ITALIC 7.0

Leptogium terrenum Nyl.

Bull. Soc. Linn. Normandie, 2, 6, 1872.

Synonyms: Amphidium terrenum (Nyl.) Nyl.; Epiphloea terrena (Nyl.) Trevis.; Leptogium crozalsianum Harm.

Distribution: N - Lig (Watson 2014).

Description: Thallus subcrustose to subsquamulose, pale brown to yellowish grey, sometimes thin and inconspicuous, when well-developed formed by 0.4-1.2 mm broad and 0.1-0.2 mm thick, digitate-lobulate areoles radiating all around the apothecia; lower surface paler, attached by stout, pale rhizohyphae composed of 1-2 rows of isodiametrical cells. Thallus paraplectenchymatous throughout, of mostly anticlinally arranged, reticulate hyphae composed of elongated cells; lower cortex inconspicuous, with 1–2 rows of small isodiametrical cells. Apothecia frequent, without a distinct thalline margin, but often containing algal cells at the base of the proper margin, round, sessile, 0.5-1 mm across, with a reddish brown to brown-black, flat, smooth disc and a thin, smooth, persistent proper margin. Proper exciple distinct, colourless, composed of small cells, the basal parts often with clumps of photobionts; epithecium reddish brown; hymenium colourless, 100-125 µm high, K/I+ blue; paraphyses simple, straight, 1.5-2 μm thick, the apical cells slightly swollen; hypothecium colourless to pale brown. Asci 8-spored, narrowly clavate, the apex strongly thickened, the apical dome K/I+ pale blue, with a downwardly projecting K/I+ deep blue tubular structure. Ascospores submuriform, with 4-7 transverse septa and a few longitudinal septa, hyaline, narrowly ellipsoid, (15-)18-26(-38) x (5-)9-12(-14) µm. Photobiont cyanobacterial (Nostoc, the cells in short chains or in more or less rounded clumps). Spot tests: all negative. Chemistry: without lichen substances.

Note: on bare siliceous soil in Mediterranean grasslands and garrigues; probably much overlooked in Italy, but certainly not common, being known from a single station in Liguria.

Growth form: Crustose

Substrata: soil, terricolous mosses, and plant debris

Photobiont: cyanobacteria, filamentous (e.g. Nostoc, Scytonema)

Reproductive strategy: mainly sexual

Commonnes-rarity: (info)

Alpine belt: absent

Subalpine belt: absent

Oromediterranean belt: absent

Montane belt: absent

Submediterranean belt: absent

Padanian area: absent

Humid submediterranean belt: absent

Humid mediterranean belt: very rare

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

Index Fungorum GBIF

P.L. Nimis CC BY-SA 4.0

GZU Ref.Herb. Poelt (2-93)

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

Herbarium: GZU Ref.Herb. Poelt (2-93)
2003/04/28