Russula coronata Manz & F. Hampe, 2025

Manz, Cathrin, Amalfi, Mario, Buyck, Bart, Hampe, Felix, Yorou, Nourou S., Adamčík, Slavomír & Piepenbring, Meike, 2025, Just the tip of the iceberg: uncovering a hyperdiverse clade of African Russula (Basidiomycota, Russulales, Russulaceae) species with signs of evolutionary habitat adaptations, IMA Fungus 16, pp. e 140321-e 140321 : e140321-

publication ID

https://doi.org/10.3897/imafungus.16.140321

DOI

https://doi.org/10.5281/zenodo.15801711

persistent identifier

https://treatment.plazi.org/id/85115E41-2F4D-510F-808A-0366766FF7CB

treatment provided by

by Pensoft

scientific name

Russula coronata Manz & F. Hampe
status

sp. nov.

Russula coronata Manz & F. Hampe , sp. nov.

Figs 15 View Figure 15 , 16 View Figure 16 , 17 View Figure 17

Diagnosis.

Pileus surface violet-grey with fugitive jagged white remnants of a partial veil at the margin, taste mild, spore print white, marginal cells near lamella edges with finger-like projections and pileocystidia staining slightly violet-grey in sulphovanillin, occurring in gallery forests. Differs from Russula annulata R. Heim by white-coloured lamellae edges.

Holotype.

Benin. Donga, Bassila , co-ord. 9°0.1'N, 1°38.9'E, alt. 360 m, in a gallery forest, under Berlinia grandiflora , on sandy soil, 30. 06. 2022, leg. C. Manz, F. Hampe, S. Sarawi, A. Rühl & R. Dramani, CM-22-241 (holotype B 70 0105420 , isotype UNIPAR). GoogleMaps

Additional material examined.

Benin. Donga, Bassila , co-ord. 9°0.1'N, 1°38.9'E, alt. 360 m, in a gallery forest, under B. grandiflora on sandy soil, 02. 07. 2022, leg. C. Manz, F. Hampe, S. Sarawi, A. Rühl & R. Dramani, CM-22-261 (paratype, B 70 0105421 , UNIPAR) GoogleMaps .

Description.

Growth habit: basidiomata solitary or in groups of two. Pileus: medium-sized, 60–65 mm in diam., plane, slightly centrally depressed; margin even, distinctly striate up to 1 / 3 to ½ of the pileus radius, regularly shaped, sometimes slightly undulate, finely crenulate, when young, covered by a crown of fugitive, jagged, white partial veil remnants; cuticle smooth, matt, finely pruinose, not peelable, colour near the margin purplish-grey (13 B 2) or greyish-magenta (13 B 3, 14 D 3– 4,14E 3–4), near the centre greyish-magenta (13 C 3) or dark purple (14 F 3–4), sometimes with light milk-white (1 B 2) spots. Lamellae: 6–7 mm wide, 5–6 lamellae present along 1 cm near the pileus margin, narrowly adnate or emarginate, white, occasionally furcated near the stipe attachment, anastomoses and lamellulae absent; edges entire, concolourous. Stipe: 55–60 × 11–13 mm, cylindrical, sometimes narrowing towards the base, slightly bulging here and there; smooth to slightly rugose, annulus absent, white with a greyish-magenta (14 E 3) hue near the base; hollow to slightly cottony stuffed. Context: approx. 0.5 mm thick at half pileus radius, white, unchanging when bruised, brittle, taste mild, odour inconspicuous; macrochemical reactions: guaiac after 8–10 seconds negative on stipe and positive (++) on lamellae surfaces, FeSO 4 weak salmon orange, sulphovanillin negative, KOH negative, phenol negative. Spore print: white (Ia).

