identifier	taxonID	type	CVterm	format	language	title	description	additionalInformationURL	UsageTerms	rights	Owner	contributor	creator	bibliographicCitation
6E2A87A9F438FFC7C1FCFF35FA98E143.text	6E2A87A9F438FFC7C1FCFF35FA98E143.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Acantholichen dendroideus V. Marcano 2022	<div><p>1) Acantholichen dendroideus V. Marcano, sp. nov.; (Fig. 4)</p> <p>Mycobank MB#838340</p> <p>Diagnosis:— Sicut Acantholichen campestris, sed squamis dense dichotome furcatis differt. Thallus muscicola, microsquamulosus. Squamulae microfruticosae, pruinosae. Soredia nulla. Hyphis tegentibus fibrillas quadratorhombicis, non fibulatis. Acanthohyphidiae 20–27 longae × 5–7 μm crassae, subglobosae vel pyriformae, conspicue spinosae, abundantes.</p> <p>Etymology:—The epithet refers to the characteristic squamules which are divided at the top fine ramifications.</p> <p>Type:— VENEZUELA. Mérida: Parque Sierra Nevada de Mérida, La Mucuy Alta, elev. 2150 m; 5 November 2020, V. Marcano 20-901 (holotype MER, isotype B, private herb. V. Marcano).</p> <p>Description:— Thallus microsquamulose; squamules thin and mostly elongated, 1–2 mm long, 100–180 μm broad, microfruticulose, many growing together, occasionally thus shading one another, olivaceous when fresh, light blue grey when dry, the shaded parts becoming necrotic and pale beige, attached basally to the substrate, densely and dichotomously divided from the tips; microbranches swollen, 1–3(–4) times divided, coral-like, ascendent or erect, 300–350 μm long, 40–60 μm broad. An overall uniformly white-pruinose appearance due to acanthohyphidia. Soredia absent. Thallus in cross section 60–110 μm thick, composed of a thick photobiont (Rhizonema) layer (60–80 μm), a very thin paraplectenchymatous cortex and pale brown medulla. Photobiont forming clusters of coiled cyanobacterial filaments (chroococcoid; 7–14 μm diam.) inside the thallus microsquamulose, wrapped in a dense hyphal sheath formed by jigsaw-puzzle-shaped cells. Acanthohyphidia variable in size, usually small (4–8 μm × 4–5 μm), irregular, subglobose to pyriform, sometimes large [20–24(–27) × 5–7 μm] and then elongate, apically thickened, conspicuously spiny, abundant, present on upper and lower surfaces. Clamp connections not observed.</p> <p>Chemistry:—Thallus K–, C–, KC–, P–; medulla K–, C–, KC–, P–, N + (pink) (n = 6; V. Marcano). No lichen compounds detected by TLC.</p> <p>Distribution and Ecology:—This species is known only from the well-developed type collection. It was found on mosses in a humid, shady disturbed forest growing on Persea americana P. Miller (1768: HW’95) associated with Cora, Pseudoparmelia Lynge (1914: 15) and Usnea species at 2100–2550 m (Fig. 3A).</p> <p>Remarks:—The genus Acantholichen, previously thought to be monospecific (Lawrey et al. 2009), currently includes six species, viz., A. sorediatus Dal Forno, Sipman &amp; Lücking (2016: 49) and A. pannarioides from Costa Rica (this latter also from Venezuela) (Jørgensen 1998), A. albomarginatus Dal Forno, Marcelli &amp; Lücking (2016: 43) and A. campestris Dal Forno, Spielmann &amp; Lücking (2016: 44) from Brazil, A. galapagoensis Dal Forno, Bungartz &amp; Lücking (2016: 44) from the Galápagos islands, and A. variabilis Dal Forno, Coca &amp; Lücking (2016: 51) from Colombia (Dal Forno 2015, Dal Forno et al. 2016, 2017).</p> <p>Acantholichen dendroideus is morphologically distinct from all other known Acantholichen species. It is characterized by a light blue-grey (when dry) thallus, ascendent, dichotomously and densely branched (from the tips) microsquamules, a pruinose surface and large acanthohyphidia. The new species somewhat resembles A. campestris from Brazil and A. galapagoensis from the Galápagos islands. Both species lack soredia and have a branched thallus and pyriform acanthohyphidia. However, in A. campestris the squamules are not dichotomously branched, are grey (when dry), and show a microfruticulose appearance while growing into vertical structures; the acanthohyphidia are small (10–15 × 6–8 μm). It is the only species known that grows on rocks. In contrast A. galapagoensis has dark olivaceous grey (when dry), elongated, intricate and tiled squamules, a non-fruticose appearance, small to medium acanthohyphidia (12–16 × 6–10 μm), and grows on mosses and liverworts (Dal Forno et al. 2016).</p> <p>Additional specimens examined (paratype):— Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua, cloud forests, elev. 2550 m; June 2020, V. Marcano &amp; L. Castillo no. 20-416 (MER, private herb. V. Marcano).</p></div> 	https://treatment.plazi.org/id/6E2A87A9F438FFC7C1FCFF35FA98E143	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Marcano, Vicente	Marcano, Vicente (2022): Eight new species of lichenized Basidiomycota in the genera Acantholichen, Cyphellostereum and Dictyonema s. str. (Agaricales, Hygrophoraceae) from northern South America. Phytotaxa 574 (3): 199-225, DOI: 10.11646/phytotaxa.574.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.574.3.1
6E2A87A9F439FFC5C1FCFAA7FC23E63F.text	6E2A87A9F439FFC5C1FCFAA7FC23E63F.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Cyphellostereum mucuyense V. Marcano 2022	<div><p>2) Cyphellostereum mucuyense V. Marcano, sp. nov.; (Fig. 5)</p> <p>Mycobank MB#838446</p> <p>Diagnosis:— Sicut Dictyonema metallicum, sed cellulis quadrato-rhombici nullis differt. Thallus muscicola vel terricola, sat tenuis. Prothallus nullus. Hyphae fibulatae. Haustoria nulla. Hymenocarpus resupinatus. Hymenium N non reagens. Basidiosporae subglobosae, 5–7 μm crassae.</p> <p>Type:— VENEZUELA. Mérida: Sierra Nevada de Mérida, San Jerónimo cloud forests, near Mucuy Alta, elev. 2150 m, terricolous; 30 October 2020, V. Marcano 20-567 (holotype MER, isotype B, private herb. V. Marcano).</p> <p>Etymology:—The epithet refers to the locality where the type specimens were collected.