Cortaderia hapalotricha (Pilg.) Conert, Syst. Anat. Arundineae 102. 1961.

Testoni, Daniel & Linder, H. Peter, 2017, Synoptic taxonomy of Cortaderia Stapf (Danthonioideae, Poaceae), PhytoKeys 76, pp. 39-69 : 61-63

15. Cortaderia hapalotricha (Pilg.) Conert, Syst. Anat. Arundineae 102. 1961. Figs 1K , 3I

Danthonia hapalotricha Pilg., Bot. Jahrb. Syst. 25: 715. 1898. Type: Colombia, Páramo between Usme and Pasca, Cudinamarca, June 1868, M. A. Stübel 111C (lectotype, designated as holotype by Connor & Edgar, Taxon 23: 598 (1974): B, frag. US!).

Cortaderia scabriflora Swallen, Contr. U.S. Natl. Herb. 29: 252. 1948. Type: Ecuador, near Toreador, between Molleturo and Quinoas, Province of Azuay, along lake shore, 15 June 1943, J. A. Steyermark 53188 (lectotype, designated as holotype by Connor & Edgar, Taxon 23: 602 (1974): US 00027057!; isolectotype: NY!).

Etymology.

hapalos (Greek) = soft + thrix (Greek) = hair. It presumably refers to the densely pubescent rhachilla.

Nomenclatural comments.

The type specimen of Cortaderia scabriflora is intermediate between Cortaderia hapalotricha , Cortaderia pungens and Cortaderia planifolia . It has the lemma structure of Cortaderia pungens , the folded leaves typical of Cortaderia planifolia , the pungent leaves typical of both, but the size of Cortaderia hapalotricha . Overall, it approaches Cortaderia hapalotricha .

Taxonomy.

Connor and Edgar (1974) note "The golden brown panicles with very hairy branches are obvious characteristics of this species.", but these characters are variable in the species. Cortaderia hapalotricha is morphologically very close to Cortaderia columbiana , especially by the inner leaf surfaces directly above the ligule being densely and finely woolly. Genetically, the two species are strongly supported as sister species. Cortaderia hapalotricha can be separated from Cortaderia columbiana by the longer glumes, which are much longer than the spikelets, by the denser inflorescences, and by the lemmas which have well developed setae. It is also similar to Cortaderia bifida , but the lemmas are longer and the setae shorter. Most convincing might be anatomical differences, these need to be corroborated with more sections. The leaf anatomy and spikelet structure indicate a very close relationship with Cortaderia pungens , and the two might just be ecological variants of each other. However, the growth form is quite different, and we keep them separate on this basis.

Leaf anatomically (Fig. 3I ) this species is very similar to Cortaderia columbiana , with well developed adaxial ribs, and girders linking the vascular bundles to both surfaces, as well as well developed adaxial epidermal papillae. The only difference may be the absent or poorly developed abaxial subepidermal sclerenchyma layer.

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.