Entoloma luteobrunneum Karstedt & Capelari

Karstedt, Fernanda, Bergemann, Sarah E., Gates, Genevieve, Ratkowsky, David, Cunha, Kelmer Martins & Capelari, Marina, 2024, Species of Entoloma (Entolomataceae) with cuboidal basidiospores from Brazil, Phytotaxa 654 (1), pp. 1-76 : 42-46

publication ID	https://doi.org/ 10.11646/phytotaxa.654.1.1
DOI	https://doi.org/10.5281/zenodo.13215022
persistent identifier	https://treatment.plazi.org/id/19575B62-7639-0C42-FF4A-8C7ABD62A7D6
treatment provided by	Felipe
scientific name	Entoloma luteobrunneum Karstedt & Capelari
status	sp. nov.

Treatment

Entoloma luteobrunneum Karstedt & Capelari , sp. nov.

Figs. 18 View FIGURE 18 , 27a–d View FIGURE 27 , 34c View FIGURE 34

MB 838593

Etymology:— Luteobrunneum refers to the yellow pileus covered by brown fibrils.

Diagnosis:— Entoloma luteobrunneum is characterized by a convex yellow pileus covered with brownish adpressed fibrils, and concolorous stipe.

Type:— BRAZIL. Rio De Janeiro: Teresópolis, Serra dos Órgãos National Park , Postcard Trail , 5 January 2011, F. Karstedt et al. FK1693 (Holotype, SP) .

Description:— Pileus 23 mm diam., conical, not translucent-striate or only so near the margin, yellow and after collection becoming brownish to dark brown, slightly hygrophanous, surface adpressed-fibrillose to slightly adpressed-fibrillose at the involute and slightly irregular margin. Pileus context not observed. Lamellae adnexed or almost free, scarcely ventricose (<2 mm at deepest part), yellow, crowded with three tiers of lamellulae, margins concolorous with faces, entire or slightly irregular. Stipe 65 × 3–5 mm, slightly attenuated upwards, circular in cross-section, centrally attached, yellow with whitish base, glabrous, longitudinally adpressed-fibrillose, hollow, with white basal tomentum. Odor and taste indistinct. Spore print not observed.

Basidiospores cuboidal with an obvious hilar appendix, excluding the projections 8.7–10 × 8.7–11.2 µm [xm = 9.4 (± 0.64) × 9.88 (± 0.78) µm, Q = 1–1.28, Qm = 1.12 (± 0.1), n = 21], diagonally 10–12.5 × 11.2–12.5 µm [xm = 11.29 (± 0.7) × 11.96 (± 0.63) µm, Q = 1–1.25, Qm = 1.06 (± 0.07), n = 21], thin-walled. Basidia clavate, 37–57 × 11.2–16 µm (n = 20), hyaline, thin-walled, 2- or 4-sterigmate. Cheilocystidia clavate or cylindro-clavate, sometimes fusoid-ventricose, 45–95 × 10–16 µm (n = 20), hyaline or straw yellow, thin-walled. Pleurocystidia absent. Pseudocystidia hyphoid, cylindrical or fusiform, sometimes branched, not exceeding the margin of the hymenium, 2.5–5 µm diam. (n = 20), hyaline or straw yellow, refractive in ammonia solution, thin-walled. Lamellar trama composed of parallel, cylindrical, broadly cylindrical or narrowly fusoid hyphae, 5–17 µm diam. (n = 20), hyaline, thin-walled; sub-hymenium branched. Pileitrama composed of radially arranged, cylindrical or inflated hyphae, 2.5–31 µm diam. (n = 24), hyaline, thin-walled. Pileipellis a cutis of prostrate hyphae, rarely forming slightly tangled groups, cylindrical, 3.7–16 µm diam. (n = 20), hyaline or with straw yellow intracellular pigment, thin-walled; terminal hyphae cylindrical with a rounded apex or, sometimes, cylindro-clavate, 46–215 × 10–13(–15) µm diam. (n = 21), hyaline or with straw yellow intracellular pigment, thin-walled. Stipitipellis a cutis of prostrate hyphae, 2.5–10 µm diam. (n = 20), cylindrical, with straw yellow intracellular pigment, thin-walled. Caulocystidia absent. Clamp connections present. Refractive hyphae present.

Habitat:—Solitary, in soil, in the Atlantic Forest biome.

Distribution:—To date collected only in Rio de Janeiro, Brazil, the type locality.

Comments:— Entoloma luteobrunneum is nearest to E. capes , as both are of similar color; however, they differ as E. luteobrunneum has a conical apex to the pileus and the presence of pseudocystidia, whereas E. capes has a convex pileus and pseudocystidia are absent.

Entoloma luteolamellatum (Largent & Aime) Blanco-Dios, Tarrelos View in CoL 17: 35. 2015. [≡ Trichopilus luteolamellatus Largent & Aime, Mycologia View in CoL 102: 644. 2010].