</p> <p>Description:— Thallus growing on and among bryophytes or soils, crustose-filamentous, dark green, developing a mat of ± individual to slightly interwoven fungal-cyanobacterial fibrils connected by a very thin hypothallus; prothallus absent. Fibrils horizontally arranged and closely appressed. Photobiont layer (50–120 μm) composed of cyanobacterial filaments covered by thin elongated fungal cells, not forming jigsaw-puzzle-shaped cells; cyanobacterial filaments not branched, composed of 8–10 μm wide and 4–9 μm high, green cells, mostly square to elongate–cylindrical, in chains, not penetrated by tubular fungal hyphae (haustoria); heterocytes rare, pale to slightly bright yellow, 7–8 μm wide and 4–5 μm high; cells of hyphal sheath regular in lateral outline, 2–4 μm thick; hyphae of medulla and hypothallus straight, hyaline, much branched, 3.5–5 μm thick. Clamp connections present, not common; hypothallus formed by interwoven, strongly agglutinate, generative hyphae.</p> <p>Hymenophore (when fresh) developed as effuse patches, resupinate-corticioid, 30–80 mm diameter, white, without distinct margins, with finely arachnoid surface; composed of a paraplectenchymatous layer resting on hyphae emerging from supporting thallus; in section 40–50 μm thick, composed of 3.5–5 μm thick hyphae; hymenium composed of numerous, palisade–like basidioles and scattered basidia; basidioles 20–30 × 5–6 μm; basidia 25–40 × 5–7 μm; basidiospores subglobose, non-septate, hyaline, 5–7 μm.</p> <p>Chemistry:—Thallus K–, C–, KC–, P–; medulla K–, C–, KC–, P–, N –, ER–; basidiocarp K–, C–, KC–, P–, N –, ER– (n = 6). No lichen compounds detected by TLC.</p> <p>Distribution and Ecology:—This species is known only from the well-developed type collection. It was found growing on mosses and acid soils in shady and very humid rainforest at 2150 m (Fig. 4A). This is the first record of the genus Cyphellostereum in Venezuela.</p> <p>Remarks:—Morphologically, C. mucuyense is a typical representative species of Cyphellostereum. It is characterized by an appressed filamentous thallus, a distinct, thin hypothallus, clamp connections, resupinate basidiomata (hymenophore) and absence of jigsaw-puzzle-shaped hyphal cells. Morphologically it resembles Dictyonema metallicum Lücking, Dal Forno &amp; Lawrey (Lücking et al. 2013a: 22) in having appressed, horizontal fibrils and absence of a discernible medulla. The latter differs in the presence of a prothallus, an irregular photobiont layer, the dark greenish color of the cyanobacterial photobiont, a hyphal sheath formed by jigsaw-puzzle-shaped cells, and the absence of clamp connections. Cyphellostereum mucuyense could also be confused with D. obscuratum Lücking, Spielmann &amp; Marcelli (Lücking et al. 2013a: 24) as both species are characterized by a strongly compressed mat of irregularly arranged, densely interwoven fibrils, but the latter species forms jigsaw-puzzle-shaped cells and lacks clamp connections (Lücking et al. 2013).</p> <p>Anatomically, C. mucuyense agrees with other Cyphellostereum species in the simple hyphal sheath around the cyanobacterial filaments, the comparatively narrow filament cells, and the absence of haustoria (Yanez et al. 2012, Lücking et al. 2013a, Dal Forno 2015; Dal Forno et al. 2013, 2016). The tiny fibrils of C. mucuyense are also reminiscent of those of Cyphellostereum. However, the resupinate-corticioid hymenophore is more reminiscent of Dictyonema s.str. (Lücking &amp; Timdal 2016). Another species confirmed in the latter genus based on molecular data, D. huaorani, also lacks jigsaw-puzzle-shaped hyphal cells and haustoria (Schmull et al. 2014). Molecular studies are needed to determine the position of this taxon in the Dictyonema clade.</p> </div>	https://treatment.plazi.org/id/6E2A87A9F439FFC5C1FCFAA7FC23E63F	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Marcano, Vicente	Marcano, Vicente (2022): Eight new species of lichenized Basidiomycota in the genera Acantholichen, Cyphellostereum and Dictyonema s. str. (Agaricales, Hygrophoraceae) from northern South America. Phytotaxa 574 (3): 199-225, DOI: 10.11646/phytotaxa.574.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.574.3.1
6E2A87A9F43BFFC2C1FCFDADFDDCE5CF.text	6E2A87A9F43BFFC2C1FCFDADFDDCE5CF.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Dictyonema andinum V. Marcano 2022	<div><p>3) Dictyonema andinum V. Marcano, sp. nov.; (Fig. 6)</p> <p>Mycobank MB#838341</p> <p>Diagnosis:— Sicut Dictyonema irrigatum, sed fibrilis ascendentibus vel verticalibus differt. Thallus muscicola vel terricola, crassiusculus. Hyphis tegentibus fibrillas quadrato-rhombicis, undulatis, fibulatis. Haustoria praesentia. Filamenta 20–25 μm lata. Hymenocarpus corticoideus. Hymenium N reagens (rubescens), sporis guttaeformibus, hyalinis, non septatis, 5–6 μm longis.</p> <p>Type:— VENEZUELA. Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua, cloud forests, elev. 2650 m; 12 October 2020, V. Marcano &amp; L. Castillo no. 20-535 (holotype MER, isotype B, private herb. V. Marcano).</p> <p>Etymology:—The epithet refers to the geographical region where the type specimens were collected.</p> <p>Description:— Thallus filamentous, dark blue-green, covering larger areas of the substrate, in irregular, confluent patches up to 45 cm across, forming a crust usually over bryophytes or soil, composed of loosely interwoven, dark green to bluish green fibrils leaving interspaces and bordered by a discrete, white margin (prothallus). Fibrils irregularly arranged, ascending or erect, forming an irregular, lumpy surface. Thallus furnished with irregular, small tufts, projecting vertically from the substrate, consisting of pale brown or green fibrils. Thallus (when fresh) in section 2–2.4 mm thick, composed of a thick photobiont (Rhizonema) layer (1.25–1.75 mm) and a thin, pale brown medulla (375–500 μm) (hypothallus); photobiont layer composed of numerous cyanobacterial filaments wrapped in a closed hyphal sheath formed by jigsaw-puzzle-shaped cells; cyanobacterial filaments not branched, composed of 20–25 μm wide and 7–8(–10) μm high, bluish green cells penetrated by tubular fungal hyphae (haustoria); heterocytes frequent, pale to slightly bright yellow, 10–12(–14) μm wide and 3–4(–5) μm high; cells of hyphal sheath variably wavy in lateral outline, 4–6 μm thick; hyphae of medulla, hypothallus and white margin (prothallus) straight, hyaline, much branched, 5–7 μm thick. Clamp connections present but sparse on the hyphae; hyphal sheath finely papillose towards the tips of the filaments; hypothallus and prothallus formed by interwoven, strongly agglutinate, generative hyphae; often fertile.