Differing from S. subscrobiculata in the larger thalli with abundant marginal cilia and marginal and laminal apothecia with veined lower surface and the thickness of the upper cortex with 60–80 μm.

Figure 2. 

Morphology of Sticta amboroensis (holotype) A upper surface B lower surface C–D apothecia with hirsute margins E lower tomentum with cyphellae F marginal cilia G cyphella membrane H excipulum in section. Scale bars: 1 mm (A–F); 5 μm (G); 50 μm (H).

Bolivia. Dept. Santa Cruz; Prov. Florida, Parque Nacional Amboró, above la Yunga Village, senda los Helechos, near view point, 18°02'50"S, 63°54'50"W, elev. 2330 m, Yungas cloud forest with abundant tree ferns, corticolous, 08 June 2011, M. Kukwa 9899 (holotype UGDA, isotype LPB).

Primary photobiont a green alga. Stipe absent. Thallus irregular, up to 25 cm diam., moderately branched, with 3–5 branches per 5 cm radius, branching polytomous; lobes ligulate to laciniate, imbricate to adjacent, involute, with their apices rounded to obtuse and involute and their margins entire to sinuous, not thickened; lobe internodes (3–)7–10(–20) mm long, (4–)8–7(–18) mm broad; thallus coriaceous. Upper surface plane to rugose-pitted towards the centre, beige-brown with darker apices in the herbarium, shiny, with the brown marginal line; surface glabrous, without papillae, without pruina, but with irregular to indistinct, cream maculae, present in older parts of lobes; marginal cilia abundant, simple to fasciculated, light to dark brown, rarely white, up to 0.5 mm long. Apothecia abundant, principally submarginal to laminal, sparse to aggregated, subpedicellate, without pronounced invagination on lower side, up to 3 mm diam.; disc light brown to brown (mature) and yellow (young), shiny to matt; margin entire to crenate, hirsute, with brown hairs, abundant in young apothecia, sparse in old ones. Vegetative propagules absent. Lower surface with somewhat elevated, diffuse ridges, cream to brown towards the centre; primary tomentum dense, sparse towards the margin, thick but thinner towards the margin, spongy to fasciculate, soft, light brown to dark brown; secondary tomentum absent. Rhizines scarce, brown to white, up to 8 mm long. Cyphellae 1–20 per cm² towards the thallus centre and 21–40 per cm² towards the margin, scattered, rounded to irregular, urceolate with wide pore, erumpent to prominent, remaining below the level of the primary tomentum, with the margin raised and involute, cream-coloured, with tomentum; pore 0.5–1.5 mm diam.; basal membrane pruinose in appearance, white to cream, K+ pale yellow, C–, KC–, Pd–. Medulla lax to compact, white, K–, C–, KC–, Pd–. No substances detected by TLC.

Upper cortex paraplectenchymatous, 60–80 μm thick, consisting of 6–7 cell layers with cells 6–16 μm diam. (with smaller cells in outside parts of the cortex), their walls 3–5 μm thick and their lumina rounded to isodiametric, 4–15 μm diam. Photobiont layer 35–50 μm thick, its cells 5–8 μm diam. Medulla 150–220 μm thick, its hyphae 4–5 μm broad, without crystals. Lower cortex paraplectenchymatous, 30–45 μm thick, with 3–4 cell layers; cells 6–17 μm diam., their walls 2–7 μm thick. Hairs of lower primary tomentum up to 1 mm long, in fascicles of 12–20, hyphae unbranched, 5–6 μm wide with rugose walls, forming a brush-like head with free apices. Cyphella cavity up to 300 μm deep; compacted cells of basal membrane rarely with one papillae. Apothecia biatorine, up to 700 μm high, without distinct stipe; excipulum 125–175 μm broad, laterally with projecting hairs, 50 μm long, simple or in groups. Hymenium 100–110 μm high, K+ yellow; epihymenium up to 20 μm high, yellow-brown, K+ yellow intensifying, with gelatinous upper layer, ca. 5 μm high. Asci 6–8-spored, ascospores fusiform, 1–3-septate, 27–42 × 6–10 μm.

Sticta amboroensis is known only from one locality in Parque Nacional Amboró in Department Santa Cruz, where it grows on tree bark at altitude 2330 m.

The name refers the Parque Nacional Amboró, where the species was found.

Bolivia. Dept. Santa Cruz; Prov. Florida, Parque Nacional Amboró, above la Yunga Village, senda los Helechos, near view point, 18°02'50"S, 63°54'50"W, elev. 2330 m, Yungas cloud forest with abundant tree ferns, 08 June 2011, M. Kukwa 9899a (LPB, UGDA).

Sticta amboroensis forms an isolated lineage not far from other green algal species, such as S. pulmonarioides B. Moncada & Coca and S. subscrobiculata (Nyl.) Gyeln. These species are characterised by a similar morphology, but clearly distinguished phylogenetically. In S. subscrobiculata, the lobes are sparsely branched and pleurotomous and the marginal cilia are sparse to absent, although a cilia-like extension of the lower tomentum is usually visible (Moncada 2012). In the case of S. pulmonarioides, thallus is smaller, up to 15 cm in diam., with sparse, mainly submarginal apothecia. In addition, the lower tomentum is sparse over the entire lower surface (Moncada et al. 2013a).

