ITALIC 8.0

Placidiopsis cinerascens (Nyl.) Breuss

Plant Syst. Evol., 148: 315, 1985. Basionym: Endocarpon cinerascens Nyl. - Bot. Not.: 160, 1853.

Synonyms: Catapyrenium circinatum (Bagl.) Jatta; Catapyrenium grappae (Beltr.) Jatta; Catapyrenium pisanum (Bagl.) Jatta; Dermatocarpon baumgartneri (Zahlbr.) Zahlbr.; Dermatocarpon cinerascens (Nyl.) Zahlbr.; Endocarpon grappae (Beltr.) Garov.; Endocarpon pervirescens Nyl.; Placidiopsis baumgartneri Zahlbr.; Placidiopsis circinata Bagl.; Placidiopsis dalmatica Servít; Placidiopsis grappae Beltr.; Placidiopsis pisana Bagl.; Placidium cinerascens (Nyl.) Arnold; Placocarpus cinerascens (Nyl.) Trevis.; Verrucaria cinerascens (Nyl.) Nyl.

Distribution: N - Ven (Breuss 1996b), Piem (Gheza & Nascimbene 2024). C - Tosc (Breuss 1996b), Sar (Breuss 1996b). S - Pugl (Breuss 1996b), Bas (Breuss 1996b, Puntillo 1996, Puntillo & Puntillo 2004, Prieto & al. 2010, Potenza & al. 2010), Si (Nimis & al. 1994, Breuss 1996b, Caniglia & Grillo 2005, 2006, Cataldo & Minissale 2013).

Description: Thallus squamulose, the squamules rounded to lobulate, 1-3 mm broad, 0.15-0.35 mm thick, flattened to weakly convex, smooth, scattered to contiguous, sometimes weakly overlapping at margins, adpressed to the substratum, greenish grey to brownish grey, sometimes pruinose, matt; lower surface pale, attached by 3-4 μm thick, colourless rhizohyphae. Upper cortex 15-25 μm thick, pseudoparenchymatous, covered with a 10-30 μm thick epinecral layer; medulla poorly developed, of mostly globose cells; lower cortex absent or poorly developed and consisting of 1-3 layers of isodiametrical cells. Perithecia frequent, laminal, immersed in the squamules, slightly pyriform to globose, up to 0.3 mm across, without involucrellum. Exciple initially colourless, then brownish, darker only around the ostiole, of tangentially arranged, elongate cells; periphyses present around the ostiole, 20-30 x 2.5-3 μm, the terminal cells somewhat enlarged, interascal filaments absent; hymenial gel hemiamyloid. Asci 8-spored, narrowly clavate, thin-walled, apically slightly thickened, with a small ocular chamber, K/I-, 55-65 x 11-16 μm. Ascospores 1-septate, often slightly constricted at septum, hyaline, broadly ellipsoid to subclavate, thin-walled, (13-)15-19(-21) x 5.5-8 μm. Photobiont chlorococcoid (Diplosphaera). Spot tests: cortex and medulla K-, C-, KC-, P-, UV-. Chemistry: without lichen substances.

Note: on clayey, somewhat calciferous but often superficially decalcified soil in grasslands and garrigues below the montane belt; in Italy this species seems to behave as a vicariant of the submediterranean P. custnani in the Mediterranean belt. See also note on P. tenella.

Growth form: Crustose

Substrata: soil, terricolous mosses, and plant debris

Photobiont: green algae other than Trentepohlia

Reproductive strategy: mainly sexual

Commonnes-rarity: (info)

Alpine belt: absent

Subalpine belt: absent

Oromediterranean belt: absent

Montane belt: absent

Submediterranean belt: extremely rare

Padanian area: absent

Humid submediterranean belt: very rare

Humid mediterranean belt: rare

Dry mediterranean belt: rare

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

Index Fungorum GBIF

P.L. Nimis CC BY-SA 04

TSB 24493 topotype of Placidiopsis grappae

P.L. Nimis; Owner: Department of Life Sciences, University of Trieste

Herbarium: TSB (24493)
2003/03/06
topotype of Placidiopsis grappae