</p> <p>Hymenophore (when fresh) developed as bulging, stereoid-corticioid patches from the underside of the thallus margins and soon becoming inverted and exposed, white patches, 6–14 mm wide; smooth, with pruinose upper surface and spongy lower surface; hymenophore in section 150–350 μm thick, composed of a paraplectenchymatous layer connected to loose medullary hyphae; hymenium composed of numerous, palisade-like basidioles and scattered basidia; basidioles 25–35 × 5–6 μm; basidia 30–40 × 5–7 μm, 4–sterigmate; basidiospores ellipsoid to narrowly drop-shaped, non-septate, hyaline, 5–6(–7) × 3.8–4(–5) μm.</p> <p>Chemistry:—Thallus K–, C–, KC–, P–; medulla K–, C–, KC–, P–, N + (dark red), ER+ (purple); basidiocarp K–, C–, KC–, P–, N + (red), ER+ (bluish purple) (n = 8). No lichen compounds detected by TLC.</p> <p>Distribution and Ecology:— D. andinum is the most abundant of all the species of Dictyonema s.str. found in the Venezuelan Andes. Six populations were observed in an area ca. 2 km 2. It was found growing on mosses and acid soils, associated with Dibaeis absoluta and Cladonia ceratophylla (Swartz 1788: 147) Sprengel (1827: 271) in partly exposed and very humid rainforest at 2000–2450 m (Fig. 5A).</p> <p>Remarks:—Morphologically, D. andinum is a typical representative of Dictyonema s.str. This species is characterized by irregularly arranged, broad, ascending, or erect fibrils, thick photobiont layer and hypothallus, finely papillose hyphae towards the tips of the filaments, clamp connections, and a white, stereoid-corticioid hymenophore. Commonly the thallus is slightly thicker when the specimen is fresh (humid). Positive (red) N spot test in the hymenophore and medulla are notable and suggest the presence of certain compounds which are absent in other Dictyonema species.</p> <p>Dictyonema andinum could be confused with D. irrigatum (Berkeley &amp; M.A. Curtis 1860: 123) Lücking (2013b: 30). However, D. irrigatum has irregularly appressed, horizontal to erect fibrils, and a hymenophore developed as resupinate patches. Its spores are also slightly longer (7–9 μm) than those of D. andinum. Dictyonema irrigatum is known only from China and the Andaman and Nicobar Islands (Lücking et al. 2013 a, Jagadesh-Ram &amp; Singh 2014) (Table 1).</p> <p>Additional specimens examined (paratypes):— Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua, cloud forests, elev. 2650 m; 12 October 2020, V. Marcano &amp; L. Castillo no. 20-540 (MER, private herb. V. Marcano); Parque Sierra Nevada de Mérida, road towards Lake Coromoto, cloud forest, elev. 2000 m, V. Marcano &amp; L. Castillo 21-119, 21-120 (MER, private herb. V. Marcano).</p></div> 	https://treatment.plazi.org/id/6E2A87A9F43BFFC2C1FCFDADFDDCE5CF	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Marcano, Vicente	Marcano, Vicente (2022): Eight new species of lichenized Basidiomycota in the genera Acantholichen, Cyphellostereum and Dictyonema s. str. (Agaricales, Hygrophoraceae) from northern South America. Phytotaxa 574 (3): 199-225, DOI: 10.11646/phytotaxa.574.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.574.3.1
6E2A87A9F43DFFC0C1FCFF5FFE9EE01B.text	6E2A87A9F43DFFC0C1FCFF5FFE9EE01B.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Dictyonema duidense V. Marcano 2022	<div><p>4) Dictyonema duidense V. Marcano, sp. nov.; (Fig. 7)</p> <p>Mycobank MB#838342</p> <p>Diagnosis:— Sicut Dictyonema barbatum sed hymenocarpis resupinatis, irregularis differt. Thallus corticola, byssaceus, crassus, pagina areolata, rugosa, hyphis non fibulatis. Hymenium N non reagens. Sporae guttaeformes, hyalinae, non septatae, 7–8 μm longae, 2–4 μm latae.</p> <p>Type:— VENEZUELA. Amazonas: Alto Orinoco, summit northern Cerro Duida, growing on tree trunks at margin of small tepuian forests, elev. 2100 m, March 1996, L. Galiz &amp; V. Marcano AMA-757 (holotype MER, isotype B, private herb. V. Marcano).</p> <p>Etymology:—The epithet refers to the locality where the type specimens were collected.</p> <p>Description:— Thallus shelf-like, corticolous, byssaceous, filamentous, epiphytic on tree trunks, covering larger areas of the substrate with a thick crust, in irregular, confluent patches up to 35 cm across, composed of densely arranged, dark aeruginous fibrils with distinct interspaces resting on a thick, byssoid, irregularly interwoven medulla (hypothallus), visible as narrow, 0.8–1.1 mm wide marginal zone, strongly contrasting with the aeruginous fibrils. Lobes projecting vertically from the substrate, semicircular, coated, dark blue-green, very broad, 15–25 cm; surface areolate, rugose, with entire, white margins, 1–1.5 cm wide, lacking photobiont filaments; photobiont layer composed of numerous cyanobacterial filaments wrapped in a closed hyphal sheath formed by jigsaw-puzzle-shaped cells; cyanobacterial filaments not branched, composed of 20–25 μm wide and 4–6 μm high, bluish green cells penetrated by tubular fungal hyphae (haustoria). Thallus in section 3–6(–7) mm thick, not forming a distinct photobiont layer and medulla but instead composed of aeruginous fibrils connected at base (underside) to a pale brown, loosely woven hypothallus. Clamp connections absent.</p> <p>Hymenophore forming irregular, reticulated, resupinate patches dispersed on the underside, with entire margin, whitish, smooth surface; hymenophore composed of a paraplectenchymatous layer connected to loose medullary hyphae; hymenium composed of numerous, palisade-like basidioles and scattered basidia; basidiospores ellipsoid to narrowly drop-shaped, non-septate, hyaline, 7–8 × 2–4 μm.</p> <p>Chemistry:—Thallus K–, C–, KC–, P–; medulla K–, C–, KC–, P–, N –, ER–; basidiocarp K–, C–, KC–, P–, N –, ER– (n = 6). No lichen compounds detected by TLC.