5-6(-7) µm, cylindrical to clavate with capitate to moniliform apex; contents completely or partly filled with brown refractive bodies, not reacting in sulfovanillin. Marginal cells absent. Subhymenium layer up to 20 µm thick, pseudoparenchymatous. Hymenophoral trama mainly composed of large nests of sphaerocytes and intermixed with hyphal elements. Pileipellis orthochromatic in Cresyl Blue, sharply delimited from the underlying context, 300-380 µm thick, two-layered; suprapellis 140-200 µm thick, composed of narrow, ascending hyphal terminations; subpellis 160-180 µm deep, composed of more or less dense, horizontally oriented hyphae. Acid-resistant incrustations absent.Hyphal terminations near the pileus margin long, flexuous, densely septate, scarcely branched at the bases, sometimes with lateral branches, thin-walled, partly filled with irregular refractive bodies containing brown pigments; terminal cells (39-)44-58-72(-90)×(3-)4-4.5-5.5(-6) µm, narrowly cylindrical to subulate, apically obtuse-rounded or acute; subterminal cells and the cells below often gradually wider, usually shorter. Hyphal terminations near the pileus centre apically more attenuated; the terminal cells slightly shorter and less wide, measuring (26-)34.5-50-65(-85)×(2-)3-3.5-4.5(-5) µm. Pileocystidia absent.Clamp connections absent from all tissues.

NOTES

In its most recent interpretation, Russula subg. Compactae (Fr.) Bon , emend. Buyck & V. Hofst. ( Hongsanan et al. 2015) includes species that produce more or less thick-fleshed, very small to large basidiomata with dull to dingy white, brown, grey to black pileus, regularly unequal, polydymous lamellae, a mild to very acrid context that is reddening, greying, blackening, rarely browning and often with unpleasant smell, white spore print and spores with inamyloid suprahilar spot; gloeocystidia mostly capitate with one central knob or more frequently with two excentrical knobs. In a recent multilocus phylogeny ( Buyck et al. 2018), this subgenus was shown to be composed of two highly supported lineages: sect. Polyphyllae Buyck & V. Hofst. and sect. Nigricantinae Bataille, which is the core group of this subgenus as it holds the European R. nigricans , the type species. With very few exceptions, species of sect. Nigricantinae have basidiomata that react most frequently by first reddening on bruising before turning to black. This feature, in combination with the unequal, polydymous gills, is still considered to constitute the easiest field character to recognize species of this section ( Das et al. 2020).

A nBLAST of the obtained ITS sequences of our specimens undeniably placed our new species in sect. Nigricantinae with sequences MN075499 (99.51% similarity), MN580113 (99.05% similarity) and JN969389 (99.13% similarity), all three obtained from deciduous dipterocarp forests in Thailand ( Phosri et al. 2012; Pachit et al. 2020; Yuwa-Amornpitak & Yeunyaw 2020), representing earlier reports of R. boddingii Hembrom, D.Chakr., A.Ghosh & K.Das , sp. nov. None of the other sequences resulting from nBLAST was more similar than 96% to our species, and all suggested a placement of our new species in the R. densifolia lineage.

In recent years, several new Asian species have been published in sect. Nigricantinae ( Das et al. 2020; Zhou et al. 2020), but none of these had crowded gills as in the R. densifolia lineage. The latter lineage has been retrieved as a highly supported clade in recent multigene phylogenetic analyses ( Buyck et al. 2018; De Lange et al. 2021). So far, only five described species have been shown to be part of this lineage, but molecularly quite distinct for our new species with very high support ( Fig. 4 ): these species include the European R. densifolia , R. densissima , R. atramentosa and R. fuliginosa , the Australian R. ingwa , as well as at least five additional but undescribed Asian species in this lineage.

Figures

FIG. 4. — Phylogram generated by Maximum Likelihood analysis based on nrITS sequence data of Russula boddingii Hembrom, D.Chakr., A.Ghosh & K.Das, sp. nov. and allied species. Maximum Likelihood bootstrap support values (MLbs) ≥ 70% are shown on the left of “/” and Bayesian Posterior Probabilities (BPP) ≥ 0.95 are shown on the right above or below the branches at nodes. Russula boddingii Hembrom, D.Chakr., A.Ghosh & K.Das, sp. nov. is placed in red font to highlight its phylogenetic position in the tree.

FIG. 5. — Russula boddingii Hembrom, D.Chakr., A.Ghosh & K.Das, sp. nov. (from holotype): A-D, fresh and dissected basidiomata in the field and basecamp; E, F, transverse section through pileipellis showing elements; G, transverse section through lamellae showing hymenial gloeocystidia near the lamellae edges; H, I, transverse section through lamellae showing hymenial gloeocystidia near the lamellae sides; J, transverse section through lamellae showing basidia. Scale bars: A, 40 mm; E, 100 μm; F-J, 10 μm.

FIG. 6. — Russula boddingii Hembrom, D.Chakr., A.Ghosh & K.Das, sp. nov. (from holotype): A, basidiospore; B, hymenial gloeocystidia near the lamellae edges; C, elements of the pileipellis near the pileus centre:hyphal terminations; D, basidia; E, hymenial gloeocystidia near the lamellae sides; F, elements of the pileipellis near the pileus margin: hyphal terminations. Scale bars: 10 µm.