ITALIC 8.0

Verrucaria hakulinenii Pykälä & Myllys

in Pykälä & al., Lichenologist, 56, 5: 264, 2024.

Synonyms:

Distribution: N - Ven (Pistocchi & al. 2026).

Description: Thallus crustose, thinly episubstratic, c. 0.05-0.1 mm thick, continuous, rimose to cracked-areolate, pale to medium green, sometimes with a brownish hue, turning pale brownish grey in the herbarium, the areoles, when developed, 0.2-0.8 mm wide; prothallus absent or very thin, brown. Cortex poorly developed, 10-30 μm thick, the cortical cells pale or brown; medulla not differentiated, the algal cells distributed throughout. Perithecia c. 110–200 per cm2, 0.13-0.26 mm across, half to 3/4 immersed, not leaving pits in the rock, often with a thin thalline cover except at the apex, the ostiole tiny, pale to dark, flat or depressed, c. 10-30 μm wide. Involucrellum reaching to base-level, c. 25-70 μm thick, appressed to the exciple or slightly diverging in lower part; exciple c. 0.15-0.24 mm across, the wall pale to medium brown, c. 22-25 μm thick; periphysoids branched, c. 17-25 x 1-2 μm, interascal filaments absent. Asci 8-spored, clavate, I-, fissitunicate, the wall thickened above, with an ocular chamber, dehiscent by extrusion of an endotunica to form a delicate rostrum, Verrucaria-type. Ascospores (17-)18-22(-25) x (6.5-)7.5-9.5(-11) μm. Photobiont chlorococcoid. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances

Note: a recently-described freshwater lichen from carbonatic rock in Finland (Pykälä et al. 2024) which is difficult to separate from other species in the V. hydrophila group by morphology alone. Its separation from V. floerkeana (which has not yet been sequenced, and for which Pykälä et al. recognized that the existing type material may be heterogenous) may require further study, but amongst those taxa for which reference sequences are available it is readily identified by its distinctive ITS-sequence.

Growth form: Crustose

Substrata: rocks

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

Pioneer species

Commonnes-rarity: (info)

Alpine belt: rare

Subalpine belt: very rare

Oromediterranean belt: absent

Montane belt: extremely rare

Submediterranean belt: absent

Padanian area: absent

Humid submediterranean belt: absent

Humid mediterranean belt: absent

Dry mediterranean belt: absent

pH of the substrata:

1

2

3

4

5

(info)

Solar irradiation:

1

2

3

4

5

(info)

Aridity:

1

2

3

4

5

(info)

Eutrophication:

1

2

3

4

5

(info)

Poleotolerance:

0

1

2

3

(info)

Altitudinal distribution:

1

2

3

4

5

6

(info)

Predictive model

Herbarium samples

DOLICHENS

Source: Pykälä J, Kantelinen A, Myllys L. Seven new species of Verrucaria from calcareous and siliceous rocks of Finland. The Lichenologist. 2024;56(5):259-272. doi:10.1017/S002428292400029X - CC BY-NC 4.0

Verrucaria hakulinenii (holotype). Scale bar: 0.5 mm

Source: Pykälä J, Kantelinen A, Myllys L. Seven new species of Verrucaria from calcareous and siliceous rocks of Finland. The Lichenologist. 2024;56(5):259-272. doi:10.1017/S002428292400029X - CC BY 4.0

holotype - Scale: 0.1 mm