Differing from S. narinioana in the presence of laminal isidia and in the absence of apothecia, as well as the less densely arranged cyphellae.

Figure 3. 

Morphology of Sticta aymara (holotype) A upper surface with isidia B lower surface showing shallow ridges (visible on right-hand lobe after removal of tomentum) C laminal and branched isidia D tomentum and cyphellae. Scale bars: 1 mm.

Bolivia. Dept. La Paz; Prov. Nor Yungas, Parque Nacional y Área Natural de Manejo Integrado Cotapata, near Urpuma colony, 16°13'20"S, 67°52'34"W, elev. 1989 m, Yungas montane forest, 30 June 2010, A. Flakus 17220 & P. Rodriguez-Flakus (holotype KRAM, isotype LPB).

Primary photobiont cyanobacterial (Nostoc). Stipe absent. Thallus orbicular to irregular, up to 5 cm diam., sparsely branched, with 0–2 branches per 5 cm radius, branching pleurotomous; lobes suborbicular to flabellate, interspaced to adjacent, plane to undulate, with their apices rounded and revolute and their margins entire to sinuous, not thickened; lobe internodes (1–)2–4(–7) mm long, (3–)5–6(–10) mm broad; thallus subcoriaceous. Upper surface smooth to pitted or rugose towards the centre, brownish-yellow with darker apices in the herbarium, shiny; surface glabrous, without papillae and pruina, but with irregular, scattered, yellow maculae; marginal cilia absent. Apothecia absent. Vegetative propagules present, abundant, in the form of isidia, predominantly laminal, aggregate, richly branched from the beginning, isidial branches cylindrical to coralloid, vertical, up to 0.6 mm long and 0.05 mm broad, darker than the thallus, grey, shiny; in cross-section, round or rarely slightly flattened. Lower surface with somewhat elevated, diffuse ridges, yellow to brown towards the centre; primary tomentum dense to the margin, thick but thinner towards the margin, spongy to fasciculate, soft, golden to chocolate; secondary tomentum present, arachnoid. Rhizines absent. Cyphellae sparse, 1–10 per cm² towards the thallus centre and 1–20 per cm² towards the margin, scattered, angular to irregular, urceolate with wide pore, prominent, remaining below the level of the primary tomentum, with the margin raised and involute, cream-coloured, with or without tomentum; pore 0.25–0.75 mm diam.; basal membrane ± smooth, white, K–, C–, KC–, Pd–. Medulla compact, cream, K–, C–, KC–, Pd–. No substances detected by TLC.

Upper cortex paraplectenchymatous, 15–40 μm thick, consisting of 2–3 cell layers with cells 7–18 μm diam. (with smaller cells in outside parts of the cortex), their walls 0.6–2 μm thick and their lumina rounded to isodiametric, 6–17 μm diam. Photobiont layer 25–70 μm thick, its cells 4–20 μm diam. Medulla 30–70 μm thick, its hyphae 2.5–6 μm broad, without crystals. Lower cortex paraplectenchymatous, 30–50 μm thick, with 3 cell layers; cells 6–20 μm diam., their walls 2–4 μm thick. Hairs of lower primary tomentum 150–400 μm long, in fascicles of more than 20, hyphae simple, septate with interlocked apices. Cyphella cavity up to 130 μm deep; cells of basal membrane without papillae or with single papillae. Apothecia not observed.

Sticta aymara is known only from the type locality in the Department La Paz, at an altitude of 1989 m.

The name refers the Aymara people in the Andes and Altiplano regions of South America who coined the term Yungas.

Although this new taxon is known from a single collection only, we decided to describe it formally, as the material is well-developed and phylogenetically distinctive, shown by two sequences generated from different pieces of the specimen. Sticta aymara forms a sister clade with the also newly-described S. narinioana from Colombia (see below). Both taxa produce isidia, but in S. narinioana, they are concentrated along the thallus margins and horizontally orientated, while in S. aymara, they are laminal and upright. Moreover, sparse, submarginal apothecia, absent in S. aymara, were observed in S. narinioana. Cilia are absent in both taxa, but in S. narinioana, the white tomentum projects beyond the edge of the lobes and resembles cilia. The two species also differ in the abundance of cyphellae, which are more densely arranged in S. narinioana.

The presence of isidia is also characteristic for S. isidiokunthii B. Moncada & Lücking and S. weigelii, amongst other similar species (Moncada 2012). However, isidia in these species are mainly marginal and differ in colour. In S. aymara the isidia are grey, in S. isidiokunthii, greenish-brown to brown and in S. weigelii, blackish-brown. Moreover, the latter taxa are characterised by thalli larger than S. aymara, up to 10–15 cm in diam. Differences were also observed in the structure and colour of the lower surface. In S. isidiokunthii, it is uneven, beige to dark brown, while in S. weigelii, it is smooth to undulate, beige to red-brown (Moncada 2012; Moncada and Lücking 2012; Ossowska 2021). Additionally, S. isidiokunthii also produces laminal apothecia (Moncada and Lücking 2012). The medulla of both S. isidiokunthii and S. weigelii reacts with K, while in S. aymara, it is K negative.

