Protoblastenia violacea Pykälä & Myllys, 2025

Pykälä, Juha & Myllys, Leena, 2025, Unexpected species richness of the lichen genus Protoblastenia (Lecanorales, Psoraceae) in Finland, MycoKeys 124, pp. 193-226 : 193-226

Protoblastenia violacea Pykälä & Myllys sp. nov.

Fig. 5 C

Diagnosis.

Differs from most Protoblastenia species with violet hypothecium in having a thick hypothecium and from P. westbergii in having less densely occurring apothecia and smaller spores.

Type.

Finland • Enontekiön Lappi, Enontekiö, Porojärvet, Toskalharji, Toskalpahta , fell, dolomite rock outcrop, beneath SW-facing wall, on dolomite pebbles, 800 m a. s. l., 69°11'N, 21°30'E, 4 August 2011, J. Pykälä 43524 ( H 9250947 – holotype, GenBank accession number: PV 766713 ) .

Description.

Thallus white, grey or pale brown, rimose to areolate, areoles 0.15–0.4 mm, ca. 0.01–0.15 mm thick, K-, C-, UV-, algal cells 6–10 μm. Apothecia orange, 0.3–1.0 mm, convex to mainly strongly convex, superficial, high; ca. 20–40 apothecia / cm 2, sometimes forming clusters of smaller apothecia on surface of old apothecia. Epihymenium orange-brown, 12–14 μm thick, K + violet. Hymenium 60–80 μm thick. Hypothecium purple, orange-red to red-violet, ca. 100–280 μm thick. Paraphyses ca. 2–2.5 (– 3) μm thick, apex not thickened to slightly thickened, often branching. Ascospores 0 - septate, (6.3 –) 7.9–9.2 – 10.5 (– 12.7) × (3.7 –) 4.2–4.6 – 5.1 (– 5.6) μm (n = 52).

Habitat and distribution.

The three specimens are known from the calcareous Toskalharji fell (NW Finland), all from dolomite pebbles. Companion species include Farnoldia jurana and Lecidella stigmatea .

Etymology.

The name refers to the violet hypothecium of the species.

Notes.

The species is related to P. pseudoterricola and P. terricola , which have mainly brown apothecia and broader spores. Protoblastenia violacea differs from P. siebenhaariana in having more densely occurring apothecia (only ca. 1–10 apothecia / cm 2 in P. siebenhaariana ; Kainz and Rambold (2004)), slightly smaller apothecia and a thinner hymenium. Protoblastenia westbergii has more densely occurring apothecia and larger spores.

Other specimens examined.

Finland • Enontekiön Lappi, Enontekiö, Porojärvet, Toskalharji, Toskalpahta , fell, SW-slope, on dolomite pebbles, 765 m a. s. l., 69°11'N, 21°29'E, 1. 8. 2011, J. Pykälä 43015 ( H) ; • Enontekiö, Porojärvet, Toskalharji, 1.2 km NE of Toskaljärvi , fell, SW-slope, gentle E-slope, Dryas heath, on dolomite pebbles, 875 m a. s. l., 69°11'N, 21°30'E, 5. 8. 2011, J. Pykälä 43605 ( H) .

Figures

Figure 5. A. Protoblastenia saanaensis (holotype); B. P. timdalii (holotype); C. P. violacea (holotype); D. P. westbergii (holotype). Scale bars: 0.5 mm.