Froesiochloa G.A. Black
Named for R.L. Fróes, botanical explorer of the Amazon region.
Habit, vegetative morphology. Perennial. The flowering culms leafy. Culms herbaceous. Leaves not basally aggregated; without auricular setae. Leaf blades lanceolate to ovate (?); pseudopetiolate; rolled in bud; an unfringed membrane.
Reproductive organization. Plants monoecious with all the fertile spikelets unisexual; without hermaphrodite florets. The spikelets of sexually distinct forms on the same plant; female-only and male-only. The male and female-fertile spikelets mixed in the inflorescence (a central female surrounded by 6–10 males, in each cluster). The spikelets overtly heteromorphic (the female spikelets lanceolate).
Inflorescence. Inflorescence without pseudospikelets; a false spike, with spikelets on contracted axes (of 2–4 deciduous clusters on a central axis). Spikelet-bearing axes disarticulating; falling entire (the clusters falling).
Female-sterile spikelets. Male spikelets 1 flowered, lemma membranous and 3 nerved, lodicules 3, 6 stamens with joined filaments. Rachilla of male spikelets terminated by a male floret. The male spikelets without glumes; without proximal incomplete florets; 1 floreted. The lemmas awnless. Male florets 1; 6 staminate. The staminal filaments joined.
Female-fertile spikelets. Spikelets lanceolate; compressed dorsiventrally; falling with the glumes (i.e. with the clusters). Rachilla terminated by a female-fertile floret.
Glumes two; about equalling the spikelets to exceeding the spikelets; long relative to the adjacent lemmas; pointed (acuminate, herbaceous); awnless; non-carinate; similar. Lower glume 3–7 nerved. Upper glume 3–7 nerved. Spikelets with female-fertile florets only; without proximal incomplete florets.
Female-fertile florets 1. Lemmas decidedly firmer than the glumes (leathery); entire; pointed (‘subacute’); mucronate; non-carinate; 5–7 nerved. Palea present; awnless, without apical setae; 2-nerved, or several nerved (?). Lodicules present; 3. Stamens 0. Ovary glabrous.
Fruit, embryo and seedling. Disseminule consisting of the disarticulated spikelet-bearing inflorescence unit.
Taxonomy. Bambusoideae; Oryzodae; Olyreae.
Distribution, ecology, phytogeography. 2 species; Brazil, Guiana. Mesophytic; shade species. In forests.
Neotropical. Caribbean, Venezuela and Surinam, Amazon, and Central Brazilian.
References, etc. Morphological/taxonomic: G.A. Black (1950: not yet seen - data here from Clayton and Renvoize 1986).
Special comments. Fruit data wanting. Anatomical data wanting.
Cite this publication as: Watson, L., and Dallwitz, M. J. (1992 onwards). ‘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.’ http://biodiversity.uno.edu/delta/. Version: 18th August 1999. Dallwitz (1980), Dallwitz, Paine and Zurcher (1993 onwards, 1998), and Watson and Dallwitz (1994), and Watson, Dallwitz, and Johnston (1986) should also be cited (see References).