The small size of the thalli, the presence of isidia and the absence of apothecia is also characteristic of S. viviana A. Suárez & Lücking. However, this taxon has a dark brown, scrobiculate to faveolate upper surface with cream-coloured maculae. Furthermore, the lower part is rugose to undulating, rather than ridged-veined as in S. aymara. The medulla of S. viviana is K+ orange-yellow and the cyphellae are K+ yellow. The latter species is known from Colombia and Costa Rica (Moncada 2012; Suárez and Lücking 2013; Moncada et al., unpub.). Sticta aymara and S. viviana are phylogenetically only distantly related (Fig. 1; Suppl. material 3: Fig. S1).

Differing from S. pseudoimpressula in the predominantly bicellular spores and the absence of secondary tomentum and the K+ violet (instead of carmine-red) reaction of the apothecial atraquinone.

Figure 4. 

Morphology of Sticta bicellulata (holotype) A enlarged part of thallus showing pitted to rugose upper surface and laminal apothecia B lower surface C enlarged part of lower surface of the thallus D apothecia with hirsute margins and cilia at the lobe margins E tomentum and cyphellae F ascus with 1-septate ascospores. Scale bars: 1 mm (A–E); 10 μm (F).

Bolivia. Dept. La Paz; Prov. Franz Tamayo, Parque Nacional y Área Natural de Manejo Integrado Madidi, near Keara Bajo, 14°41'59"S, 69°04'34"W, elev. 3290 m, open area with shrubs and scattered trees, Ceja de Monte Inferior (Altimontano), on shrubs, 17 Nov 2014, M. Kukwa 14859 (holotype UGDA, isotype LPB).

Primary photobiont cyanobacterial (Nostoc). Stipe absent. Thallus irregular to suborbicular, up to 10 cm diam., moderately branched, with 3–5 branches per 5 cm radius, branching polytomous; lobes laciniate to flabellate, adjacent, involute to weakly canaliculate, with obtuse to truncate, plane to revolute apices and their margins entire, slightly thickened; lobe internodes (3–)6–8(–20) mm long, (4–)7–10(–13) mm broad; thallus coriaceous. Upper surface pitted to shallowly scrobiculate to rugose, light brown with darker apices in the herbarium, shiny, with the marginal line in the same colour; surface glabrous, without papillae and pruina, without maculae; marginal cilia present, about 0.5 mm, abundant to scarce, white to golden brown, agglutinated. Apothecia scarce, laminal, dispersed, subpedicellate, with pronounced invagination on lower side, up to 2.5 mm diam.; disc orange-brown (in young apothecia) to brown or greenish (in older apothecia) due to the presence of pruina, along the margin with an orange pigment; margin hirsute, with white to golden brown hairs. Vegetative propagules absent. Lower surface uneven, beige to light brown; primary tomentum dense to the margin, thick, but thinner towards the margin, spongy, soft, white to dark brown often with brown tips; secondary tomentum absent. Rhizines absent. Cyphellae 1–10 per cm² towards the thallus centre and 21–40 per cm² towards the margin, abundant, scattered, rounded to irregular, urceolate with wide pore, prominent, remaining below the level of the primary tomentum, with the margin raised and involute, white to brown coloured, without or with tomentum at the base; pore (0.25–)0.5–1(–1.5) mm diam.; basal membrane pruinose in the appearance, white, K– to K+ yellow, C–, KC–, Pd–. Medulla compact, white with yellow spots, K+ pale yellow, C–, KC–, Pd–. Apothecial margin (ring around disc) and epihymenium K+ violet. No substances detected by TLC in the thallus, unidentified anthraquinone in the apothecia.

Upper cortex paraplectenchymatous, 35–50 μm thick, consisting of 3–4 layers of cells 5–16 μm diam. (with smaller cells in outside parts of the cortex), their walls 1.5–3.5 μm thick and their lumina rounded to isodiametric, 4–15 μm diam. Photobiont layer 40–80 μm thick, its cells 5–10 μm diam. Medulla 35–50 μm thick, its hyphae 5 μm broad, without crystals. Lower cortex paraplectenchymatous, 25–35 μm thick, with 2–3 cell layers; cells 7–13 μm diam., their walls 2.5–5 μm thick. Hairs of lower primary tomentum 100–250 μm long, in fascicles of more than 20 when mature, simple to rarely branched hyphae, 5–6 μm broad, septate with free apices. Cyphella cavity up to 100 μm deep; cells of basal membrane loosely packed consisting of cells, without papillae or very rarely, with one papillae. Apothecia biatorine, up to 100–250 μm high, without a peduncle; excipulum 80–100 μm broad, laterally with projecting hairs, hairs simple, up to 110 μm long or in groups up to 300 μm long, hairs 4–6 μm broad, thick-walled, septate. Hymenium 100–112 μm high; epihymenium 12.5–20 μm high, orange-brown, with orange granules crystals, with thin gelatinous upper layer. Asci 6–8-spored, ascospores broadly fusiform, 1(–3)-septate, 30–41 × 9–12 μm.

