The grass genera of the world

L. Watson, T.D. Macfarlane, and M.J. Dallwitz

Perrierbambus A. Camus

Habit, vegetative morphology. Bushy perennial. Culms woody and persistent; not scandent; branched above. Primary branches 11–20. The branching dendroid. Culm leaf sheaths present. Rhizomes leptomorph. Leaves not basally aggregated; with auricular setae. Leaf blades not cordate, not sagittate; pseudopetiolate; disarticulating from the sheaths. Contra-ligule absent.

Reproductive organization. Plants bisexual, all with bisexual spikelets; with hermaphrodite florets.

Inflorescence. Inflorescence determinate; reduced to a single spikelet to few spikeleted, or many spikeleted (depending how the ‘inflorescence’ is delimited); with spikelets solitary or 2–3, terminating simple branches which are borne in fairly distant, dense semi-whorls; the slender individual branches each bearing many small-bladed leaves, the latter clustered towards the tip and almost involucrate around the spikelet(s); espatheate (the inflorescence surrounded by involucral leaf blades, instead of spathiform sheaths); not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes not racemose; persistent. Spikelets not secund; shortly pedicellate.

Female-fertile spikelets. Spikelets unconventional (or at least, hard to interpret in the inadequate material seen); elliptic, or lanceolate; compressed laterally to not noticeably compressed. Rachilla prolonged beyond the uppermost female-fertile floret (in all the few spikelets dissected); hairless; the rachilla extension with incomplete florets. Hairy callus absent.

Glumes two; very unequal; hairless; glabrous; pointed; awnless (apiculate); non-carinate (dorsally rounded); similar (lanceolate-ovate). Lower glume 9–11 nerved. Upper glume 13 nerved. Spikelets with incomplete florets (in the material seen). The incomplete florets distal to the female-fertile florets. The distal incomplete florets 1; merely underdeveloped; awnless. Spikelets without proximal incomplete florets.

Female-fertile florets 1. Lemmas lanceolate-ovate; similar in texture to the glumes to decidedly firmer than the glumes (firmly membranous); not becoming indurated; entire; awnless; hairless; glabrous; without a germination flap; about 13–15 nerved. Palea present; relatively long; not convolute; entire; awnless, without apical setae; textured like the lemma; not indurated; several nerved; 2-keeled (but the keels closely apposed). Palea keels wingless. Lodicules present; 3; free; membranous; glabrous; heavily vascularized. Stamens 5, or 6 (one seemingly separate from the whorl of five, in some of the spikelets seen). Anthers not penicillate; without an apically prolonged connective. Ovary inconspicuously apically hairy (at the tip); seemingly without a conspicuous apical appendage (but the apex hardening to form a shiny beak on the fruit). Styles fused. Stigmas 3.

Fruit, embryo and seedling. Pericarp fleshy; free.

Classification. Watson & Dallwitz (1994): Bambusoideae; Bambusodae; Bambuseae. Soreng et al. (2015): Bambusoideae; Bambusodae; Bambuseae; Hickeliinae. 2 species.

Distribution, phytogeography, ecology. Madagascar.

Special comments. The spikelet morphology is evidently ‘difficult’, and this description reflects very tentative interpretation of depauperate and inadequate (type) material. Fruit data wanting. Anatomical data wanting.

We advise against extracting comparative information from the descriptions. This is much more easily achieved using the DELTA data files or the interactive key, which allows access to the character list, illustrations, full and partial descriptions, diagnostic descriptions, differences and similarities between taxa, lists of taxa exhibiting or lacking specified attributes, distributions of character states within any set of taxa, geographical distribution, and classifications. See also Guidelines for using data taken from Web publications.

Cite this publication as: ‘Watson, L., Macfarlane, T.D., and Dallwitz, M.J. 1992 onwards. The grass genera of the world: descriptions, illustrations, identification, and information retrieval; including synonyms, morphology, anatomy, physiology, phytochemistry, cytology, classification, pathogens, world and local distribution, and references. Version: 11th December 2017.’.