</p> <p>Distribution and Ecology:— Dictyonema duidense is found growing as an epiphyte on tree bark in altotepuian forests at 1500–2100 m. It is known only from the type locality.</p> <p>Remarks:— Dictyonema duidense is another species in the complex formerly recognized as the single species, Dictyonema sericeum (Parmasto 1978). In their treatment of Dictyonema s. str., Lücking et al. (2013a,b) indicated that the phenotype usually identified with the name D. sericeum is a complex of several, phylogenetically distinct species, differing morphologically in the orientation and arrangement of the fibrils and in the morphology of the hymenophore. According to Lücking et al. (2014b) the thallus of D. sericeum type is much more compacted than any of the species collected in South America, indicating, along with the geographic range, that D. sericeum s.str. is a distinct taxon possibly restricted to the Caribean.</p> <p>Dictyonema duidense is characterized by a shelf-like filamentous thallus, with thick, very broad lobes, areolate, rugose surface and lacking clamp connections. It is very similar to D. barbatum Dal Forno, Bungartz &amp; Lücking (Dal Forno et al. 2017: 62) from the Galápagos Islands (Dal Forno 2015, Dal Forno et al. 2017). Both species have a shelflike filamentous thallus and lack clamp connections on the hyphae but D. barbatum is distinguished by the color of the prothallus (old specimens with a darkened hue, yellow to light brown) and the continuous hymenophore. Dictyonema duidense resembles D. excentricum C. Agardh (Kunth 1822: 1). This latter is characterized by thick, horizontally arranged bundles of fibrils and is known only from French Guiana.</p> <p>Additional specimens examined (paratypes):— Amazonas: summit northern Cerro Duida, growing on tree bark in small tepuian forests, elev. 1500 m, March 1996, L. Galiz &amp; V. Marcano AMA-539, 540 (TFAZ, VEN, private herb. V. Marcano).</p></div> 	https://treatment.plazi.org/id/6E2A87A9F43DFFC0C1FCFF5FFE9EE01B	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Marcano, Vicente	Marcano, Vicente (2022): Eight new species of lichenized Basidiomycota in the genera Acantholichen, Cyphellostereum and Dictyonema s. str. (Agaricales, Hygrophoraceae) from northern South America. Phytotaxa 574 (3): 199-225, DOI: 10.11646/phytotaxa.574.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.574.3.1
6E2A87A9F43EFFDEC1FBFB4FFB3DE587.text	6E2A87A9F43EFFDEC1FBFB4FFB3DE587.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Dictyonema laurae V. Marcano 2022	<div><p>5) Dictyonema laurae V. Marcano, sp. nov.; (Fig. 8) Mycobank MB#840644</p> <p>Diagnosis:— Sicut D. subsericeum, sed hyphis non fibulatis differt. Thallus muscicola, byssaceus, tenuis, marginibus elevatis, pagina hirsuta. Hymenocarpus resupinatus. Hymenium N reagens (roseus). Sporis elliptis, hyalinis, non septatis, 10–12 μm longis, 7–8 μm latis.</p> <p>Type:— VENEZUELA. Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua cloud forests, elev. 2650 m, 17 July 2021, V. Marcano 21-65 (holotype MER, isotype B, private herb. V. Marcano).</p> <p>Etymology:—The epithet is dedicated to the naturalist Laura Castillo who has contributed with the author to the study of lichens and in discovering new species.</p> <p>Description:— Thallus on liverworts or mosses, byssaceous, filamentous, forming a thin crust, epiphytic on tree branches. Thallus surface irregular, more or less continuous, covering up to 12 cm across, greenish blue, developing a mat of cyanobacterial fibrils leaving interspaces, bordered by a discontinuous, fibrillose, narrow, white margin projecting vertical from the substrate, 2–4 mm broad; surface hirsute. Thallus (when fresh) in section 1.75–2 mm thick, composed of a loose, white medulla (0.75–1 mm) (hypothallus) and a broad, very loose aeruginous upper layer (1–1.25 mm) composed of irregularly arranged, long, white fibrils mixed with photobiont filaments (Rhizonema); cyanobacterial filaments wrapped in a closed hyphal sheath formed by jigsaw puzzle-shaped cells; cyanobacterial filaments not divided, composed of 12–17 μm wide and 7–8 μm high, bluish green cells penetrated by tubular fungal hyphae (haustoria); heterocytes frequent, bright yellow, elliptic, 10–12 μm wide and 5–8 μm high; hyphae associated with hyphal sheath straight, hyaline, 5–7 μm thick, smooth towards the tips of the filaments; clamp connections absent; hyphal sheath waxy in lateral outline.</p> <p>Hymenophore (when fresh) developed as small, angular to elongate, white, resupinate patches dispersed on the underside and resembling small, isomorphic attachment, small hapters (250–300 × 300–500 μm) with white, finely reticulate surface and entire margins; hymenophore composed of a paraplectenchymatous layer connected to loose medullary hyphae, 6.25–7.5 μm wide; hymenium composed of numerous, palisade-like basidioles and scattered basidia; basidia 32–39 × 5–7 μm, 4-sterigmate; basidiospores elliptic, non-septate, hyaline, 10–12 × 7–8 μm.</p> <p>Chemistry:—Thallus K–, C–, KC–, P–; medulla K–, C–, KC–, P–, N + (pink), ER+ (pale bluish purple); basidiocarp K–, C–, KC–, P–, N –, ER– (n = 6). No lichen compounds detected by TLC.</p> <p>Distribution and Ecology:— Dictyonema laurae was found growing as an epiphyte on bryophytes in the canopy of partly shady and very humid rainforests at elev. 2450–2650 m (Fig. 8A). It is associated with Grammitis, Cladonia and Parmotrema species.</p> <p>Remarks:— Dictyonema laurae is characterized by a thallus forming a thin crust (1.75–2 mm), with an irregular, continuous, greenish blue, hirsute surface, with discontinuous, fibrillose, narrow margins ascending from the substrate, hapteriform hymenophore patches with finely reticulate surface and entire margins, absence of clamp connections on the hyphae, large basidiospores, and a positive N spot test (pink). Dictyonema laurae is similar to D. subsericeum; which occupies the same habitat and has hymenophores resembling attachment hapters. However, D. subsericeum has a thallus forming a thicker crust (3–5 mm), with filamentous lobes, semicircular or hemispherical, projecting horizontally from the substrate, is variable in color (white, greenish blue, brown), size and shape (semicircular and hemispherical), with clamp connections on the hyphae, wider cyanobacterial cells, with a larger, irregular hapteriform hymenophore with more or less smooth or pruinose surface and fibrillose margins, smaller basidiospores, and a negative N spot test.