Figs. 19 View FIGURE 19 , 33e–g View FIGURE 33

Description:— Pileus 21–40 mm diam., initially conical, conical-convex or campanulate and then flattened, margin involute, entire and sometimes undulate, umbo present, becoming less pronounced with age, surface strongly fibrillose-squamulose or fibrillose-velutinous, with short, very small scales, not translucent-striate, brown, not hygrophanous. Pileus context yellow. Lamellae adnate, adnate-sinuate or sinuate, faces smooth, ventricose (<4 mm at deepest part), pale yellow, yellow or cream, crowded with two tiers of lamellulae, margins irregular. Stipe 30–80 × 3–7 mm, cylindrical or attenuated upwards, centrally attached, pale yellow with brownish fibrils, surface slightly striate, fibrous or slightly adpressed-fibrillose, hollow, with or without some white basal tomentum. Stipe context yellowish or orange. Odor indistinct. Taste sweet. Spore print not observed.

Basidiospores cuboidal, 4-angled in profile view, diagonally 6.2–7.5 × 7.5–8.7(–10) µm [xm = 7.7 (± 0.58) × 7.3 (± 0.4) µm, Q = 1–1.2, Qm = 1.05 (± 0.08), n = 51/4] and 7.5–10 × 8.7–10 µm [xm = 8.83 (± 0, 44) × 8.64 (± 0.43) µm, Q = 1–1.33, Qm = 1.02 (± 0.07), n = 51/4], thin-walled. Basidia clavate, 31–48 × (10–)11.2–14 µm (n = 25/3), hyaline, thin-walled, 2–4-sterigmate. Cheilocystidia abundant, along the entire lamella margin, cylindrical or clavate, mostly cylindro-clavate, or flexuous and sometimes slightly capitate, often branched, sometimes septate, 31–106 × 5–11.2 µm (n = 61/4), hyaline or slightly yellowish brown, thin-walled. Pleurocystidia and pseudocystidia absent. Lamellar trama composed of parallel, cylindrical or broadly cylindrical hyphae, 5–19(–30) µm diam. (n = 64/4), hyaline or slightly straw yellow, thin-walled, septa distant (reaching 1250 µm in length, n = 1); sub-hymenium not observed. Pileitrama composed of radially-arranged hyphae, 8.7–29 µm diam. (n = 24/2), cylindrical, cylindrical-tortuose or irregular, hyaline or with straw yellow intracellular pigment, thin-walled, septa distant. Pileipellis a cutis of prostrate cylindrical hyphae, 5–13.7 µm diam. (n = 30/2), with brown or straw yellow intracellular pigment, in transition to a trichoderm formed by groups of anticlinal terminal hyphae; anticlinal hyphae cylindrical or cylindro-clavate, sometimes cylindrical with an subcapitate or irregular apex, with or without septa, 50–150(–300) × 6.2–16(–19) µm (n = 49/3), with brown or straw yellow intracellular pigment, the pigment often dissolved, but sometimes coagulated, thin-walled. Stipitipellis a cutis, partly in transition to a trichoderm, forming caulocystidia, prostrate hyphae cylindrical, 6.2–12.5 µm diam. (n = 17), with straw yellow or brown intracellular pigment, sometimes with incrustations, thin-walled, septate. Caulocystidia cylindrical or clavate, 27–49 × 6.2–12.5 µm (n = 4), with straw yellow or brown intracellular pigment, thin-walled. Clamp connections present. Refractive hyphae present.

Habitat:—Solitary or dispersed, in the Amazon Forest biome.

Distribution:— Entoloma luteolamellatum was originally described from Guyana ( Aime et al. 2010) and is now reported from Pará, Brazil.

Additional material examined:— BRAZIL. Pará: Caxiuanã, Caxiuanã National Forest, Ferreira Penha Station , 13 February 2011, R . Maziero & M. Tassilo 11RMT094 ( MG); R . Maziero & M. Tassilo 11RMT097 ( MG); R . Maziero & M. Tassilo 11RMT109 ( MG); Plot 1, 15 February 2011, F. Karstedt et al. FK1866 (SP) .

Comments:— Entoloma luteolamellatum is easily recognized by the conical umbonate pileus, with the brown fibrillose-velutinous surface and yellow lamellae, the cuboidal basidiospores, cylindrical cheilocystidia, and the almost trichodermal pileipellis. Collections from Pará did not show significant morphological or molecular variations ( Fig. 3 View FIGURE 3 ) when compared to the holotype of Aime et al. (2010) .

The subgenus Trichopilus has morphological characteristics into which the analyzed material fits, being recognized by the robust habit, strong pigmentation, generally concolorous stipe and pileus, in addition to the radially arranged, obviously scaly silky fibrils (Romagnesi & Gilles 1979, Largent 1994, Karstedt et al. 2019). However, in our phylogenetic analysis, E. luteolamellatum is not placed in Entoloma subg. Trichopilus and is closely related to other species with cuboidal basidiospores.