Cenchrus elegans (Hassk.) Veldk., 2014

Veldkamp, J. F., 2014, A revision of Cenchrus incl. Pennisetum (Gramineae) in Malesia with some general nomenclatural notes, Blumea 59 (1), pp. 59-75 : 68

8. Cenchrus elegans (Hassk.) Veldk. , comb. nov.

Sericura elegans Hassk. , Flora 25, 2, Beibl. 1 (1842) 2; (1843) 116; (1844) 17; non Pennisetum elegans Nees ex Steud.(1854) . — Gymnothrix elegans Buse (Feb.1854) preprint:28;(Aug. 1854) 368. — Type:not indicated, not found in BO, L. — Neotype: Zollinger 2367 (Steud. (June 1854: 58, 60)) was partly taken from the plants in the Hortus Bogoriensis that provided the type of Hasskarl’s species, designated here.

Gymnotrix macrostachys Brongn.(1831) 104,t. 11,f.1–9. — Pennisetum macrostachys Trin. (1834) 177 ( ‘ macrostachyum ’), non Cenchrus macrostachys Hochst. ex Steud. (1854) . — Type: Dumont d’Urville s.n. (holo P).

[ Saccharum caninum Reinw. ex Blume (1823) 38, nomen]. — Pennisetum caninum Koord. (1911) 140, nom. superfl. — Cenchrus caninus [Reinw. ex Blume] Morrone in Chemisquy et al. (2010) 127, nom. inval. — Type: Reinwardt s.n. (holo L, sh. 908.93-710).

Perennials. Culms erect to geniculate at base, not rooting in the decumbent nodes, not stoloniferous, rhizomatous, 1–3 m long, solid, nodes glabrous. Ligule a ciliolate rim, c. 0.15 mm long. Blades flat, 10–65 cm by (6–) 8–35 mm, margins scaberulous. Peduncle puberulous below the panicle. Panicle exserted, many-spikeled, 15–40 cm long, common axis puberulous. Involucre stipitate, disarticulating at base. Bristles many, rather stiff, scaberulous, unequal, longest ones 32–55 mm long. Spikelets 1 within the involucre, pedicelled, 4.5–6.5 mm long. Lower glume 1.25–1.75 mm long, 0.39–0.53 times as long as the upper glume; upper glume 2.5–3.4 mm long, 1-nerved. First lemma epaleate, acuminate, membranous, 3–5-nerved, glabrous, nerves smooth; second lemma membranous.Anthers 1.65–2.1 mm long, apex glabrous. 2n =?

Distribution — Widespread in W Malesia into the Pacific (Solomon Isl.), but not in the Malay Peninsula (once cultivated in Penang and Singapore) nor in Australia.

Habitat — Sunny, infertile soil, slopes, along hollow roads, Imperata fields, gravel beds, savannahs, 0–2130 m altitude.

Uses — Cultivated as an ornamental, best below 100 m altitude. In the Eastern Highlands of Papua New Guinea a form with uniformly reddish purple stems, leaves, and panicles occurs between 1500–2100 m altitude. This might be the same as what is known as the cv. Burgundy Giant of horticulturists. See P. advena .

Young stems eaten in the Baliem Valley, but otherwise too hard for fodder.

Vernacular name — Pacific fountaingrass.

Notes — Blume’s combination had no description and is invalid. He referred to Reinwardt (‘R’). Koorders made the combination Pennisetum caninum but included the older P. macrostachys and Sericura elegans , and it is therefore superfluous. Morrone mentioned the specimens cited by Koorders as syntypes: Reinwardt s.n., Junghuhn s.n., and Zollinger s.n. (‘types not located’). They are of course in L; the latter two cannot be Blume types, as they were collected many years after 1823. He thus excluded the type of G. macrostachys and actually described a new species, which is invalidly published. For some reason Soreng & Pennington (2003: 532) have equated this species with the older Pennisetum peruvianum Trin. (1836) ≡ Cenchrus peruvianus (Trin.) Morrone.According to Clayton et al. (2014) they differ:

–. Ligule a ciliolate rim. Inflorescence terminal and axillary. Involucre base obtuse. Spikelets 4.5–6.5 mm long. Lower glume oblong, hyaline; upper glume oblong. First lemma el- liptic, chartaceous, acuminate; second lemma 4.5–6.5 mm long, chartaceous, acuminate. — Old World... C. elegans

–. Ligule a fringe of hairs. Inflorescence terminal. Involucre base truncate. Spikelets 3.7–4.3 mm long. Lower glume ovate, membranous; upper glume ovate. First lemma oblong, membranous, acute; second lemma 3.7–4.2 mm long, co- riaceous, acute. — S America........... C. peruvianus