Dimeria gracilis Nees ex Steud.

Veldkamp, J. F., 2016, A revision of Dimeria (Gramineae-Dimeriinae) in Malesia with a note on Cymbachne, Blumea 61 (3), pp. 207-214 : 209

2. Dimeria gracilis Nees ex Steud.

Dimeria gracilis Nees ex Steud. (1854) 413. — [ Dimeria avenacea (Retz.) C.E.C.Fisch. subvar. gracilis (Nees ex Steud.) Roberty (1960) 398, 402, nom. inval.]. — Type: Macrae 229 in Herb. Lindley (holo P; CGE).

Dimeria laxiuscula Thwaites ex Trimen (1885) 272. — Type: CP 3863 (Thwaites) (holo PDA; BO, K, P).

Dimeria leptorhachis Hack.(1889) 90 (incl. subsp. genuina Hack. ,nom.inval.). — [ Dimeria avenacea (Retz.) C.E.C.Fisch. subvar. leptorhachis (Hack.) Roberty (1960) 398,nom. inval.]. — Lectotype: CP 24 (Thwaites) (W 1889­ 0058700; iso G, K, PDA), designated by Roberty (1960: 398).

Dimeria leptorhachis Hack. subsp. velutina Hack. (1889) 90. — Dimeria velutina (Hack.) Bor (1952 ‘1951’) 458. — [ Dimeria avenacea (Retz.) C.E.C. Fisch. subvar. velutina (Hack.) Roberty (1960) 399, 402, nom. inval.]. — Lectotype: Griffith 6799 (K 000245776; iso G, W 1916­0034768), designated by Teerawatananon et al. (2014: 145).

Perennials. Culms 0.45–1.4 m long. Nodes glabrous, puberulous, or bearded. Ligules 0.3–2 mm long, margin ciliolate (30 x!). Leaf blades 15–25 cm by 2–12 mm, glabrous or pilose. Racemes 3–11, rachis filiform, terete, 4–20 cm long, 0.2–0.5 mm wide, internodes 2–4 mm long, margin glabrous (30 x!), smooth (30 x!). Pedicels 0.5–2.5 mm long. Spikelets 4.5–8 mm long. Callus hairs 0.5–1 mm long. Lower glumes keel scaberulous (30 x!) or pilose (30 x!), apex obtuse to mucronate, mucro 0–0.8 mm long, winged or not; upper glumes acuminate to mucronate, mucro 0–0.5 mm long, keel winged or not, pilose (30 x!), narrow, not rugose. Awns 5–14 mm long, incl. 2.5–4 mm long column. Anthers 2–3.5 mm long.

Distribution — Sri Lanka, W India (Goa, Karnataka, Maha- rasthra), Burma (Tenasserim), Thailand (Trat), Cambodia (Kam- pong Speu), Vietnam (Dalat), Malesia: Malay Pen. (Kedah).

Habitat — On scrub, grass land, pine and dipterocarp forest, 600–975 m altitude.

Notes — The differences between D. leptorhachis and its var. velutina is only in the pubescence of the sheaths and leaves, which is insufficient to recognise these forms at any level. The differences with D. gracilis were equally unimportant.

Collected in the same site in Kedah, G. Jerai, were Burkill 3304 (L, SING) and KLU 8157 (Kassim & Carrick) (KLU).

Distribution remarkable, everywhere apparently very local.