Russula callainomarginis J. F. Liang & J. Song
Creators: name: Xie, Xiu-Chao
name: Buyck, Bart
name: Song, Yu
Publisher: name: Zenodo
Year: 2023
Subjects: Biodiversity
Taxonomy
Fungi
Basidiomycota
Agaricomycetes
Russulales
Russulaceae
Russula
Russula callainomarginis

description: Russula callainomarginis J.F.Liang & J.Song
Figs 9–10
Material examined
CHINA • Guangdong Province, Zhaoqing City, Dinghushan Biosphere Reserve, on the ground in evergreen broad-leaf forest mainly with Fagaceae trees; 10 Jun. 2018; Y. Song K18061013; GenBank nos: MN275693 (ITS), MN839582 (nLSU), MN839632 (mtSSU), MT085535 (rpb1), MT085659 (rpb2), MT085602 (tef1); GDGM79715 • same data as for preceding; 22 Apr. 2019; Y. Song K19042220; GenBank no: MN839555 (ITS); GDGM79716.
Description
Basidiomata medium to large sized. Pileus 6–10 cm in diam., hemispherical to convex when young, turning applanate with depressed center to infundibuliform; surface glabrous, dry, viscid when wet, white to cream (#FFFAFA, #FFFFF0) with reddish brown (#F5DEB3, #F2E0B7) tint; margin slightly undulate and upward. Lamellae adnate to decurrent, unequal with multidymous lamellulae, often forked near stipe and pileus margin, interveined, white at first, turning cream with brown tint (#FEEABA, #FAEDB3) with maturity; edge entire, concolorous. Stipe central, subcylindrical, solid at first, turning hollow with age, 4–6 cm long, white, stained with reddish brown (#F9E197, #F2D782) when old, longitudinally rugulose. Context white. Odor distinct. Spore print whitish.
Basidiospores subglobose to ellipsoid, rarely globose, (40/2/2) (5.4–)5.7–6.3–7.1(–7.4) × (4.9–)5.2– 5.6–6.1(–6.5) µm, [Q = (1.03–)1.04–1.16–1.24(–1.36)], hyaline in 5% KOH; ornamentation amyloid, composed of verrucous to cylindrical warts less than 1 µm in height, some fused into short crests, mostly connected by fine lines forming partial reticulum; suprahilar spot amyloid. Basidia (25–)27– 29.5–32(–34) × 8–9.5–11(–12) µm, clavate, 2- or 4-spored, thin-walled; sterigmata 4–10.5 × 0.8– 1.6 µm. Pleurocystidia (23–)27–43–81(–101) × 5–7.5–10.5 µm, mostly typical fusiform, with obtuse, mucronate or papillate apices, thin-walled, with refractive contents mostly distributed in middle to upper parts, some subcylindrical, arising from deep in subhymenium, weakly positive in SV. Cheilocystidia (23.5–)26–33–39(–41.5) × (5.5–)6.5–7.5–10 µm, fusiform, with obtuse or mucronate apices, thinwalled, with refractive contents mostly at medium parts. Subhymenium pseudoparenchymatous. Lamellar trama composed of numerous sphaerocytes surrounded by connective hyphae, sphaerocytes measuring 10–28 × 7.5–23 µm. Pileipellis composed of ascending to erect hyphae, 100–140 µm thick; hyphae cylindrical, septate, hyaline, thin-walled, 1.5–5 µm wide; terminal cells (8–)10.5–19–35 × 2.5– 3.5–5.5 µm, cylindrical, rarely lageniform, with obtuse apices, hyaline, some incrusted. Pileocystidia (11–)26–55.5–80(–84) × 2–4–6(–7) µm, cylindrical to fusiform, with obtuse, mucronate to papillate apices, with granular refractive contents, unchanging in SV. Stipitipellis composed of cylindrical, septate hyphae measuring 1.5–4 µm wide; terminal cells cylindrical with obtuse apices, hyaline. Caulocystidia (16.5–)30–54–68(–74) × 1.5–4–6.5 µm, cylindrical, obtuse or papillate, with refractive contents. Clamp connections absent in all tissues.
Comments
Russula callainomarginis was recently described from China (Song et al. 2022). Collections of this species from DHSBR are mostly in accordance with the original morphological descriptions, except that DHSBR specimens have obviously smaller basidia [(25–)27–29.5–32(–34) × 8–9.5–11(–12) µm] and pileocystidia unchanging in SV (turning dark grey to blackish when first described).
description: Published as part of Xie, Xiu-Chao, Buyck, Bart & Song, Yu, 2023, Species of Russula subgenera Archaeae, Compactae and Brevipedum (Russulaceae, Basidiomycota) from Dinghushan Biosphere Reserve, pp. 28-63 in European Journal of Taxonomy 864 on pages 49-52, DOI: 10.5852/ejt.2023.864.2085, http://zenodo.org/record/7785576