The species is known from the Parque Nacional y Área Natural de Manejo Integrado Madidi, a protected area in the Department La Paz. It was found epiphytic at an elevation of 3290 m.

The epithet refers to the predominance of bicellular spores.

Bolivia. Dept. La Paz; Prov. Franz Tamayo, Parque Nacional y Área Natural de Manejo Integrado Madidi, near Keara Bajo, 14°41'59"S, 69°04'34"W, elev. 3290 m, open area with shrubs and scattered trees, Ceja de Monte Inferior (Altimontano), on shrubs, 17 Nov 2014, M. Kukwa 14863 (LPB, UGDA).

Sticta bicellulata is similar to S. pseudoimpressula (another species described below), but the main discriminating character in S. bicellulata is the septation of the ascospores, which are predominantly bicellular (only very few are 3-septate whereas in S. pseudoimpressula, only young ascospores are bicellular. Both taxa have irregular to suborbicular thalli, with laciniate to flabellate lobes, but the lobe apices in S. bicellulata are obtuse to truncate vs. orbicular in S. pseudoimpressula. Furthermore, S. bicellulata has a paler upper surface than S. pseudoimpressula. In both species, marginal cilia are present, but in S. bicellulata, they are agglutinated, white to golden brown vs. fasciculated, light brown to golden brown in S. pseudoimpressula. Apothecia in S. bicellulata are sparse in contrast to the abundant apothecia in S. pseudoimpressula. They also differ in the colour of the disc, which in both species is covered by a pruina. The margin and epihymenium react with K in both taxa, but in S. bicellulata the reaction is K+ violet and in S. pseudoimpressula K+ carmine-red, suggesting the presence of different anthraquinones. The lower surface in both species is uneven, but in S. bicellulata, the tomentum is thick, becoming thinner towards the margin and a secondary tomentum is absent. Conversely, in S. pseudoimpressula, the primary tomentum is consistently thick and long, with a secondary tomentum present and with rhizines. The cyphellae in these two taxa are similar in shape, but in S. bicellulata, their margins are raised and involuted.

Remarkably, the taxa form a sister group relationship, denoting the presence of apothecial anthraquinones as a synapormorphy, although apparently, the two species diverged to the point that the anthraquinones are of a different nature, as indicated by their different K+ reaction. This character appears to be rare in Sticta, but may also have been overlooked, as it is only obvious in a close-up of the apothecium.

The clade formed by Sticta bicellulata and S. pseudoimpressula is closely related to S. sylvatica and S. peltigerella (Fig. 1; Suppl. material 3: Fig. S1). The latter two produce numerous isidia distributed over the entire surface of the thalli (Moncada 2012). Sticta sylvatica is widespread, occurring in Europe, North and South America (Hodkinson et al. 2014), whereas S. peltigerella appears to be a Colombian endemic (Moncada 2012).

Differing from S. andina in the green algal photobiont, the absence of vegetative propagules and the yellow medulla.

Figure 5. 

Morphology of Sticta carrascoensis (holotype) A, B upper surface with marginal and laminal apothecia C lower surface D apothecia with hirsute margins E tomentum, cyphellae and cilia at the lobe margin F basal membrane of cyphella with papillae. Scale bars: 1 mm (A–E); 10 μm (F).

Bolivia. Dept. Cochabamba; Prov. Carrasco, Parque Nacional Carrasco, Meruvia close to Monte Punku, 17°35'06"S, 65°14'54"W, elev. 3283 m, Podocarpus-Polylepis forest, Ceja de Monte Inferior (Altimontano), corticolous, 26 Nov 2014, M. Kukwa 15028 (holotype UGDA, isotype LPB).

Primary photobiont a green alga. Stipe absent. Thallus irregular to suborbicular, up to 30 cm diam., moderately branched, with 3–5 branches per 5 cm radius, branching pleurotomus; lobes laciniate to flabellate, interspaced to adjacent, involute, with their apices rounded and plane to involute and their margins entire, not thickened; lobe internodes (3–)6–9(–10) mm long, (3–)9–10(–12) mm broad; thallus coriaceous. Upper surface shallowly scrobiculate to rugose, yellow-brown to light brown, with darker apices in the herbarium, shiny; surface glabrous, without papillae, pruina and weakly maculate; marginal cilia present, brown, about 0.2 mm long, fasciculate. Apothecia abundant, marginal to laminal, dispersed to arranged, sometimes imbricate, subpedicellate, with pronounced invagination on lower side, up to 4 mm diam.; disc orange-brown (young apothecia) to red-brown (older apothecia), very shiny when young; margin crenate, hirsute, with dark brown hairs. Vegetative propagules absent. Lower surface somewhat ridged, yellow to dark brown towards the centre; primary tomentum dense to the margin, thick, thinner towards the margin, spongy, soft, pale to dark brown; secondary tomentum very scarce, up to 25 μm. Rhizines present, about 2 mm, brown with paler tips, fibrillose. Cyphellae 1–10 per cm² towards the thallus centre and 21–40 per cm² towards the margin, scattered, round to irregular, urceolate with wide pore, erumpent to prominent, remaining below the level of the primary tomentum, with the margin raised and involute, brown-coloured, without tomentum or with in the lower part; pore (0.2–)0.3–0.5(–0.6) mm diam.; basal membrane pruinose in the appearance, white to yellow, K– to K+ yellow, C–, KC–, Pd–. Medulla compact, pale yellow to yellow, K+ lemon-yellow, C–, KC–, Pd–. No substances detected by TLC.

