Entoloma dragorufescens

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 : 36-40

E ntoloma dragorufescens Karstedt & Capelari , sp. nov.

Figs. 14 , 17d–f , 37b–c

MB 838599

Etymology:— Drago refers to the spores being like those of E. dragonosporum , and rufescens refers to the reddish color of the basidiome.

Diagnosis:— Entoloma dragorufescens is characterized by the combination of a red-brown basidioma with a conical, strongly translucent-striate pileus often with a well-developed pointed umbo, pale lamellae relative to the pileus, cuboidal basidiospores with elongated angles that sometimes resemble a star, in addition to cylindrical and clavate cheilocystidia and a pileipellis as a cutis of prostrate, entangled hyphae in transition to a trichoderm.

Type:— BRAZIL. Santa Catarina: São Paulo, Itapoá, Volta Velha Private Natural Heritage Reserve , Casa de Vidro Trail , 10 December 2012, F. Karstedt et al. FK2102 (Holotype, FLOR) .

Description:— Pileus 5–16 mm diam., 6–18 mm tall, conical with conical apex or with an elongated pronounced papilla, brownish red, burgundy, margin often paler, strongly translucent-striate, hygrophanous, surface glabrous or slightly adpressed-fibrillose, margin of pileus smooth, becoming dentate with age; concolorous with the pileus, translucent. Pileus context thin. Lamellae adnexed, adnexed-sinuate or sinuate, faces smooth, narrow (<1.5 mm deep) to slightly ventricose, pale red-brown, tending to pinkish, close with three tiers of lamellulae, margins entire or irregular and slightly paler than the faces. Stipe 30–75 × 1–3 mm, cylindrical or attenuated upwards, centrally attached, light brown-red, light orange-red or dark orange, glabrous, slightly adpressed-fibrillose, hollow, with white basal tomentum. Stipe context red-brown, translucent. Odor indistinct. Taste not observed. Spore print not observed.

Basidiospores cuboidal with elongated angles, sometimes resembling a star with 4–6 projections, 4-angled in profile, excluding the projections, 6.2–7.5(–8.7) × 7.5–8.7 µm [xm = 7.39 (± 0.34) × 7.79 (± 0.47) µm, Q = 1–1.2, Qm = 1.05 (± 0.08), n = 50/4], including the projections, 8–10.5(–12.5) × (8–)8.7–11.2(–12.5) µm [xm = 9.25 (± 0.84) × 9.93 (± 0.86) µm, Q = 1–1.28, Qm = 1.07 (± 0.07), n = 50/4] and diagonally 10–12.5(–14) × 11–13.7(–15) µm [xm = 11.77 (± 0.7) × 12.14 (± 0.82) µm, Q = 1–1.12, Qm = 1.03 (0.04), n = 50/4], thin-walled. Basidia clavate, 34–51 × 10– 15 µm (n = 31/4), hyaline, thin-walled, 4-sterigmate. Cheilocystidia of the ‘serrulatum-type’ abundant, along the entire lamellar margin, cylindro-clavate, clavate or clavate-tortuose, 40–70 × 8.7–15 µm (n = 37/4), hyaline, thin-walled. Pleurocystidia and pseudocystidia absent. Lamellar trama composed of parallel, cylindrical or sometimes inflated hyphae, 3.7–20(–30) µm diam. (n = 71/4), hyaline, thin-walled; sub-hymenium branched. Pileitrama composed of radially arranged hyphae, 5–21(–25) µm diam. (n = 60/4), cylindrical, broadly cylindrical or irregular, hyaline or, sometimes, with a little straw yellow intracellular pigment, thin-walled. Pileipellis a cutis of slightly entangled and prostrate cylindrical hyphae, in transition to a trichoderm, 5–10(–13.7) µm diam. (n = 57/4), hyaline or with a little straw yellow intracellular pigment, sometimes with straw yellow incrusted pigment, thin-walled; terminal hyphae undifferentiated, cylindrical, broadly cylindrical, cylindro-clavate, apex rounded or sometimes fusoid, 47–131 × 6.2–13.7 µm (n = 30/4). Stipitipellis a cutis, hyphae cylindrical, 3.7–12.5 µm diam. (n = 30/2), hyaline, thin-walled. Caulocystidia cylindro-clavate or clavate, 40–77 × 3.7–12.5 µm (n = 6/2), hyaline or with a little straw yellow incrusted pigment, walls thin or slightly thickened. Clamp connections present in all tissues. Refractive hyphae present in the trama of the lamellae and the pileus.

