Cortaderia sericantha (Steud.) Hitchc., Contr. U.S. Natl. Herb. 24: 348. 1927.

Testoni, Daniel & Linder, H. Peter, 2017, Synoptic taxonomy of Cortaderia Stapf (Danthonioideae, Poaceae), PhytoKeys 76, pp. 39-69 : 57

10. Cortaderia sericantha (Steud.) Hitchc., Contr. U.S. Natl. Herb. 24: 348. 1927. Figs 1I , 3F

Danthonia sericantha Steud., Syn. Pl. Glumac. 1(3): 246. 1854. Type: Ecuador, Quito "On boggy plains on the eastern Cordillera at 13000 feet above sea level", sine data, W. Jameson 93 (lectotype designated by Connor & Edgar, Taxon 23: 602 (1974): K!; isolectotypes: K! - frag US!, OXF!, TCD!).

Danthonia jubata Sodiro, Revista Colegio Nac. Vicente Rocafuerte 12: 91. 1930. Type: Ecuador, Pinchincha, sine data, A. S. J. Mille s.n. (NY, MO photo!, US!).

Etymology.

serios (Greek) = silken + Anthos (Greek) = flower. Presumably this refers to the silky-haired leaves, a diagnostic trait for this species.

Taxonomy.

This species is very distinctive in Cortaderia by its very villous leaves, which are rolled rather than flat, and quite pungent; the compact inflorescences with short inflorescence branches; the glumes with three veins and which are much longer than the packet of florets; and the tuft of hair at the base of the spikelets. The inflorescences are similar to those of Cortaderia egmontiana , but the villous leaves immediate distinguish our species from Cortaderia egmontiana . The intact leaf sheaths, pungent leaf tips, and compact growth form related this species to Cortaderia pungens and Cortaderia echinata . The remarkably large glumes, much overtopping the packet of florets, are shared with Cortaderia echinata .

The leaf anatomy (Fig. 3F ) could be unique in the genus. The abaxial half of the leaf, in cross-section, consists of colourless collenchyma. The vascular bundles are very slender, and the girders taper towards the adaxial epidermis. Adaxially the leaves are only very slightly grooved.

Figures

Figure 1. Lemmas of selected species of Cortaderia. A Cortaderia selloana, Juergens 40 (B) B Cortaderia araucana, Borchers s. n. (US) C Cortaderia speciosa, P. M. Peterson 12766 (US) D Cortaderia vaginata, L. B. Smith, P. R. Reitz & R. Klein 7761 (B) E Cortaderia egmontiana, P. M. Peterson, R. J. Soreng & N. Refulio-Rodriguez 17508 (US) F Cortaderia modesta, A. Chase 8288 (US) G Cortaderia hieronymi, A. Burkart et al. 30395 (P) - note that awn and setae are much longer than illustrated H Cortaderia nitida, S. Laegaard 52786 (K) I Cortaderia sericantha, E. Asplund 17175 (B) J Cortaderia bifida, D. N. Smith & J. Cabanillas 7167 (US) K Cortaderia hapalotricha, J. C. Solomon & R. Chevalier 16620 L Cortaderia columbiana, J. P. Schulz 318 (US). All at same magnification.

Figure 3. Leaf anatomy of Cortaderia, as evident from transverse sections. A Cortaderia egmontiana (Moore 2677) B Cortaderia modesta (Glaziou 17913) C Cortaderia hieronymi (Garcia 563) D Cortaderia nitida (Laegaard 53121) E Cortaderia boliviensis (Beck 11273); F Cortaderia sericantha (Ramsay 967); G Cortaderia echinata (Peterson 21587) H Cortaderia bifida (Renvoize 4202) I Cortaderia hapalotricha (Laegaard 53305) J Cortaderia roraimensis (Maguire 60448). Structures referred to in the descriptions are labelled as follows: 1, multi-layered abaxial sub-epidermal collenchyma layer; 2, adaxial islands of collenchyma in the abaxial grooves; 3, chlorenchyma; 4, primary vascular bundle; 5, midrib.