Chasechloa A. Camus
Sometimes referred to Echinolaena
Habit, vegetative morphology. Culms herbaceous; branched above. Culm nodes glabrous. Leaves not basally aggregated; non-auriculate. Leaf blades broad; slightly cordate; without cross venation; persistent.
Reproductive organization. Plants bisexual, with bisexual spikelets; with hermaphrodite florets. The spikelets all alike in sexuality.
Inflorescence. Inflorescence of spicate main branches (pectinate racemes); espatheate; not comprising ‘partial inflorescences’ and foliar organs. Spikelet-bearing axes persistent. Spikelets solitary; secund.
Female-fertile spikelets. Spikelets 5 mm long; compressed laterally; falling with the glumes. Rachilla terminated by a female-fertile floret. Hairy callus absent.
Glumes two; relatively large; more or less equal; shorter than the adjacent lemmas; lateral to the rachis; hairy (with stiff, tubercle-based hairs over the lower part of the keel); pointed; awnless (apiculate); carinate; with the keel conspicuously winged (over its top third); similar. Lower glume 4–5 nerved. Upper glume 3–6 nerved. Spikelets with incomplete florets. The incomplete florets proximal to the female-fertile florets. Spikelets with proximal incomplete florets. The proximal incomplete florets 1; paleate; male. The proximal lemmas awnless; 11 nerved; decidedly exceeding the female-fertile lemmas; less firm than the female-fertile lemmas; not becoming indurated.
Female-fertile florets 1. Lemmas decidedly firmer than the glumes; not becoming indurated; entire; pointed; awnless; hairless; carinate; having the margins inrolled against the palea; 5 nerved. Palea present; relatively long; 2-nerved; 2-keeled. Lodicules present; 2; free; fleshy; glabrous; not or scarcely vascularized. Stamens 3. Anthers not penicillate; without an apically prolonged connective. Ovary glabrous. Styles fused. Stigmas 2; white (seemingly, from dried material).
Abaxial leaf blade epidermis. Costal/intercostal zonation conspicuous. Papillae absent. Intercostal zones exhibiting many atypical long-cells. Mid-intercostal long-cells rectangular; having markedly sinuous walls. Microhairs present; panicoid-type; 51–54 microns long; 30–31.5 microns wide at the septum. Microhair total length/width at septum 6–6.1. Microhair apical cells 8.4–9 microns long. Microhair apical cell/total length ratio 0.58–0.59. Stomata common; 40–45 microns long. Subsidiaries triangular. Guard-cells overlapping to flush with the interstomatals. Intercostal short-cells absent or very rare. Costal short-cells conspicuously in long rows. Costal silica bodies ‘panicoid-type’; dumb-bell shaped (the cross-bars seemingly missing in the material seen, thus simulating saddles and crescents).
Transverse section of leaf blade, physiology. C3; XyMS+. Midrib conspicuous; with one bundle only. All the vascular bundles accompanied by sclerenchyma. Combined sclerenchyma girders present. Sclerenchyma all associated with vascular bundles.
Taxonomy. Panicoideae; Panicodae; Paniceae.
Distribution, ecology, phytogeography. 3 species; Madagascar.
Paleotropical. Madagascan.
References, etc. Leaf anatomical: this project.
Special comments. Fruit 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).