</p> <p>Dictyonema laurae is also like D. hapteriferum Lücking, Dal Forno &amp; Wilk (Lücking et al. 2013b: 11) and D. subinvolutum. However, D. hapteriferum is characterized by an absence of clamp connections, cyanobacterial filaments composed of 10–12 μm wide cells, a hymenophore resembling large attachment hapters but has semicircular, shelf-like, filamentous lobes and hymenophore with beige surface; it is known only from Bolivia and Perú. Dictyonema subinvolutum has a thallus developing a mat of interwoven fungal-cyanobacterial fibrils, leaving interspaces connected by a defined hypothallus; the cyanobacterial filaments are 12–15 μm wide, have clamp connections, and the basidiocarp surface is pruinose with slightly involute margins. Both species D. laurae and D. subinvolutum show a positive N spot test (pink).</p> <p>Additional specimens examined (paratypes):— Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua cloud forests, elev. 2450 m, 17 July 2021, V. Marcano 21-78, 21-79 (MER, private herb. V. Marcano).</p></div> 	https://treatment.plazi.org/id/6E2A87A9F43EFFDEC1FBFB4FFB3DE587	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Marcano, Vicente	Marcano, Vicente (2022): Eight new species of lichenized Basidiomycota in the genera Acantholichen, Cyphellostereum and Dictyonema s. str. (Agaricales, Hygrophoraceae) from northern South America. Phytotaxa 574 (3): 199-225, DOI: 10.11646/phytotaxa.574.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.574.3.1
6E2A87A9F420FFDEC1FCFDEBFAE2EC57.text	6E2A87A9F420FFDEC1FCFDEBFAE2EC57.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Dictyonema subinvolutum V. Marcano 2022	<div><p>6) Dictyonema subinvolutum V. Marcano, sp. nov.; (Fig. 9)</p> <p>Mycobank MB#838447</p> <p>Diagnosis:— Sicut Dictyonema obscuratum, sed hyphis fibulatis differt. Thallus muscicola vel terricola, crassiusculus. Prothallus nullus. Hyphis tegentibus fibrillas quadrato-rhombicis. Haustoria praesentia. Filamenta 12–15 μm lata. Hymenocarpus resupinatus, pruinosus, margine subinvoluto. Hymenium N reagens (roseus). Sporis guttiformis, hyalinis, non septatis, 6–7 μm longis, 4–5 μm latis.</p> <p>Type:— VENEZUELA. Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua cloud forests, elev. 2650 m; 5 June 2020, V. Marcano &amp; L. Castillo 20-411 (holotype MER, isotype B, private herb. V. Marcano).</p> <p>Etymology:—The epithet refers to the slightly involute hymenophore margins.</p> <p>Description:— Thallus growing on soil and among bryophytes, filamentous, dark blue-green, moderately thick, developing a mat of interwoven fungal-cyanobacterial fibrils, leaving interspaces connected by a defined hypothallus; prothallus absent. Fibrils markedly ascendent, with yellow or pale brown apices, forming an irregular, rough surface. Thallus (when fresh) in section 1.75–2.3 mm thick, composed of a thick, loose, photobiont (Rhizonema) layer (1–1.3 mm) and a thick, pale brown medulla (0.75–1 mm) (hypothallus); photobiont layer composed of numerous cyanobacterial filaments wrapped in a closed hyphal sheath formed by jigsaw-puzzle-shaped cells; cyanobacterial filaments occasionally branched, composed of 12–15(–17) μm wide and 5–7 μm high, bluish green cells penetrated by tubular fungal hyphae (haustoria); heterocytes frequent, pale to slightly bright yellow, 8.5–11 μm wide and 2–5.5 μm high; cells of hyphal sheath variably wavy in lateral outline, 4–5 μm thick; hyphae of hypothallus straight, branched, hyaline, smooth, 7–8 μm thick. Clamp connections present.</p> <p>Hymenophore (when fresh) developed as effuse patches, 3–7 mm diameter, white, resupinate, with slightly involute margins and a smooth, pruinose surface; hymenophore in section 120–130 μm thick, composed of a paraplectenchymatous layer connected to loose medullary hyphae, 5–6 μm wide; hymenium composed of numerous, palisade-like basidioles and scattered basidia; basidiospores drop-shaped, non-septate, hyaline, 6–7 × 4–5 μm.</p> <p>Chemistry:—Thallus K–, C–, KC–, P–; medulla K–, C–, KC–, P–, N + (pink), ER+ (pale bluish purple); basidiocarp K–, C–, KC–, P–, N + (pink), ER+ (pale bluish purple) (n = 6). No lichen compounds detected by TLC.</p> <p>Distribution and Ecology:— Dictyonema subinvolutum was found growing on mosses and acid soils in shady and very humid rainforest at elev. 2250 m (Fig. 7A). This species is only known from the well-developed type collection.</p> <p>Remarks:— Dictyonema subinvolutum is readily distinguished by its moderately thick thallus, markedly ascendent fibrils, a thick hypothallus, the presence of clamp connections, resupinate, pruinose, N + pink basidiocarps, and the lack of a prothallus. The medulla turning pink by the N spot test appears to be a diagnostic feature due to its occurrence only in this taxon among the Dictyonema specimens examined. Dictyonema subinvolutum is like D. obscuratum. Both species are characterized by numerous cyanobacterial filaments covered by fungal hyphae, forming jigsaw-puzzleshaped cells. However, D. obscuratum has strongly compressed mats of irregular, densely interwoven, very dark olivegreen fibrils, an indistinct hypothallus, absence of clamp connections and the hyphae are often sparsely and finely papillose towards the tips. Furthermore, D. obscuratum has slightly longer spores (7–9 μm) than D. subinvolutum. In addition, D. obscuratum inhabits the Cerrado vegetation of Brazil, where it is found growing on tree trunks (Lücking et al. 2013b) (Table 1). Dictyonema subinvolutum could also be confused with D. schenckianum (Müller Argoviensis 1891: 234) Zahlbruckner (1931: 748). However, the type material of D. schenckianum lacks clamp connections and presents a combed appearance (Lücking et al. 2013a). This species is known from Brazil and Colombia (Dal Forno 2015).</p> <p>Additional specimens examined (paratypes):— Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua, cloud forests, elev. 2650 m; 12 October 2020, V. Marcano &amp; L. Castillo no. 20-562 (MER, private herb. V. Marcano).</p></div> 	https://treatment.plazi.org/id/6E2A87A9F420FFDEC1FCFDEBFAE2EC57	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Marcano, Vicente	Marcano, Vicente (2022): Eight new species of lichenized Basidiomycota in the genera Acantholichen, Cyphellostereum and Dictyonema s. str. (Agaricales, Hygrophoraceae) from northern South America. Phytotaxa 574 (3): 199-225, DOI: 10.11646/phytotaxa.574.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.574.3.1
