Plagiothecium denticulatum (Hedw.) Schimp.

Wolski, Grzegorz J., Khan, Aamir Shehzad & Paszko, Beata, 2023, New taxa of Plagiothecium (Plagiotheciaceae) from Pakistan, PhytoKeys 236, pp. 1-16 : 1

Plagiothecium denticulatum (Hedw.) Schimp.

Plagiothecium denticulatum (Hedw.) Schimp., Bryologia Europaea 5: 190, 501, Tab. VIII (1851).

≡ Hypnum denticulatum Hedw., Species Muscorum Frondosorum 237 (1801). Lectotype (fide Ireland 1969): "St. Cr. 4. p. t. 30", leg. Starke, Germany?, G (n.v.).

Description.

Plants green to yellowish green, with metallic luster; stem in cross section rounded, 200-250 μm in diameter; leaves not folded, julaceous, elliptical-ovate, asymmetrical; leaves 2.2-3.0 × 1.0-1.3 (M 2.6 × 1.1) mm, shortly tapering to acute, denticulate apex; costae two, extending usually to ½ of the leaf length, ranging 440-810 (M 625) μm; cell areolation loose; length and width of cells very variable, but dependent on location: 85-140 × 15-28 (M 113 × 22) μm at the apex; 120-210 × 15-30 (M 165 × 23) μm at midleaf; 116-205 × 18-37 (M 160 × 28) μm toward insertion; broad decurrency 400-700 (M 555) μm; alar cells rounded, clearly inflated, 45-90 × 20-50 (M 68 × 35) μm; sporophytes not found in this material (Fig. 1 ). In these studies, Plagiothecium denticulatum has been recorded on soil and boulders.

Figures

Figure 1. The most important taxonomic features of Plagiothecium denticulatum A shape of apex B, C dimension of cells (B from the middle C basal part of the leaf) D decurrent cells E leaf shape (from M. Higuchi 20462).