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 Russula tawai
BiostatusPresent in region - Indigenous. Endemic
Images (click to enlarge)
Owner: J.A. Cooper | 
Owner: J.A. Cooper | 
Owner: J.A. Cooper | 
Caption: cap and gill details
Owner: J.A. Cooper | 
Caption: KOH rection on cap and stem
Owner: J.A. Cooper | 
Caption: Top: FeSO4. Bottom: guaiac
Owner: J.A. Cooper | 
Owner: J.A. Cooper | 
Caption: Left: gill with purple edge, ste apex. Right: subcuticle
Owner: J.A. Cooper | 
Caption: Stem. Top: FeSO4, bottom: guaiac
Owner: J.A. Cooper | 
Owner: J.A. Cooper | 
Caption: upper: FeSO4, lower guaiac
Owner: J.A. Cooper | 
Owner: J.A. Cooper | 
Owner: J.A. Cooper | 
Caption: thick walled pleurocystidia
Owner: J.A. Cooper | 
Caption: cheilocystidia
Owner: J.A. Cooper | 
Owner: J.A. Cooper |  | 
Owner: J.A. Cooper | 
Owner: P. Leonard | 
Owner: J.A. Cooper | 
Caption: Stem base left: FeSO4, right: guaiac.
Owner: J.A. Cooper | 
Caption: cap surface and subcuticular vinaceous layer.
Owner: J.A. Cooper | 
Owner: J.A. Cooper | 
Owner: J.A. Cooper | 
Caption: stem apex and gill edge
Owner: J.A. Cooper | 
Caption: stemp base. Right: FeSO4, right: guaiac.
Owner: J.A. Cooper | 
Caption: cap with finely pubescent surface
Owner: J.A. Cooper | 
Caption: Dried type specimen
Owner: Herb PDD | 
Caption: Dried type specimen
Owner: Herb PDD |
Article: McNabb, R.F.R. (1973). Russulaceae of New Zealand. 2. Russula Pers. ex S.F. Gray. New Zealand Journal of Botany 11(4): 673-730 (http://www.rsnz.org/publish/abstracts.php).
Description: pileus: 4.5-7 cm diam., convex when young, centrally
depressed at maturity, slightly viscid under wet conditions, otherwise dry,
finely subpruinose under lens, velar remnants absent, dark magenta to greyish
magenta, or greyish purple, frequently with yellow, greenish yellow, dull olive
green, or dark reddish brown areas; margins entire, thick, non-pectinate. Cuticle
composed of erect, thin-walled, smooth, septate, hair-like hyphae to 100 µm
long, 2.5-4.5 µm diam., without staining contents in KOH, terminal cells unspecialised,
tapering apically, originating from inflated, short-celled hyphae arising from
a layer of sphaerocysts, becoming disorganised with age; pilocystidia absent:
lamellae: adnate, moderately crowded, thin, simple
or forked near stipe, to 12 mm deep, creamy yellow to pallid yellow, not discoloured
at maturity but edges typically tinted with colours of stipe, lamellulae rare
or absent. stipe: 2.5-5 cm long, ± equal or slightly
expanded basally, 1-2.3 cm diam., dry, solid, finely furfuraceous under lens,
pallid greyish magenta or pallid greyish purple, often with rose tints, flesh
often showing through; flesh white, unchanging on exposure to air. Cuticle composed
of interwoven, repent, thin-walled, septate hyphae 2.5-5 µm diam., terminal
cells projecting and aggregated into clumps, caulocystidia absent. spores: spore print not obtained; spores broadly
elliptical to ovate, obliquely apiculate, apiculus to 1.5-(2) µm long. 8.5-10.5
X 7.5-9.5 ornamentation of amyloid or partially inamyloid truncated spines to
l- (1.5) µm high, in small confluent groups, joined basally by fine amyloid
ridges and forming an incomplete reticulum, or occasionally isolated; plage
weakly amyloid, inconspicuous. hymenium:
basidia hyaline, clavate, 42-53 X 10-12 µm, 4-spored, sterigmata
to 7 µm long; pleurocystidia scattered, numerous, fusiform or sub-clavate, hyaline,
thick-walled, walls to 6 µm thick at mid point, thinner at base and apex, contents
refractive in KOH, projecting to 25 µm beyond basidia, apices acuminate, strangulate,
or mucronate, occasionally capitulate, 60-110 X 9-13 µm, cheilocystidia numerous,
filamentous, septate, simple or occasionally sparingly branched apically, to
5 µm diam. hymenophoral trama:
heteromerous, intermixed. context
of pileus: creamy yellow to pallid yellow, unchanging;
structure heteromerous, clamp connections absent. taste: lamellae slowly acrid, context mild. chemical characters: formalin on context—n.r.; phenol on context—
slowly slate grey with purplish or vinaceous tints; FeSO4 on context— rapidly
salmon pink; guaiacol on stipe base—n.r.; KOH on pileus— magenta colour disappears
leaving area orange-red; on context—n.r.; NH4OH on pileus—green; on context—n.r.
Habitat: Solitary or gregarious under Nothofagus.
Notes: The species is characterised by the creamy
yellow lamellae, typically with purplish tinted edges, thin-walled pleurocystidia,
thin-walled filamentous cheilocystidia, and the slowly acrid taste of the lamellae.
The combination of colour reactions to phenol, KOH, and NH4OH is also characteristic.
Russula tawai belongs in section Rigidae and is possibly best assigned to subsection
Amoeninae (Singer 1962).
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