Sticta montepunkuensis Ossowska, B. Moncada, Luecking & Kukwa, 2024

Ossowska, Emilia Anna, Moncada, Bibiana, Luecking, Robert, Flakus, Adam, Rodriguez-Flakus, Pamela, Olszewska, Sandra & Kukwa, Martin, 2024, Additional new species and new records of the genus Sticta (lichenised Ascomycota, lobarioid Peltigeraceae) from Bolivia, MycoKeys 105, pp. 21-47 : 21

Sticta montepunkuensis Ossowska, B. Moncada, Luecking & Kukwa sp. nov.

Fig. 5

Diagnosis.

Differing from other Sticta in the green algal photobiont, large thalli up to 30 cm diam., moderately branched, the upper surface scrobiculate to pitted or rugose, the margins of the apothecia crenate to verrucous and the presence of urceolate cyphellae with wide pores and scabrid, white to yellowish-white basal membrane.

Type.

Bolivia. Dept. Cochabamba; Prov. Carrasco, Parque Nacional Carrasco, Korikaza close to Monte Punku , 17°33'30"S, 65°16'32"W, elev. 2880 m, lower montane Yungas cloud forest, corticolous, 27 Nov 2014, M. Kukwa 15115 (holotype UGDA, isotype LPB) .

Description.

Primary photobiont green alga. Stipe absent. Thallus irregular, up to 30 cm diam., moderately branched, with 3-5 branches per 5 cm radius, branching pleurotomous to polytomous; lobes ligulate to laciniate, adjacent to interspaced, plane to involute, with their apices rounded to obtuse and plane and their margins entire, slightly thickened; lobe internodes (7-)10-18(-20) mm long, (5-)10-15(-18) mm broad; thallus coriaceous. Upper surface scrobiculate, pitted or rarely rugose, yellowish-brown and darkening towards the margins when dry, with brown marginal line, shiny; surface glabrous, without papillae, pruina and maculae; marginal cilia absent, but extension of the lower tomentum visible. Apothecia sparse, principally laminal, pedicellate, without pronounced invagination on lower side, up to 0.5 mm diam.; disc brown to red-brown, shiny; margin crenate to verrucous, light cream-brown. Vegetative propagules absent. Lower surface scrobiculate to undulate or faveolate, beige to dark brown towards the centre; primary tomentum dense, thick, but thinner towards the margin, fasciculate, soft, brown often with whitish tips; secondary tomentum present, pubescent to arachnoid. Rhizines sparse, irregularly dispersed, often in groups, fasciculate to barbate, brown with paler tips, up to 1 cm long. Cyphellae 41-60 per cm2 towards the thallus centre and more than 100 per cm2 towards the margin, scattered, rounded to slightly elongate, urceolate with wide pore, erumpent to sessile, remaining below the level of the primary tomentum, with the margin elevated and involute, brown-coloured, without tomentum; pore (0.3-)0.5-1.8(-2.5) mm diam.; basal membrane scabrid, white to yellowish-white. Medulla compact, white. Pycnidia present.

Upper cortex paraplectenchymatous, not distinctly differentiated into layers, 50-65 μm thick, consisting of up to nine cell layers, size of cells gradually decreasing towards the upper part, cells 5-17 × 4-14 μm, their walls 1-4 μm thick and their lumina rounded to isodiametric, 4-16 × 3-13 μm. Photobiont layer 30-50 μm thick, its cells 3.5-6 μm diam. Medulla up to 160 μm thick, its hyphae 3-4.5 μm broad, without crystals. Lower cortex paraplectenchymatous, 35-50 μm thick, with 3-4 cell layers; cells 9-17 × 8-13 μm, their walls 1-3 μm thick. Hairs of lower primary tomentum up to 220 μm long, in fascicles of 6-12, simple or often branched in upper parts, septate with free or interlocked apices, up to 8 μm wide; secondary tomentum up to 25 μm long. Cyphellae cavity up to 100 μm deep; cells of basal membrane usually without or rarely with up to three papillae. Apothecia biatorine, up to 700 μm high, with very short stipe; excipulum up to 250 μm broad, laterally with projecting hairs on the lower side, simple to branched. Hymenium up to 150 μm high; epihymenium up to 10 μm high, pale orange-brown, with gelatinous upper layer, ca. 4 μm high. Asci 6-8-spored, ascospores fusiform, 1(-3)-septate, 17-32 × 7-9 μm.

Secondary chemistry.

No lichen substances detected by TLC. All parts of thallus and apothecia K-, C-, KC-, P-.

Habitat and distribution.

Sticta montepunkuensis is known only from the type locality in Yungas cloud forest in Nacional Parque Carrasco, where it was collected on the bark of tree, at an elevation of 2880 m.

Etymology.

The name refers to the settlement Monte Punku in Parque Nacional Carrasco, near where the new species was found.

Notes.

The new species is related and morphologically similar to other green algal Sticta species, such as S. lobarioides and S. pseudolobaria (Fig. 1 ). All these taxa produce apothecia, but they are aggregated, with entire to verrucose margins in S. lobarioides , scattered with hairy to verrucous margins in S. pseudolobaria and, in S. montepunkuensis , they are subaggregated with crenate to verrucous margins. They also differ in the presence of a stipe (absent in S. montepunkuensis ) and the different sizes of the thalli (up to 20 cm in S. lobarioides and over 15 cm in S. pseudolobaria ). The upper surface in these species is faveolate rather than scrobiculate to pitted as it is in the new species and the primary tomentum is sparse over the entire surface, with no secondary tomentum (primary tomentum dense, secondary present in S. montepunkuensis ) ( Moncada 2012; Moncada et al. 2013a). For the differences between S. montepunkuensis and S. laciniata , see the general discussion above.

Other species known from Bolivia with green algae and large thalli include S. amboroensis and S. carrascoensis . The species differ in the structure of the tomentum. In S. amboroensis , it is spongy to dense, fasciculate, light to dark brown and sparse towards the margin ( Ossowska et al. 2022a). Sticta carrascoensis has a primary tomentum that is dense towards the margin like in S. montepunkuensis , but it is spongy, light to dark brown, whereas in the new species, it is fasciculate, brown with white tips. Sticta montepunkuensis also has more abundant cyphellae, i.e. 41-60 per cm2, towards the centre and more than 100 per cm2 towards the margin, whereas S. carrascoensis has 1-10 per cm2 and 21-40 per cm2, respectively and S. amboroensis 1-20 per cm2 and 21-40 per cm2 ( Ossowska et al. 2022a). Both, S. amboroensis and S. carrascoensis , have abundant apothecia, which are sparse in the new species and are submarginal in S. amboroensis and marginal to laminal in S. carrascoensis . Their apothecial margins are crenate to hirsute in both species, rather than crenate to verrucous as in S. montepunkuensis ( Ossowska et al. 2022a). All three species are not closely related (Fig. 1 ).

Figures

Figure 1. Best-scoring Maximum Likelihood tree of the Sticta target clade containing the new species from Bolivia (red) and the species new to Bolivia and phylogenetically confirmed from Bolivia (blue), based on the fungal ITS barcoding marker. Supported clades are thickened. For complete tree with individual support values, see Suppl. material 2.

Figure 5. Morphology of Sticta montepunkuensis (holotype) A, B upper surface C lower surface D apothecia with crenate to verrucous margins E, F lower tomentum with cyphellae and rhizines. Scale bars: 1 mm.