6E2A87A9F421FFDDC1FCFB7EFB0AE7AB.text	6E2A87A9F421FFDDC1FCFB7EFB0AE7AB.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Dictyonema subsericeum V. Marcano 2022	<div><p>7) Dictyonema subsericeum V. Marcano, sp. nov.; (Fig. 10)</p> <p>MycoBank MB#838497</p> <p>Diagnosis:— Sicut Dictyonema sericeum, sed sed hyphis fibulatis differt. Thallus corticola, byssaceus, crassus, pagina hirsuta. Lobis spongiosis, maxime variantibus statura magnitudine latitudine colore et forma. Hymenocarpus resupinatus, hapteriformi. Hymenium N non reagens. Sporis guttaeformibus, hyalinis, non septatis, 4.5–5.5 μm longis, 3.7–4.7μm latis.</p> <p>Type:— VENEZUELA. Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua cloud forests, elev. 2650 m; 5 June 2020, V. Marcano &amp; L. Castillo 20-84 (holotype MER, isotype B, private herb. V. Marcano).</p> <p>Etymology:—The epithet refers to the thallus appearing closely related to the species D. sericeum.</p> <p>Description:— Thallus corticolous, byssaceous, filamentous, forming a thick crust, epiphytic on tree branches. Thallus surface plane or irregular, projecting horizontally from the substrate, covering up to 20 cm diameter, composed of numerous imbricate to partially fused lobes. Lobes projecting parallel from the substrate, semicircular or hemispherical, variable in color, size and shape, when small forming white, filamentous finger-like outgrowths, 4–7 mm broad, when large semicircular, 18–21 mm broad, greenish blue in the bottom side with fibrillose, white margins, 4–5.5 mm broad, and when located in the center of the thallus, brown, forming hemispherical clusters, 5–7(–8) mm broad; surface hirsute. Thallus (when fresh) in section 3–5.8 mm thick, composed of an appressed, pale brown medulla (1.6–2.5 mm) (hypothallus), a broad, very loose, aeruginous photobiont (Rhizonema) layer (1–3 mm) and frequently with an upper layer (0.5–1.25 mm) composed of irregularly arranged, long, white fibrils, lacking photobiont filaments; photobiont layer composed of numerous cyanobacterial filaments wrapped in a closed hyphal sheath formed by jigsawpuzzle-shaped cells; cyanobacterial filaments not divided, composed of 22–27 μm wide and 4.5–7(–8) μm high, bluish green cells penetrated by tubular fungal hyphae (haustoria); heterocytes frequent, bright yellow, elliptic, 13–18 μm wide and 5–8 μm high; hyphae associated with hyphal sheath straight, hyaline, 5–6 μm thick, with clamp connections, finely papillose just before the apices.</p> <p>Hymenophore (when fresh) developed as small, angular to elongate, white, resupinate patches dispersed on the underside and resembling irregular, large (500–1200 μm wide) attachment hapters with white, more or less smooth or pruinose surface, and fibrillose margins; hymenophore composed of a paraplectenchymatous layer connected to loose medullary hyphae, 6–7.5 μm wide; hymenium composed of numerous, palisade-like basidioles and scattered basidia; basidia 28–37 × 4–6 μm, 4-sterigmate; basidiospores globose or subglobose, non-septate, hyaline, 4.5–5.5 × 3.7–4.7 μm.</p> <p>Chemistry:—Thallus K–, C–, KC–, P–; medulla K–, C–, KC–, P–, N –, ER–; basidiocarp K–, C–, KC–, P–, N –, ER– (n = 8). No lichen compounds detected by TLC.</p> <p>Distribution and Ecology:— Dictyonema subsericeum was found growing as an epiphyte on branches in the canopy of rainforests at elev. 2200–2250 m (Fig. 8A). It is known only from the well-developed type collection.</p> <p>Remarks:—Molecular phylogenetic data clearly show that D. sericeum sensu Parmasto contains many different species and even the shelf-like forms representing D. sericeum in a narrow sense are more than one species (Dal Forno et al. 2013). Dictyonema subsericeum is characterized by a thallus forming a thick crust, filamentous lobes, variability of color (white, greenish blue, brown), size and shape (semicircular and hemispherical), with a hirsute surface, fibrillose margins, clamp connections on the hyphae, a hymenophore resembling large, irregular attachment hapters with a white surface and a negative N spot test. Dictyonema subsericeum is like D. sericeum (Dal Forno et al. 2013), D. hapteriferum and D. spongiosum Berkeley &amp; M. A. Curtis (1868: 335), the latter representing the lineage labeled D. sericeum 3 in Dal Forno et al. (2013). These species are characterized by semicircular, shelf-like, filamentous lobes and absence of clamp connections. Dictyonema hapteriferum has aeruginous fibrils bordered by a narrow, byssoid, white margin, a hymenophore resembling attachment hapters with beige, smooth surface. Dictyonema spongiosum has a thick, spongiose upper surface composed of bundles of vertically projecting fibrils and it is known only from Cuba and Guatemala.</p> <p>Dictyonema subsericeum might also be confused with D. irpicinum and D. ligulatum (Krempelhuber 1875: 15) Zahlbruckner (1908: 239). Both species have a lobed surface mottled white and blue-green with coarse, finger-like outgrowths, and hyphae with clamp connections but they are restricted to the Paleotropics (Lücking et al. 2013a, Dal Forno 2015, Dal Forno et al. 2019). Dictyonema subsericeum is like to D. album Lücking &amp; Timdal (2016: 192) from Mauritius. However, this latter species has a combination of irregularly arranged tufts of fibrils that do not form a distinctly layered thallus, being dominated by straight hyphae with very few associated cyanobacterial fibrils, giving the thallus a whitish appearance and it lacks clamp connections on the hyphae (Lücking &amp; Timdal 2016).</p> <p>Additional specimens examined (paratypes):— Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua, cloud forests, elev. 2650 m; V. Marcano &amp; L. Castillo no. 20-85 (MER, private herb. V. Marcano).</p></div> 	https://treatment.plazi.org/id/6E2A87A9F421FFDDC1FCFB7EFB0AE7AB	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Marcano, Vicente	Marcano, Vicente (2022): Eight new species of lichenized Basidiomycota in the genera Acantholichen, Cyphellostereum and Dictyonema s. str. (Agaricales, Hygrophoraceae) from northern South America. Phytotaxa 574 (3): 199-225, DOI: 10.11646/phytotaxa.574.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.574.3.1