Upper cortex paraplectenchymatous, external part orange-brown, 40–60 μm thick, consisting of 6–7 cell layers with cells 5–10 μm diam. (with smaller cells in outside parts of the cortex), their walls 2–3 μm thick and their lumina rounded to isodiametric, 3–10 μm diam., up to 12 μm broad. Photobiont layer 25–35 μm thick, its cells 4–6 μm diam. Medulla 120–150 μm thick, its hyphae 1.5–4.5 μm broad, without or with yellow crystals. Lower cortex paraplectenchymatous, 25–30 μm thick, with 3 cell layers; cells 6–16 μm diam., their walls 1–3 μm thick. Hairs of lower primary tomentum up to 1 mm long, in fascicles up to 12, forming intricate mass in the dense part of tomentum, hyphae unbranched, 5–7 μm broad, septate with free apices. Cyphella cavity up to 250 μm deep; loosely packed cells of basal membrane sometimes with one papilla. Apothecia biatorine, up to 1 mm high, without or very short stipe, about 300 μm long; excipulum up to 100 μm broad, laterally with projecting hairs, simple or in groups, hyphae rarely branched, up to 180 μm long. Hymenium up to 100 μm high; epihymenium up to 25 μm high, pale brown, without gelatinous upper layer. Asci 6–8-spored, ascospores fusiform, 1–3-septate, 26–33 × 7–9 μm.

Sticta carrascoensis was collected at a single locality in the Parque Nacional Carrasco in the Department Cochabamba, at an altitude of 3283 m. The specimen grew on the bark of a tree in Podocarpus-Polylepis forest.

The name refers the type locality.

Sticta carrascoensis is phylogenetically close to S. andina, although this relationship is not supported (Fig. 1; Suppl. material 3: Fig. S1). The latter differs by its cyanobacterial photobiont and the formation of isidia and/or phyllidia, not observed in S. carrascoensis. The thalli in S. andina are smaller (up to 15 cm in diam.), the margins of the lobes are sparsely covered by cilia and the medulla is white to cream, sometimes with yellowish patches and reacts K+ yellow (Moncada et al. 2021a). In S. carrascoensis, the medulla is distinctly yellow and reacts K+ lemon-yellow. Sticta andina is widespread in South America and, so far, has been confirmed from numerous localities from Brazil, Colombia and Ecuador and also from Costa Rica, Mexico and in Hawaii (Moncada et al. 2014a, b, 2020; Widhelm et al. 2018). Thus far, only one collection of S. carrascoensis is known, but it is well-developed and phylogenetically unique, with no close supported relative.

Differing from other Sticta species in having a stipe, up to 1 cm long, a palmate thallus with abundant, submarginal to laminal apothecia, with the primary tomentum absent in the marginal parts of the thallus and a secondary tomentum present.

Figure 6. 

Morphology of Sticta catharinae (holotype) A upper surface with submarginal to laminal apothecia B lower surface C lower surface showing venation D enlarged part of the lower surface with tomentum and cyphellae E apothecia with margin tomentum and hairs and lobe margin with cilia F stipe. Scale bars: 1 mm.

Bolivia. Dept. La Paz; Prov. Nur Yungas, Parque Nacional y Área Natural de Manejo Integrado Cotapata, near Urpuma colony, 16°13'20"S, 67°52'34"W, elev. 1989 m, Yungas montane forest, 30 June 2010, A. Flakus 17263 & P. Rodriguez-Flakus (holotype KRAM, isotype LPB).

Primary photobiont cyanobacterial (Nostoc). Stipe present, up to 1 cm long. Thallus palmate, up to 10 cm diam., moderately branched, with 3–5 branches per 5 cm radius, branching anisotomous to pleurotomous; lobes suborbicular to flabellate, interspaced to adjacent, involute, with their apices rounded and plane and their margins entire to sinuous, not thickened; lobe internodes (4–)6–15(–20) mm long, (6–)10–10(–20) mm broad; thallus coriaceous. Upper surface smooth to shallowly rugose in some parts, brown-grey, darker in the margins, shiny; surface glabrous, without papillae and pruina, without maculae; marginal cilia abundant, agglutinated to fasciculated, dark brown with pale tips, up to 0.5 mm long. Apothecia abundant, principally submarginal to laminal, dispersed, subpedicellate, sessile, up to 1.5 mm diam.; disc reddish-brown, shiny (in young apothecia) to matt (in older); margin entire to weakly crenate, excipulum hairs few to dense. Vegetative propagules absent. Lower surface folded to distinctly ridged and forming a reticulate pattern especially towards the margins, yellowish-brown to brown towards the centre; primary tomentum scarce, absent in the marginal part of the thallus, fasciculate, soft, golden brown; secondary tomentum present, arachnoid, up to 25 μm. Rhizines absent. Cyphellae 1–20 per cm² towards the thallus centre and 21–40 per cm² towards the margin, scattered, irregular to elongate or rounded, urceolate with narrow to wide pore, prominent, on the same level as the primary tomentum or below, with the margin raised and involute to raised and involute-circinate, brown coloured, with or without tomentum; pore (0.25–)0.5–1(–2) mm diam.; basal membrane smooth, white, K+ yellowish, C–, KC–, Pd–. Medulla loose, white, K± yellowish, C–, KC–, Pd–. No substances detected by TLC.