Habitat:—Gregarious or scattered, in litter with sand, in restinga forest of the Atlantic Forest biome.

Distribution:— Entoloma dragorufescens is described from material to date only collected from the coast of Santa Catarina.

Additional material examined:— BRAZIL. Santa Catarina: Itapoá, Volta Velha Private Natural Heritage Reserve, Sambaqui Trail , 11 December 2012, F. Karstedt et al. FK2111 ( FLOR) ; FK2116 ( FLOR); FK2128 ( FLOR) .

Comments:— Entoloma dragorufescens most closely resembles E. rufum (Romagn. & Gilles) Noordel. & Co-David (2009:173) , an African species that also has a reddish brown pileus and cuboidal basidiospores with elongated angles. However, E. rufum has basidiospores that are larger, 12–17 × 10–14 µm, cheilocystidia that are cylindrical and the hyphae of the pileipellis contain red vacuolar pigment (Romagnesi & Gilles 1979).

Entoloma dragorufescens is phylogenetically related to E. dragoluteum ( Fig. 3 ), but differs macroscopically in the color of the basidiome, which in the former species tends to brownish red and in the latter yellow or ochre, and in the cuspidate papilla in E. dragorufescens versus the well-elongated one of E. dragoluteum .

Entoloma fraternum (Singer) Blanco-Dios, Tarrelos 17: 34. 2015. [≡ Rhodophyllus fraternus Singer, Sydowia 7: 97. 1973.]

Figs. 15 , 17g –j

Description:— Pileus (11–) 17 mm diam., convex with involute margin, dark grey, translucent-striate, glabrous, dry. Pileus context odorless. Lamellae adnate to sinuate, distant, ventricose, grey. Stipe (24–)40 × 1.5 (at the apex)–4 (at the base) mm, apex attenuated, grey, glabrous.

Basidiospores cuboidal with no angles or slightly elongated angles, 4-angled in profile, rarely 3-angled, excluding the projections 7.5–8.7 × 7.5–10 µm [xm = 8.17 (± 0.52) × 8.64 (± 0.75) µm, Q = 1–1.16, Qm = 1.05 (± 0.09), n = 20], including the projections 8.7–10 × 8.7–10 µm [xm = 8.87 (± 0.59) × 9.49 (± 0.59) µm, Q = 1–1.33, Qm = 1.07 (± 0.086), n = 20], and diagonally, 10–12 × 10–12.5 µm [xm = 11.11 (± 0.52) × 11.66 (± 0.68) µm, Q = 1–1.12, Qm = 1.05 (± 0.065), n = 20] thin-walled. Basidia clavate, 37–50 × 10–16 µm (n = 20), hyaline, thin-walled, 4-sterigmate. Cheilocystidia not observed, margin of lamella collapsed. Pleurocystidia and pseudocystidia absent. Lamellar trama composed of parallel, cylindrical or sometimes inflated hyphae, 2.5–17 µm diam. (n = 20), hyaline, thin-walled, septate (distance between septa>200 µm), sub-hymenium branched. Pileitrama composed of radially arranged hyphae, 6.2–19 µm diam. (n = 10), cylindrical, broadly cylindrical or irregular, hyaline, thin-walled, septa distant. Pileipellis a cutis of prostrate, cylindrical hyphae, 2.5–11 µm diam. (n = 160/14), hyaline or with straw yellow intracellular pigment, thin-walled, septa distant. Stipipellis a cutis of cylindrical hyphae, 5–10 µm diam. (n = 20), hyaline or with straw yellow intracellular pigment, thin-walled, septa distant. Caulocystidia dispersed, cylindrical or cylindro-clavate, 43–70 × 6.2–10 µm (n = 6), hyaline or with straw yellow intracellular pigment, thin-walled. Clamp connections present in all tissues. Refractive hyphae absent.

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

Distribution:—To date collected only in Pernambuco (Singer 1973).