Spores: (7.3 –) 7.9–8.4 – 8.8 (– 9.4) × (6.9 –) 7.6–8.1 – 8.5 (– 9.2) µm (n = 60), Q = (1 –) 1.01–1.04 – 1.06 (– 1.09), globose to subglobose; ornamentation of large, distant, amyloid spines [(1 –) 2–3 (( – 4) in a circle of 3 µm diam.], 1.7–2.6 µm high, connected by numerous lines [(1 –) 2–4 (– 5) in the circle] forming a complete reticulum, isolated elements absent, spines and line connections with frequent secondary warts visible only by SEM; suprahilar plage small, inamyloid, without ornamentation. Basidia: (34 –) 37.5–43.5 – 49.5 (– 59) × (12.5 –) 14–15 – 16 (– 17) µm (n = 40), clavate to broadly clavate, 4 - spored; basidiola approx. 8–9 µm wide, clavate to subclavate. Hymenial cystidia: on lamellae sides (86 –) 93.5–99.5 – 106 (– 112) × (10 –) 12–14.5 – 16.5 (– 22) µm (n = 40), fusiform, originating in subhymenium and somewhat protruding over basidia, thin-walled, apically obtuse, with a 2–15 µm long appendage; heteromorphous contents amorphous, located in the upper half, not reacting to sulphovanillin. Hymenial cystidia near the lamellae edges shorter and narrower, (43 –) 54.5–65 – 75.5 (– 89.5) × (8 –) 9–11 – 12.5 (– 14) µm (n = 40), cylindrical or fusiform, sometimes slightly centrally constricted, with one or two 1–8 µm long terminal knobs; heteromorphous contents less dense, sometimes located only in the upper half. Lamellae edges: fertile, marginal cells intermixed with basidia and basidiola. Marginal cells: (19 –) 23–27 – 31.5 (– 36) × (4 –) 5–6.5 – 8.5 (– 10.5) (n = 40), variably shaped, coarsely diverticulate with several finger-like, irregular projections, optically empty, thin-walled. Pileipellis: orthochromatic in Cresyl blue, gradually passing to the underlying context, 170–300 µm deep; suprapellis a trichoderm, 25–45 µm deep, composed of erect hyphal terminations embedded in a gelatinous matrix; gradually passing to a 170–270 µm deep subpellis of loosely interwoven, irregularly orientated, strongly gelatinised, 2.5–3 µm wide hyphae, becoming denser and horizontally arranged near the context. Acid resistant incrustations absent. Hyphal terminations: near the pileus margin composed of 1–3 unbranched cells, thin-walled, terminal cells (13 –) 23.5–29.5 – 35.5 (– 44) × (3 –) 3.5–5 – 6 (– 7) µm (n = 60), predominantly subulate, rarely cylindrical, apically obtuse; subterminal cells distinctly shorter, 4–9 µm wide, ellipsoid or cylindrical. Hyphal terminations near the pileus centre of 2–4 (– 5) unbranched cells, thin-walled; terminal cells (9 –) 13–19.5 – 25.5 (– 36) × (2.5 –) 3.5–4 – 4.5 (– 6.5) µm (n = 60), subulate or cylindrical; subterminal cells 3–6 µm wide, mostly cylindrical, becoming barrel-shaped close to the subpellis. Pileocystidia: near the pileus margin (19.5 –) 23–30 – 37 (– 49.5) × (4 –) 4.5–5.5 – 6.5 (– 7) µm (n = 40), one-celled, usually lanceolate, sometimes subcylindrical, originating in the suprapellis or in upper part of the subpellis, thin-walled, apically obtuse, with a 4–7 µm long appendage or terminal knob; heteromorphous contents amorphous, turning slightly to violet-grey in sulphovanillin. Pileocystidia near the pileus centre similar in size, shape and heteromorphous contents to pileocystidia near the pileus margin, (18 –) 21.5–27 – 32.5 (– 44) × 3.5–4.5 – 5.5 (– 7) µm (n = 40). Context: without cystidioid hyphae, oleiferous hyphae frequent.

Etymology.

corona = crown, referring to the jagged velar patches on the pileus margin.

Distribution and ecology.

Only known from the Bassila gallery forest in Benin.

Notes.

Both collections of R. coronata showed serrated fragments of a partial veil on the pileus margin, for which we introduce the term “ crown ”. The presence of a partial veil is frequent in tropical African Russula species. In several species, the veil is very fugacious and remnants can be observed either as a ring attached to the stipe or the pileus margin or as a crown on the pileus margin or lost due to weather impacts. This feature should, therefore, be treated with caution when identifying R. coronata . Russula annulata is a violet-grey capped species described from Madagascar with an annulus or crown ( Heim 1937). It shares the reticulate spore ornamentation and the trichodermal pileipellis with shorter ellipsoid to subglobose subterminal cells, but differs by a stipe entirely covered by vivid violet pustules, lamellae with a dark violet edge and violet-coloured context under the pileipellis ( Heim 1937, 1938). The type specimen of R. annulata is lost ( Buyck 1994) and, after reviewing the original description, we assume that it is based on a mixture of similar species due to the considerable morphological variations described by Heim. Therefore, the macromorphological comparison is based on the original aquarelle painting of the type specimen ( Heim 1937). Russula annulatosquamosa Beeli and Russula annulatolutea Beeli are other annulate species which differ by olive yellow pileus colours and acrid taste ( Beeli 1936). Russula acriannulata Buyck is an annulate species with ochre-brown pileus colours which shares the trichodermal pileipellis structure with single-celled pileocystidia, but differs by spores ornamented by isolated warts ( Härkönen et al. 1993). Russula annulatobadia Beeli is an annulate species with wine-red pileus colours which shares the reticulate spore ornamentation, but differs by the absence of pileocystidia and the presence of filiform marginal cells ( Buyck 1994). Russula acuminata Buyck is a species without remnants of a partial veil and with wine-red pileus colours which shares similar marginal cells and spores, but differs by strongly ramified hyphal terminations in the pileipellis ( Buyck 1994).