ITALIC 8.0

Verrucaria pachyderma (Arnold) Arnold

Verh. zool.-bot. Ges. Wien, 30: 146, 1880.. Basionym: Verrucaria chlorotica var. pachyderma Arnold - Verh. zool.-bot. Ges. Wien, 22: 286, 1872.

Synonyms: Verrucaria pissina Nyl.

Distribution: N - TAA (Nascimbene & al. 2022).

Description: Thallus crustose, episubstratic, subgelatinous when wet, mostly continuous, 40-200 μm thick, smooth, dull or slightly glossy, dark grey-green to blackish, sometimes with a brownish tinge, rarely delimited by a thin dark prothallus. Cortex weakly defined, with a dull green to brown-black pigment (lacking in shade-forms); algal layer paraplectenchymatous, 50-80 μm thick; medulla poorly developed, with oil cells and sometimes with a dilute brown pigment, but without a black basal layer. Perithecia immersed in thallus, not or only slightly projecting, the apex visible as a small, grey to black dot or ring. Involucrellum reddish brown and K+ grey, from thin and appressed to apex of exciple to conical and spreading, sometimes reaching base-level and laterally spreading; exciple 0.16-0.2(-0.35) mm across, the wall colourless except around the ostiole; hamathecium of up to 20 μm long periphysoids, interascal filaments absent; hymenial gel hemiamyloid, I+ red (I+ blue at very low concentrations of I), K/I+ blue. 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, 45-50 x 10-15 μm. Ascospores 1-celled, hyaline, ellipsoid to oblong-ellipsoid, (15-)17-22(-23.5) x 6-8(-9) μm, (1.9-)2.2-3(-3.2) times as long as wide, with a thin gelatinous perispore best visible in fresh material. Photobiont chlorococcoid, the cells arranged in vertical columns. Spot tests: K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.

Note: a freshwater species of periodically submerged siliceous rocks in upland areas, also known from the British Isles, Scandinavia, Corsica and the Austrian and Swiss Alps. For further details see Thüs & Schultz (2009), Orange (2013b), Krzewicka (2012), and Orange & al. (2023).

Growth form: Crustose

Substrata: rocks

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

Periodically submerged (e.g. in creeks)

Commonnes-rarity: (info)

Alpine belt: extremely rare

Subalpine belt: very rare

Oromediterranean belt: absent

Montane belt: very 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

DOLICHENS

Courtesy Danièle et Olivier Gonnet - Source: https://www.afl-lichenologie.fr/Photos_AFL/Photos_AFL_V/Texte_V/Verrucaria_pachyderma.htm

France, 24/11/2011 - Asco, sous le lac d’Argent, alt. 2100 m - Corse

Courtesy Danièle et Olivier Gonnet - Source: https://www.afl-lichenologie.fr/Photos_AFL/Photos_AFL_V/Texte_V/Verrucaria_pachyderma.htm

France, 24/11/2011 - Asco, sous le lac d’Argent, alt. 2100 m - Corse

Courtesy Danièle et Olivier Gonnet - Source: https://www.afl-lichenologie.fr/Photos_AFL/Photos_AFL_V/Texte_V/Verrucaria_pachyderma.htm

France, 24/11/2011 - Asco, sous le lac d’Argent, alt. 2100 m - Corse

Courtesy Danièle et Olivier Gonnet - Source: https://www.afl-lichenologie.fr/Photos_AFL/Photos_AFL_V/Texte_V/Verrucaria_pachyderma.htm

France, 24/11/2011 - Asco, sous le lac d’Argent, alt. 2100 m - Corse

Felix Schumm - CC BY-SA 4.0

[ABL48674], Brazil, Bahia, Itamarajú, Monte Pascoal, sacred pool on wet siliceous rock in Atlantic tropical rain forest. 16°53'08'' S, 39°24'30'' W, 100 m. Leg. M. Cáceres & A. Aptroot (no 48674), 17.02.2019, det. A. Aptroot 2019. - Spores simle, hyaline, 15 x 6 μm.

Zschacke, H. (1934) Epigloeaceae, Verrucariaceae und Dermatocarpaceae. In: Dr. L. Rabenhorst‘s Kryptogamen-Flora, Band 9, Abt. 1, Teil 1. Akademische Verlagsgesellschaft, Leipzig, 695 pp. - Public Domain

Source: Servít M. 1954a. Lichenes familiae Verrucariacearum. Prag, 249 pp.