Upper cortex paraplectenchymatous, 20–50 μm thick, differentiated into two cellular layers, the upper layer consisting of 1–2 layers of cells, with cells 5–6 μm diam., their walls 1–2 μm thick and their lumina rounded to isodiametric, 4–6 μm diam.; the lower layer of cortex 2–3 layers of cells, with cells 8–15 μm diam., their walls 1–2.5 μm thick and their lumina rounded to isodiametric, 3–5 μm diam. Photobiont layer 20–60 μm thick, its cells 6–12 μm diam. Medulla 100–220 μm thick, its hyphae 3–5.5 μm broad, without crystals. Lower cortex paraplectenchymatous, 20–50 μm thick, with 2–4 cell layers; cells 8–17 μm diam., their walls 2–4 μm thick. Hairs of lower primary tomentum up to 220 μm long and 3–5 μm broad, in groups to rarely simple, in fascicles up to 15, hyphae unbranched, septate, with free apices forming a brush-like head. Cyphella cavity up to 120 μm deep; membrane of cells densely packed, cells of basal membrane with 2–4 papillae. Apothecia biatorine, ca. 500 μm high, without distinct stipe; excipulum up to 120 μm broad, without or with projecting hairs, simple to fasciculate. Hymenium 100–120 μm high, hyaline, but K+ yellow; epihymenium ca. 10 μm high, orange-brown, K+ orange intensifying, without gelatinous upper layer. Asci 6–8-spored, ascospores fusiform, 2–4-septate, 31–37 × 8–9 μm.

Sticta catharinae is known only from the type locality in Yungas forest in the Department La Paz.

The new species is named to honour our late friend and teacher, Polish botanist Dr Katarzyna Żółkoś, for her contributions to the conservation of nature.

Sticta catharinae is the only species amongst those newly described here that is characterised by the presence of a stipe supporting the thallus. Morphologically, this taxon is similar to S. aff. caliginosa D. J. Galloway and the cyanomorph of S. neopulmonarioides B. Moncada & Coca, which share the stipe and the palmate thallus. However, in S. aff. caliginosa and S. neopulmonarioides, no apothecia are known, whereas vegetative propagules in the form of isidia or phyllidia and lobules are present (Galloway 1997; Moncada 2012; Moncada et al. 2013a). In addition, these taxa differ in the shape of the lobes and the presence of marginal cilia. In S. aff. caliginosa, the lobes are ligulate to flabellate, with their apices rounded to obtuse and with cilia being sparse to absent (Moncada 2012). In contrast, S. neopulmonarioides has flabellate lobes with irregular apices, without cilia (Moncada et al. 2013a). Sticta neopulmonarioides is widely distributed in Colombia, while S. aff. caliginosa is a rare taxon in that country (Moncada 2012; Moncada et al. 2013a, 2014b).

The new species is closely related to S. fuliginoides (Fig. 1; Suppl. material 3: Fig. S1), a morphologically disparate taxon with broad lobes producing laminal isidia (Magain and Sérusiaux 2015). It is also phylogenetically quite distinctive from the latter, with a total of 16 substitutions and nine indels in the ITS (Suppl. material 2: File S1), warranting its formal description, based on a single collection only.

Differing from S. impressula in the presence of imbricately arranged and grouped apothecia with orange-yellow pruina along the margin of the disc, reacting K+ carmine-red and in the presence of a secondary tomentum.

Figure 7. 

Morphology of Sticta pseudoimpressula (holotype) A, C upper surface with laminal apothecia B, D lower surface E group of imbricately arranged apothecia with hirsute margins F tomentum and cyphellae. Scale bars: 1 mm.

Bolivia. Dept. La Paz; Prov. Franz Tamayo, Área Natural de Manejo Integrado Nacional Apolobamba, near Río Pelechuco, below Pelechuco close to new road to Apolo, 14°46'39"S, 69°00'35"W, elev. 2250 m, lower montane Yungas cloud forest, corticolous, 16 Nov 2014, M. Kukwa 14750 (holotype UGDA, isotype LPB).

