Schistidium helveticum (Schkuhr) Deguchi

Guerra, Juan, Cano, María J., Martínez, Mónica, Jiménez, Juan A. & Gallego, M. Teresa, 2021, Schistidium apocarpum complex (Grimmiaceae, Bryophyta) in the Baetic Mountain Ranges, southern Iberian Peninsula, Cryptogamie, Bryologie 20 (5), pp. 45-71 : 54-58

4. Schistidium helveticum (Schkuhr) Deguchi

( Fig. 9)

Revue bryologique et lichénologique n.s. 45: 434 (1979). — Grimmia helvetica Schkuhr , Deutschland’s kryptogamische Gewächse 2 (2): 48 (1811).

Schistidium singarense (Schiffn.) Laz. , Journal Institute of Botany Academy of Science of Ukraine 26-27: 205 (1938).

HABITAT. — Exposed calcareous rocks, rarely on tree bases ( Ulmus ) or schists, from 680 to 2120 m. Distribution: Figure 10. Very common species in the Iberian Peninsula on limestone substrates.

Plants

Large to medium-sized or small, 1-3.5 cm long, forming dense tufts, jet-black to olivaceous or brownish.

Leaves

More or less straight, erect, imbricate, lanceolate to ovate-lanceolate, acute to subacute, (1.5)1.7-2.5 × 0.4-0.6 mm.

Hair-point

Present, rarely absent, short, finely to coarsely spinulose, (0) 0.1-0.2 mm long.

Lamina

Smooth, in upper and central part irregularly 2-stratose to 1-stratose; margins recurved along almost all its length except at the base, frequently 3- to 4-stratose in upper and central part.

Laminal cells

In upper and central part isodiametric to oblong or oblate towards the margins, slightly to strongly sinuose, 12-18(20) µm long, basal cells thick-walled, sinuose, 25-48 × 6-12 µm.

Perichaetial leaves

Ovate-lanceolate to lanceolate, 2-4 × 0.7-1.1 mm.

A B C D E F G H N I M J K L

Urn

Oblong-cylindrical, 1-1.5 × 0.5-0.8 mm, yellowish to orange-brown.

Exothecial cells

Variable in shape and size, predominantly oblong, stomata absent.

Peristome teeth

300-450 µm long, perforated or cribrose, with perforations arranged in parallel lines, orange-red.