6E2A87A9F423FFDBC1FCFBC0FD86E613.text	6E2A87A9F423FFDBC1FCFBC0FD86E613.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Dictyonema umbricola V. Marcano 2022	<div><p>8) Dictyonema umbricola V. Marcano, sp. nov.; (Fig. 11)</p> <p>Mycobank MB#838498</p> <p>Diagnosis:— Sicut Dictyonema discocarpum, sed filamentis furcatis, marginibus albidis, et hyphis fibulatis differt. Thallus muscicola. Hyphothallus praesentia. Hymenocarpus elevatus, disciformibus, margine tomentoso. Hymenium N non reagens. Basidiosporae obovatae, 9–10 μm longae, 4–5 μm crassae.</p> <p>Type:— VENEZUELA. Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua cloud forests, elev. 2550 m; 15 June 2020, V. Marcano &amp; L. Castillo 20-91 (holotype MER, isotype B, private herb. V. Marcano).</p> <p>Etymology:—The epithet refers to the very shady habitat.</p> <p>Description:— Thallus growing on bryophytes, filamentous, dark blue-green, covering shorter areas of the substrate, by irregular, discontinuous patches up to 12 cm across, composed of loosely interwoven, dark green to bluish green fibrils leaving interspaces and bordered by a distinct, discontinuous, white margin (prothallus). Fibrils subascending or horizontal, with whitish apices, broad, more loosely and irregularly arranged and leaving interspaces. Thallus (when fresh) in section 1.25–2.5 mm thick, composed of a thick, loose, photobiont (Rhizonema) layer (0.75–1.75 mm) and a pale brown medulla (0.5–0.75 mm) (hypothallus); photobiont layer composed of cyanobacterial filaments covered by thin elongated fungal cells, forming jigsaw-puzzle-shaped cells; cyanobacterial filaments branched, composed of 13–17 μm wide and 7–10 μm high, bluish green cells, cylindrical, in chains, penetrated by tubular fungal hyphae (haustoria); heterocytes frequent, pale to slightly bright yellow, 12–13 μm wide and 2–3 μm high, narrowly elliptic; cells of hyphal sheath variably wavy in lateral outline, 2–3 μm thick; hyphae of hypothallus straight, branched, hyaline, smooth, 3–5 μm thick. Clamp connections present on the hyphae, abundant.</p> <p>Hymenophore (when fresh) developed as small, rounded to irregular, corticioid patches, dispersed on the upper surface of thallus and resembling apothecial discs, 0.6–2 mm diam., with pale yellowish, smooth surface and white, minutely tomentose margins, 125–200 μm diam.; hymenophore in section 50–120 μm thick, composed of a paraplectenchymatous layer connected to loose medullary hyphae, 5–6 μm wide; hymenium composed of numerous, palisade-like basidioles and scattered basidia; basidiospores (only a few seen) obovate, non-septate, hyaline, 9–10 × 4–5 μm.</p> <p>Chemistry:—Thallus K–, C–, KC–, P–; medulla K–, C–, KC–, P–, N –, ER–; basidiocarp K–, C–, KC–, P–, N –, ER– (n = 8). No lichen compounds detected by TLC.</p> <p>Distribution and Ecology:—This species is known only from the well-developed type collection. It was found growing on mosses in a very shady and humid rainforest at elev. 2000–2650 m (Fig. 9A).</p> <p>Remarks:— Dictyonema umbricola is characterized by horizontal or subascending fibrils, branched cyanobacterial filaments, jigsaw-puzzle-shaped cells, abundant clamp connections on the hyphae and a negative N spot test.This species resembles D. discocarpum Lücking, Dal Forno &amp; Wilk (Lücking et al. 2013b: 7). Both species have a hymenophore composed of disc-shaped patches resembling apothecial discs, with pale yellowish, smooth surface, minutely tomentose margins and jigsaw-puzzle-shaped cells. However, the latter has shelf-like filamentous thallus, a hymenophore in smaller disc-shaped patches (0.3–0.5 mm diam.) dispersed on the underside of the thallus, a hypothallus with byssoid margin, and lacks clamp connections. Dictyonema discocarpum is known only from Bolivia (Lücking et al. 2013b).</p> <p>Some species of the genus Cyphellostereum (Lawrey et al. 2009) have disc-like hymenophores forming resupinate, rounded patches, viz., C. jamesianum Dal Forno &amp; Kaminsky (Dal Forno et al. 2019: 338), and C. georgianum Dal Forno, McMullin &amp; Lücking (Dal Forno et al. 2019: 337). Yet, these species are characterized by a crustose, dark green thallus formed by loose individual fibrils, a fungal sheath consisting of irregular, thin, branched hyphae surrounding the cells, and absence of jigsaw-puzzle-shaped cells. Both species are known only from the southeastern United States and Puerto Rico.</p> <p>Additional specimens examined (paratypes):— Mérida: Parque Sierra Nevada de Mérida, Raiz de Agua, cloud forests, elev. 2650 m; 12 October 2020, V. Marcano &amp; L. Castillo 20-577 (MER, private herb. V. Marcano); Parque Sierra Nevada de Mérida, road towards Lake Coromoto, cloud forest, elev. 2000 m, V. Marcano &amp; L. Castillo 21-110 (MER, private herb. V. Marcano).</p></div> 	https://treatment.plazi.org/id/6E2A87A9F423FFDBC1FCFBC0FD86E613	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Marcano, Vicente	Marcano, Vicente (2022): Eight new species of lichenized Basidiomycota in the genera Acantholichen, Cyphellostereum and Dictyonema s. str. (Agaricales, Hygrophoraceae) from northern South America. Phytotaxa 574 (3): 199-225, DOI: 10.11646/phytotaxa.574.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.574.3.1
