The grass genera of the world
Type species: P. kainii.
Habit, vegetative morphology. Perennial; caespitose. Culms 1500–2000 cm high; woody and persistent (without nodal roots); to 3 cm in diameter; cylindrical; leaning; branched above (from the upper culm). Buds from which the primary culm branches arise 1. Primary branches thinner than the stem, 3–10; clumped (with one dominant). The branching dendroid. Culm leaf sheaths present; deciduous; leaving a persisten girdle; conspicuously auriculate. Culm leaves with conspicuous blades. Culm leaf blades narrower than the sheath, erect, triangular. Culm internodes hollow. Rhizomes pachymorph. Leaf blades glabrous, lanceolate (acuminate); broad; 26–31 cm long, 39–60 mm wide; pseudopetiolate; disarticulating from the sheaths.
Reproductive organization. Plants bisexual, all with bisexual spikelets; with hermaphrodite florets. The spikelets hermaphrodite.
Inflorescence. Inflorescence indeterminate; with pseudospikelets (the spikelets with basal axillary buds); of spicate main branches (comprising bractiferous synflorescences clustered at the nodes, leafless between the clusters); spatheate (the clusters with spathaceous subtending bracts, the lateral spikelets prophyllate); a complex of partial inflorescences and intervening foliar organs.
Female-fertile spikelets. Spikelets 25–52 mm long; lanceolate; compressed laterally; disarticulating above the glumes; disarticulating between the florets; with distinctly elongated rachilla internodes between the florets (the internodes 1–3 mm long). Rachilla prolonged beyond the uppermost female-fertile floret; hairless; the rachilla extension with incomplete florets.
Glumes two; shorter than the spikelets; pointed; awnless; ovate, apically acute, persistent, similar. Spikelets with incomplete florets. The incomplete florets distal to the female-fertile florets. The distal incomplete florets merely underdeveloped; awnless. Spikelets without proximal incomplete florets.
Female-fertile florets 5–12. Lemmas similar in texture to the glumes; entire; pointed; 9–13 mm long, ovate-acuminate, awnless; hairless (?); non-carinate. Palea present; relatively long (10–13.5 mm long); entire (the apex acute). Lodicules absent. Stamens 6. Stigmas 3.
Fruit, embryo and seedling. Fruit not grooved. Pericarp fused.
Classification. Watson & Dallwitz (1994): not described separately. Soreng et al. (2015): Bambusoideae; Bambusodae; Bambuseae; Bambusinae. 1 species (P. kainii).
Distribution, phytogeography, ecology. Papuasia.
References, etc. Morphological/taxonomic: Clayton et al. (2016), GrassBase; Kellogg.
Special comments. 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: 13th November 2017. delta-intkey.com/grass’.