Primary photobiont cyanobacterial (Nostoc). Stipe absent. Thallus irregular to suborbicular, up to 10 cm diam., moderately branched, with 3–5 branches per 5 cm radius, branching polytomous; lobes laciniate to flabellate, adjacent, plane, with their apices orbicular and revolute to involute and their margins entire to crenate, not thickened; lobe internodes (4–)7–10(–15) mm long, (4–)7–9(–15) mm broad; thallus coriaceous. Upper surface pitted to scrobiculate to rugose towards the centre, yellowish-brown with darker apices in the herbarium, with marginal line in the same colour, shiny; surface glabrous, without papillae and pruina, without maculae; marginal cilia present, abundant, fasciculate, light brown to dark brown, about 0.5 mm. Apothecia abundant, laminal, dispersed, often imbricately arranged and grouped, subpedicellated, with pronounced invagination on lower side, up to 3.5 mm diam.; disc red-brown to brown, sometimes greenish-yellow due to the presence of pruina, shiny; margin entire to crenate and hirsute, with white hairs and orange-yellow pruina. Vegetative propagules absent. Lower surface uneven, beige to dark brown towards the centre; primary tomentum dense to the margin, thick (long), spongy, soft, grey-brown to black with paler tips; secondary tomentum present, but sparse, pubescent, up to 30 μm long. Rhizines sparse, black, up to 0.5 mm. Cyphellae 1–20 per cm² towards the thallus centre and 41–60 per cm² towards the margin, scattered, irregular, cupuliform to urceolate with wide pore, prominent, below the level of the primary tomentum, with the margin erect, cream to brown coloured, without or with tomentum in the lower half; pore (0.5–)0.6–1.3(–2.5) mm diam.; basal membrane pruinose in the appearance, white to pale beige in older part of thallus; K– to K+ pale yellow, C–, KC–, Pd–. Medulla compact, beige-white, K+ yellow, C–, KC–, Pd–. Apothecia margin (ring around disc) and epihymenium K+ carmine-red. No substances detected by TLC, unidentified anthraquinone in apothecia.

Upper cortex paraplectenchymatous, 20–40 μm thick, consisting of 2–3 cell layers with cells 6–22 μm diam. (with smaller cells in outside parts of the cortex), their walls 1–2 μm thick and their lumina rounded to isodiametric, 5–21 μm diam. Photobiont layer 60–110 μm thick, its cells 7–18 μm diam. Medulla 30–100 μm thick, its hyphae 3–5 μm broad, without crystals. Lower cortex paraplectenchymatous, 25–40 μm thick, with 3–4 cell layers; cells 8–18 μm diam., their walls 2–4 μm thick. Hairs of lower primary tomentum up to 1000 μm long, in fascicles of more than 20, hyphae unbranched to rarely branched, septate with flexuous apices. Cyphella cavity 100–125 μm deep; cells of basal membrane loosely packed consisting of cells without papillae or very rarely one. Apothecia biatorine, up to 700 μm high, without distinct stipe; excipulum up to 125 μm broad, laterally with projecting hairs, in groups to rarely simple, up to 0.5 mm, 5–6 μm broad. Hymenium 80–110 μm high; epihymenium 20 μm high, orange, with pigment granules on the top, without gelatinous upper layer. Asci 6–8-spored, ascospores fusiform, 1–3-septate, 28–35 × 8.5–10 μm.

Sticta pseudoimpressula is an epiphytic species, found in Bolivia at one locality at an altitude of 2250 m in a lower montane Yungas forest in the Department La Paz.

The name refers to the similarity in morphology to Sticta impressula.

Bolivia. Dept. La Paz; Prov. Franz Tamayo, Área Natural de Manejo Integrado Nacional Apolobamba, near Río Pelechuco, below Pelechuco close to new road to Apolo, 14°46'39"S, 69°00'35"W, elev. 2250 m, lower montane Yungas cloud forest, corticolous, 16 Nov 2014, M. Kukwa 14752 (LPB, UGDA).

Sticta pseudoimpressula is similar to S. impressula (Nyl.) Zahlbr. Both species have a pitted to scrobiculate or rugose upper surface with abundant, laminal apothecia and the lobe margins with abundant, light brown cilia. The tomentum is dense to the margin in the latter (Moncada 2012). However, the two species are not closely related phylogenetically (Fig. 1; Suppl. material 3: Fig. S1): Sticta impressula is clustered in a neighbouring clade with S. brevior B. Moncada & Lücking and S. isidiokunthii. In contrast, S. pseudoimpressula shares a common ancestor with S. bicellulata, S. peltigerella and S. sylvatica. The differences between S. pseudoimpressula and S. bicellulata are discussed under the latter.

The morphological features that distinguish S. pseudoimpressula from S. impressula are the moderately-branched thalli and the laciniate to flabellate lobes. The apothecia in S. pseudoimpressula are often imbricately arranged and grouped and produced orange-yellow pruina along the disc margins and reacts K+ carmine-red. A secondary tomentum is present in S. pseudoimpressula, but absent in S. impressula. In addition, the cyphellae in S. impressula are rounded to angular and urceolate with a wide pore, erumpent to suprasessile and the margins raised to involute. The latter taxon is widely distributed in Colombia, where it grows at elevations between 1500 and 3800 m (Moncada 2012; Moncada et al. 2014b).

At first sight, S. pseudoimpressula can also be confused with S. brevior, but that taxon has smaller thalli with abundant apothecia, tomentose margins and the lower surface is undulating, creamy white to light brown (Moncada 2012; Moncada et al. 2013b). Sticta brevior is known from Colombia (Moncada et al. 2013b, 2014b).

Differing from S. aymara in the predominantly marginal and horizontally projecting isidia, the slightly projecting lower tomentum, giving the impression of marginal cilia, the absence of a secondary tomentum and the more densely arranged cyphellae.

