Dimeria

Veldkamp, J. F., 2016, A revision of Dimeria (Gramineae-Dimeriinae) in Malesia with a note on Cymbachne, Blumea 61 (3), pp. 207-214 : 208

Dimeria — Map 1

Dimeria R.Br. (1810) 204; Bor (1953) 553; Teerawat. et al. (2014) 137. — Type: Dimeria acinaciformis R.Br.

Haplachne J. Presl (1830) 234. — Dimeria R.Br. [sect.] Haplachne (J.Presl) Endl. (1836) 106. — Type: Haplachne pilosissima J.Presl [= Dimeria chloridiformis (Gaudich.) K.Schum. & Lauterb. ].

Didactylon Zoll.& Moritzi in Moritzi (1846) 99. — Lectotype: Didactylon simplex Zoll. & Moritzi (= Dimeria ornithopoda Trin. ), designated by Clayton & Renvoize (1986: 349).

Annual or perennial, caespitose. Culms internodes hollow. Leaf blades linear. Ligules truncate, margin lacerate or fimbriate. Inflorescences determinate, espatheate, composed of 1–14 digitate racemes. Spikelets numerous, hermaphrodite, solitary, lateral to and partially embedded in the rachis, secund, biseriate, pedicellate, laterally compressed. Glumes more or less equal, awnless, carinate, 1–3-nerved. Lower floret epaleate, sterile, lemma awnless, 0-nerved, similar in texture to the upper one; upper lemma incised, awnless to awned from the sinus, glabrous, 1–3-nerved. Lodicules absent or very small. Stamens 2, rarely 3 (see note). Styles fused, stigmas 2. Hilum punctiform, embryo large. x = 7, 25.

Distribution — C. 67 species from Madagascar to S Korea, Micronesia and northern Australia. In Malesia 4 species.

Note — Brown (1810) described the type species D. acinaciformis with three stamens, other authors (e.g. Hackel 1889: 86 ‘certissime’) have reported two. Presl (1830) said two, his artist depicted three. Kiran Raj erroneously (fide litt.) reported the presence of 3 stamens in D. thwaitesii Hack.