Additional material examined:— BRAZIL. Pernambuco: Recife, Two Brothers State Park , 5 July 1960, R . Singer B 3074 (Holotype, BAFC) .

Comments:—The macroscopic description presented here is based on the protologue of the species (Singer 1973) plus observations made on the holotype. The Entoloma fraternum holotype collection is a complete basidiome, with stipe, pileus and lamellae. The basidiome is intact and there is no indication that the collection was sectioned for microscopic analyses. The pileus has a diameter of 11 mm, the lamellae are adnate to sinuate and the apparently fibrous stipe is 24 mm long. Singer (1973) described the pileus as having a diameter of 17 mm and the stipe as being 40 mm long. However, the microscopic characteristics observed in this material are in accordance with those described by Singer (1973).

Horak (1976a) synonymized Entoloma fraternum with E. spadix Hesler (1967:24) . However, the species differ in that the latter has a fibrillose-squamulose brown pileus, 2- or 4-sterigmate basidia, a pileipellis in transition between a cutis and a trichoderm, with inflated or clavate terminal elements filled with brown intracellular pigment, in addition to having abundant refractive hyphae and also hyphae with brilliant granules, according to Noordeloos (1988). Another characteristic that differs is that E. fraternum was described originally as having a translucent-striate pileus, suggesting that it is hygrophanous, while E. spadix was described as non-hygrophanous. Due to these differences, the synonymization proposed by Horak (1976a) is not accepted here.

The morphological characterization of Entoloma fraternum overlaps with other species with cuboidal basidiospores without elongated angles described for Brazil. However, it is the only one with a grey basidiome (dark grey pileus, lamellae and grey stipe) and lacking cheilocystidia. Among the species with cuboidal basidiospores described in the world, E. canoconicum also has a grey basidiome; however, it differs in having a conical pileus and pleurocystidia (Horak 2008).

Entoloma fraternum is apparently not a common species, and new collections are necessary to improve its circumscription. Coimbra (2010) identified a collection as Entoloma aff. spadix , considering it synonymous with E. fraternum ; however, morphological examination suggests that it is another species, mainly because it is characterized by a pinkish brown pileus and fibrillose pileipellis and under microscopy by clavate to broadly clavate cheilocystidia and the presence of refractive hyphae.

All attempts to obtain DNA sequences were unsuccessful.

Figures

FIGURE 3. Phylogenetic reconstruction of the species of Entolomataceae with cuboid basidiospores and related species based on the combined genes (nLSU, mtSSU, rpb2 and tef1). Bootstrap values (> 70%) from the maximum likelihood analysis are indicated above the branches. The species studied here are shown in boldface. AU: Australia, AT: Austria, BZ: Belize, BR: Brazil, CN: China, GY: Guyana, IN: India, MY: Malaysia, NZ: New Zealand, PG: Papua New Guinea, PR: Puerto Rico, RE: La Reunion, UK: Russia, SC: Seychelles, US: United States, VN: Vietnam. Dashed vertical line: have similarity in the morphology but no molecular support.

FIGURE 14. Entoloma dragorufescens: a–b. basidiospores: a. FK2102; b. FK2111; c. basidia (FK2102); d. cheilocystidia (FK2102); e. pileipellis (FK2102); f. caulocystidia. Scales: a–d, f: 10 µm, e: 20 µm.

FIGURE 15. Entoloma fraternum (Singer B3074): a. basidiospores; b. basidia; c. cheilocystidia; d. pileipellis. Scales: a–c: 10 µm, d: 20 µm.

FIGURE 17. Microphotography of basidiospores in electron microscopy: a–c. E. dragoluteum (FK2120); d–f. Entoloma dragorufescens (FK2102); g–j. E. fraternum (B3074); k–m. E. gatesianum (ACM499). Scale: 5 µm.

FIGURE 37. Basidiomas: a. Entoloma caribaeum (FK1790); b–c. E. dragorufescens: b. FK2102; c. FK2116; d–e. E. dragoluteum (FK2131); f–g. E. lycopersicum: f. TBGAG151; g. TBGAG590. Photos: a–e: F. Karstedt; f–g: R. Maziero. Scale: 1 cm.