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Page number:450 
Remarks (internal):Pouzarella pamiae is diagnosed by its 3-8 mm broad densely squamulose-hispid pileus with brownish-orange squamules, long (12-25 mm) narrow stipe that bruises dark brown and has a base covered with squamules identical to those on the pileus, thick-walled acuminate to broadly clavate cheilocystidia, and basidiospores averaging 13.1 x 8.6 µm.
Other species with a brownish-orange, densely squamulose-hispid pileus and stipe include P. fulvolanata (Berk. & Broome) Mazzer and P. myoderma (Berk. & Broome) T.J. Baroni (both from Ceylon), P. squamifolia (Murrill) Mazzer from Jamaica, P. sepiaceobasalis (E. Horak) T.J. Baroni from Argentina, and P. ferreri T.J. Baroni et al. from the Dominican Republic, Brazil, and Costa Rica.
Mazzer (1976) described P. fulvolanata with yellowish to tawny colors and basidiospores in the same size range (12-16 x 7-8 µm) as P. pamiae, but it can be differentiated by subpyriform cheilocystidia and larger pileus (13 mm broad) and stipe (32 mm x 2 mm). Noting their similar stature, coloration, and pileus and stipe surfaces, Mazzer (1976) differentiated P. fulvolanata and P. squamifolia based on distribution and stipe color: P. squamifolia, described from Jamaica, has a pallid stipe with ferruginous hairs whereas P. fulvolanata, described from Ceylon, has tawny hairs on the stipe.
The basidiospores, basidia, cheilocystidia, pileipellis, pileocystidia, stipitipellis and caulocystidia of P. pamiae are identical to those described for the Jamaican holotype of P. squamifolia (Mazzer 1976, Baroni et al. 2008). However, P. squamifolia is differentiated by ferruginous colors (tawny in P. pamiae), wider (10 mm broad) pileus, larger (40 x 1.5 mm) stipe, and the absence of a bruising reaction.
Pouzarella sepiaceobasalis is differentiated from P. pamiae by the longer basidiospores (15-19 µm) and longer stipe (60 mm) with a base that gradually becomes blue-black to black (Baroni et al. 2008).
Pouzarella ferreri is separated by a more reddish coloration, longer (?60 mm) stipe, larger (~16.2 x 10.7 µm) basidiospores, globose to sphaeropedunculate cheilocystidia, and black staining reactions (Baroni et al. 2008).
On the basis of type studies, Pegler (1977, 1986) synonymised A. fulvolanatus Berk. & Broome under A. myodermus Berk. & Broome, for which he reported basidiospore measurements of 9-13(-15) x 5.5-7.0 µm (average 10.5 ± 1.0 x 6.5 ± 0.34 µm). He could not verify the presence of cheilocystidia, commenting, "Lamella-edge not revived." Based on further type studies, Horak (1980) synonymised both A. myodermus and A. fulvolanatus under Agaricus lasius, for which he reported basidiospores measuring 10.5-13.5 x 6-8 µm, cheilocystidia absent, and robust basidiomata with ?20 mm broad pilei and 15-50 x 1-3 mm stipes. Therefore, P. pamiae is differentiated from both Pouzaromyces myodermus sensu Pegler (1977) and Pouzaromyces lasius sensu Horak (1980) by larger basidiospores, abundant clavate to acuminate cheilocystidia, and a smaller stature.

Australian taxa related to Pouzarella pamiae
The ML phylogeny weakly (BS <70) supports the clade including P. pamiae and P. farinosa. Both species possess ± thick-walled pigmented napiform to clavate cheilocystidia and versiform pileocystidia. The two species are easily distinguished by basidiospore size (~15.5 x 10.0 µm in P. farinosa) and coloration (orange-gray squamules on a grayish-brown background in P. farinosa).
 