Figure 8. 

Morphology and anatomy of Sticta narinioana (A Moncada & Lücking 7525 B–F Simijaca et al. 2044) A thallus in situ B lobe tip with apothecia C lobe margin with isidia D section through thallus E section through apothecium F ascospores. Scale bars: 10 mm (A); 1 mm (B, C); 50 μm (D); 100 μm (E); 10 μm (F).

Colombia. Dept. Nariño; Laguna de la Cocha, Reserva el Encanto Andino, sendero al páramo, 01°04'12.3"N, 77°07'38.1"W, elev. 2810 m, andine forest, epiphytic on tree trunk, 24 Oct 2013, B. Moncada & R. Lücking 7614 (holotype UDBC, isotype B).

Primary photobiont cyanobacterial (Nostoc). Stipe absent. Thallus orbicular to irregular, up to 5 cm diam., moderately branched, with 2–5 branches per 5 cm radius, branching pleurotomous; lobes suborbicular to flabellate, interspaced to adjacent, plane to undulate, with their apices rounded to somewhat truncate and revolute and their margins entire to sinuous, not thickened; lobe internodes (3–)5–10 mm long, (3–)5–8(–10) mm broad; thallus subcoriaceous. Upper surface smooth to uneven-rugose towards the centre, greyish-brown when fresh, light to medium yellowish-brown with darker apices in the herbarium, somewhat shiny; surface glabrous, without papillae, pruina or maculae; true marginal cilia absent, but lower tomentum partly projecting beyond the margins and resembling cilia. Apothecia rare to moderately abundant, submarginal, dispersed, subpedicellate, with invagination on lower side, up to 2 mm diam.; disc orange-brown, somewhat shiny; margin densely hirsute, with white hairs. Vegetative propagules present, abundant, in the form of isidia, predominantly marginal, becoming branched and somewhat coralloid, terminally cylindrical, but with the base flattened, more or less obliquely orientated, up to 0.1 mm long and 0.03 mm broad, dark brown and darker than the thallus, shiny. Lower surface somewhat uneven, beige, somewhat darker towards the centre; primary tomentum dense and comparatively thick to the margin, fasciculate, soft, whitish to cream-coloured or pale brownish; secondary tomentum absent, except for the lower sides of the apothecia. Rhizines absent. Cyphellae frequent, 10–20 per cm² towards the thallus centre and 20–50 per cm² towards the margin, dense, rounded to somewhat irregular, urceolate with wide pore, erumpent, remaining below the level of the primary tomentum, with the margin raised and involute, whitish to cream-coloured, with or without tomentum; pore 0.3–1.5 mm diam.; basal membrane ± smooth, white, K–, C–, KC–, Pd–. Medulla compact, cream, K–, C–, KC–, Pd–. No substances detected by TLC.

Upper cortex paraplectenchymatous, 20–40 μm thick, consisting of 2–4 layers of cells 8–15 μm diam. with thin, hyaline walls and one layer of smaller cells with thicker, yellowish-brown walls. Photobiont layer 20–30 μm thick, its cells 5–10 μm diam. Medulla 50–100 μm thick, its hyphae 2.5–5 μm broad, without crystals. Lower cortex paraplectenchymatous, 15–30 μm thick, consisting of 2–3 cell layers; cells 5–10 μm diam., their walls 1–2 μm thick, but lowermost walls much thicker. Hairs of lower primary tomentum 100–200 μm long, in fascicles of 5–20, hyphae simple, septate with partly intertwined apices. Cyphella cavity up to 150 μm deep; cells of basal membrane without papillae or with one papillae. Apothecia biatorine, up to 500 μm high, without distinct stipe; excipulum up to 100 μm broad, laterally with projecting hairs in groups, up to 0.5 mm long and 4–5 μm broad. Hypothecium 60–80 μm high, light yellowish-green. Hymenium 80–110 μm high; epihymenium 15–20 μm high, orange, with pigment granules, without gelatinous upper layer. Asci 8-spored, ascospores fusiform, 1-septate, 35–40 × 7–8 μm.

Sticta narinioana is known as epiphyte from two localities of well-preserved (sub-)andine forest in southern Colombia.

The epithet honours Antonio Amador José Nariño (y Álvarez del Casal) (1765–1823), one of the critical architects of the independence of Colombia and after whom the Department of Nariño was named.

Colombia. Dept. Nariño; Laguna de la Cocha, Reserva el Encanto Andino, sendero al páramo, 01°04'12.3"N, 77°07'38.1"W, 2810 m elev., andine forest, epiphytic on tree trunk, 24 October 2013, B. Moncada & R. Lücking 7525 (B, UDBC). Boyacá: Garagoa, Vereda Ciénaga, Valvanera, Reserva Privada El Secreto; 12 June 2014, D. Simijaca et al. 2044 (B, UDBC).

Sticta narinioana is closely related to the Bolivian S. aymara described above. Both taxa are cyanobacterial, isidiate species, but S. aymara has largely laminal isidia and the lower tomentum is not projecting to resemble cilia. Additionally, the cyphellae are less densely arranged and smaller.