6E2A87A9F425FFDBC1FCFD57FA2EE2B8.text	6E2A87A9F425FFDBC1FCFD57FA2EE2B8.taxon	http://purl.org/dc/dcmitype/Text	http://rs.tdwg.org/ontology/voc/SPMInfoItems#GeneralDescription	text/html	en	Acantholichen Lotsy 1907	<div><p>Key to Acantholichen, Cyphellostereum and Dictyonema s.str. in Venezuela</p> <p>1a. Thallus microsquamulose to microfruticulose, pruinose; squamules densely and dichotomously branched from the tips; photobiont forming clusters of short, irregularly coiled threads (chroococcoid) inside the thallus microsquamulose; soredia absent; upper and lower surfaces in microscope view forming apically thickened, distinctly spiny, pyriform to subglobose, variable in size, sometimes elongate hyphae (acanthohyphidia); clamp connections absent............................................. Acantholichen dendroideus</p> <p>1b. Thallus composed of distinct fibrils including cyanobacterial filaments (Rhizonema); acanthohyphidia absent; clamp connections present or absent................................................................................................................................................................................2</p> <p>2a. Thallus directly on bark of trunks or branches; lobes semicircular and/or hemispherical, variable in color, size and shape; basidiocarp N–; Venezuelan Andes or Guayana Highlands................................................................................................................................ (3)</p> <p>2b. Thallus on mosses, liverworts or soil, appressed filamentous or loose and not forming semicircular lobes; basidiocarp N+ or N–; Venezuelan Andes (Sierra Nevada de Mérida)............................................................................................................................... (4)</p> <p>3a (2). Thallus on tree branches; lobes projecting parallel from the substrate, semicircular and hemispherical, variable in color, size and shape; surface hirsute; clamp connections present; basidiocarp with resupinate patches dispersed on the underside and resembling large, irregular attachment, hapters, margin fibrillose; Venezuelan Andes (Sierra Nevada de Mérida)..... Dictyonema subsericeum</p> <p>3b. Thallus on tree trunk, shelf–like filamentous, forming semicircular lobes, projecting upright from the substrate, surface areolate, rugose; clamp connections absent; basidiocarps forming irregular, reticulate, resupinate patches dispersed on the underside, margin entire; Guayana Highlands (Cerro Duida, Alto Orinoco).................................................................................. Dictyonema duidense</p> <p>4a (2). Hymenophore resupinate; jigsaw-puzzle-shaped hyphal sheath present or absent; prothallus absent; clamp connections present or absent.............................................................................................................................................................................................. (5)</p> <p>4b. Hymenophore corticioid; jigsaw-puzzle-shaped hyphal sheath present; prothallus present; clamp connections present.............. (6)</p> <p>5a (4). Jigsaw-puzzle-shaped hyphal sheath absent; fibrils not penetrated by tubular fungal hyphae haustoria, horizontally arranged and closely appressed; cyanobacterial filaments 8–10 μm wide; clamp connections present; basidiocarp surface finely arachnoid, N–................................................................................................................................................................ Cyphellostereum mucuyense</p> <p>5b. Jigsaw-puzzle-shaped hyphal sheath present; fibrils penetrated by tubular fungal hyphae haustoria, ascendent and loosely arranged; cyanobacterial filaments&gt; 10 μm wide; clamp connections present or absent; basidiocarp surface smooth, N+ (pink)......................................................................................................................................................................................................... (7)</p> <p>6a (4). Fibrils irregularly arranged, ascending or erect; cyanobacterial filaments not divided, 20–25 μm wide; hymenophores forming stereoid-corticioid patches, upper surface smooth, lower surface pruinose, spongy, N+ (red)......................... Dictyonema andinum</p> <p>6b. Fibrils horizontal or subascending; cyanobacterial filaments divided, 13–17 μm wide hymenophores raised from the thallus, resembling apothecial discs, surface pale yellowish, smooth, margins white, minutely tomentose; N.......... Dictyonema umbricola</p> <p>7a (5). Thallus developing a mat of interwoven fungal–cyanobacterial fibrils, leaving interspaces; cyanobacterial filaments 12–15 μm wide; clamp connections present; basidiocarp developed as effuse patches, with pruinose surface, margins slightly involute............................................................................................................................................................................. Dictyonema subinvolutum</p> <p>7b. Thallus forming a thin crust (1.75–2 mm), bordered by a discontinuous, narrow, white margin projecting vertical from the substrate; cyanobacterial filaments 12–17 μm wide; clamp connections absent; basidiocarp hapteriform, with finely reticulate surface........................................................................................................................................................................................ Dictyonema laurae</p></div> 	https://treatment.plazi.org/id/6E2A87A9F425FFDBC1FCFD57FA2EE2B8	Public Domain	No known copyright restrictions apply. See Agosti, D., Egloff, W., 2009. Taxonomic information exchange and copyright: the Plazi approach. BMC Research Notes 2009, 2:53 for further explanation.		Plazi	Marcano, Vicente	Marcano, Vicente (2022): Eight new species of lichenized Basidiomycota in the genera Acantholichen, Cyphellostereum and Dictyonema s. str. (Agaricales, Hygrophoraceae) from northern South America. Phytotaxa 574 (3): 199-225, DOI: 10.11646/phytotaxa.574.3.1, URL: http://dx.doi.org/10.11646/phytotaxa.574.3.1
