Piptatherum coerulescens P. Beauv., 1812

Vázquez, Francisco Maria, Márquez, Francisco, García, David & Oualidi, Jalal El, 2025, A taxonomic revision of Stipeae s. l. tribe (Poaceae) in N Africa, Phytotaxa 699 (1), pp. 1-174 : 99

Piptatherum coerulescens P. Beauv. ( Figure 55 ).

Lemma dorsal surface: Characterised by rectangular long cells of (20–)30–90(–110) × (5–)6–8(–10) µm, undulated walls up to 1 µm thick, linear distribution. Short cells: main Silica cells 10–22(–25) × 10–16(–19) µm, circular to elongate, frequent, in pairs with cork cells, situated between long cells, frequently solitary, density 20–28(–31) silica cells/100 µm 2; Cork cells 2–4 × 7–10 µm, fusiform to reniform, sporadic, always with a silica cell. Spines and hairs: Hooks, Prickles, and Macro-hairs not studied.

Lemma apical surface: Characterised by long cells similar to those of the dorsal area, no significant differences. Short cells: Silica cells of equal size, morphology and distribution, denser in dorsal area 25–35(–38) silica cells/100 µm 2; Cork cells of equal size, morphology and distribution to those in dorsal area. Spines and hairs: Hooks, Prickles, and Macro-hairs not studied.

Awn base surface: Long cells (22–)28–42(–48) × (6–)8–10(–11) µm, extremes rounded to acute, smooth walls up to 1 µm thick, linear distribution. Short cells absent. Spines and hairs: Prickles of two types: Short Prickles of ovoid to circular base 18–24(–26) × 14–19(–21) µm and up to 55 µm long; Long Prickles of ovoid base 26–45(–57) × 18–28(–32) µm and up to 92 µm long, distributed helicoidally. Stomata paracytic (Parallel wall cells type) situated between the prickles in lines 11–20 µm long, density (4–) 9–14(–16) stomata/100 µm 2.

Material studied: Morocco: Ben Taieb, 520 m. a.s.l., 5-V-2022, M . Chamboleyron , ECWP n.n.; Missour , Jbel Missour, 1400 m.a.s.l., 6-XII-2015, M . Chamboleyron , ECWP n.n.

Figures

FIGURE 55. Lemma surface Piptatherum coerulescens A. Lemma central dorsal surface view. B. Lemma apex dorsal surface view. C. Lemma apex and awn. D. Awn surface. lc. Long cell. sc. Silica cell. cc. Cork cell. p. Prickle. s. Stomata. Bars indicate 100 µm.