Description type:Original description 
Description:Pouzarella pamiae Largent, sp. nov. Plates 7-8
MycoBank MB 519570
Pileus 3-8 mm broad, 2-4.5 mm high, at first conic to conic-campanulate and densely erect squamulose-hispid over the entire surface expanding to convex and eventually convex-campanulate, remaining erect squamulose hispid on the center but becoming appressed squamulose from the margin first and then to near the center, at first entirely reddish-golden to brownish-orange (6-7C-D5-7) darkening to medium brown (6-7E-F5-6 teak brown to burnt umber) then dark brown (6-7E-F6-7 burnt umber to dark brown), with maturity remaining darker on the disc but lightening to yellowish-white to orangish-white (4-5A2-3), squamule tips lose color and separate showing the whitish-yellow background, not umbonate, opaque, dry and dull; margin decurved and fringed with squamule tips then some eroded as the tips collapse with age. Taste indistinct. Odor indistinct to pungent. Lamellae 3-4 mm long, 1.25-1.5 mm high, pale orange (6A3) then brownish (6E5 sunburn) with basidiospore maturity, narrow and then moderately broad, subdistant to nearly distant; no bruising reaction observed in the margin, fimbriate to serrulate and light-colored when lamellulae are mature. Lamellulae nearly non-existent with at most one lamellula between lamellae. Stipe 12-25 mm long, 0.5 mm broad at the apex, 0.75 mm broad at base, equal to slightly clavate, at first covered by a yellowish-white to orangish-white (4-6A2-3) dense layer of entangled fibrils, with maturity the fibrils darken to colors similar to those of the pileus, at times the consistency and color of the fibrils at the base are identical to those on the pileal surface, eventually the stipe surface becomes slightly roughened as the fibrils collapse onto the surface and then the stipe darkens to medium dark brown (6E6); the surface discolors to dark brown (near 6F6) when bruised; stipe base strigose or matted. Bruising reaction absent.
Basidiospores 7-9-angled, nodulose-angular, subisodiametric to heterodiametric in profile view, 5-6-angled and isodiametric in polar view, 10.0-15.9 (-17.3) x 7.1-11.2 µm (xm = 13.07 ± 1.3 x 8.5 ± 0.8 µm; E = 1.18-1.85; Q = 1.53 ± 0.16; n = 82/2). Basidia 4-sterigmate, clavate, tapered, filled with a droplet, 31.8-48.3 x 11.5-15.3 µm (xm = 42.3 ± 5.6 x 13.6 ± 1.2 µm; E = 2.17-3.78; Q = 3.11 ± 0.4; n = 11/1). Cheilocystidia abundant, broadly clavate to broadly acuminate, with a faint brownish cytoplasmic pigment, ± thick-walled, 47.1-77.6 x 10.1-26.2 µm and located as terminal cells arising from tramal hyphae with at least one subterminal cell inflated. Pleurocystidia absent. Pseudocystidia absent. aborted basidia inconspicuous or rare. Hyphae of the lamellar trama 79.3-240.3 x 5.9-15.3 µm. Pileipellis 111-551 µm deep, an entangled layer of long, rather slender hyphae with cells ± in chains, in young specimens entirely erect and trichodermoid, in older specimens trichodermoid only in the center, semi-erect towards the margin and repent at the margin; distinctly thick-walled in the apical 1-5 cells. Pileocystidia cylindric, cylindro-clavate, broadly clavate, or broadly obclavate, thick-walled and with parietal pigment, 26.0-78.7 x 6.6-13.0 µm (xm = 46.8 x 9.8 µm; E = 2.87-7.52; Q = 4.8; n = 9/1). Hyphae of the pileal trama same size and pigmentation as lamellar trama. Stipitipellis similar to the pileipellis except with the addition of clusters of hymenial elements at the apex; Caulocystidia similar to the pileocystidia, 36.1-79.1 x 8.4-19.9 µm. Pigmentation externally incrusted in the trama, parietal and faintly externally incrusted in the pileipellis and stipitipellis.
Ecology and distribution: scattered in tan-colored soil beneath and protected by an overhanging boulder in a complex mesophyll vine forest on well-drained alluvium (Mossman Gorge National Park) or solitary in hardpacked soil (Danbulla National Park, Lake Euramoo).
 
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