Steyermarkochloa angustifolia

HABIT Perennial; caespitose. Culms erect; 40–350 cm long. Leaves cauline; 1 per branch. Leaf-sheaths solid and functionally replacing culm; longer than adjacent culm internode. Ligule absent. Leaf-blades 40–150 cm long; 2.8–6.5 mm wide. Leaf-blade apex hooded.

INFLORESCENCE Monoecious; with male and female spikelets in the same inflorescence. Synflorescence on a separate leafless culm. Inflorescence a panicle.

Panicle spiciform; linear; 7–49 cm long. Primary panicle branches accrescent to a central axis; with lateral stumps on axis. Panicle axis with rounded ribs.

Sexes segregated; with male below. Spikelets solitary. Fertile spikelets pedicelled. Male spikelets pedicelled. Pedicels oblong; angular; 0.4–1 mm long (male 4–13mm).

FERTILE SPIKELETS Spikelets comprising 1 basal sterile florets; 1 fertile florets; with diminished florets at the apex. Spikelets lanceolate; curved; dorsally compressed; 9–17 mm long; falling entire.

GLUMES Glumes dissimilar; shorter than spikelet. Lower glume lanceolate; 2.2–4.7 mm long; 1–1.3 length of upper glume; herbaceous; 2-keeled; 3–7 -veined. Lower glume primary vein scaberulous. Lower glume surface flat. Lower glume apex truncate, or obtuse. Upper glume lanceolate; 2.1–3.7 mm long; 0.33 length of adjacent fertile lemma; herbaceous; without keels; 3–6 -veined. Upper glume apex truncate, or obtuse.

FLORETS Basal sterile florets barren; without significant palea. Lemma of lower sterile floret lanceolate; 4.8–7 mm long; 0.5 length of spikelet; herbaceous; 5–9 -veined; ribbed; obtuse. Fertile florets female. Fertile lemma lanceolate; 6.1–9 mm long; herbaceous; without keel; (5–)9–11(–13) -veined. Lemma lateral veins ribbed. Lemma apex truncate, or obtuse. Palea lanceolate; tightly convolute around flower; falcate; 1.3–1.5 length of lemma; spongy; (5–)7–11 -veined. Palea keels approximate (sulcate above). Apical sterile florets distinct from fertile; 1 in number; barren; linear; 0.3–3 mm long.

FLOWER Lodicules absent. Anthers 2; 2.2–3.8 mm long. Filaments free, or united in a tube. Stigmas 2; terminally exserted.

FRUIT Caryopsis with adherent pericarp; fusiform; 5 mm long. Embryo 0.2 length of caryopsis. Hilum linear; 0.7 length of caryopsis.

MALE Male spikelets similar to female but less developed; 2 flowered; without rhachilla extension, or with rudimentary apical florets; lanceolate; 4.5–7.5 mm long. Male spikelet glumes 2. Male spikelet lemma 3–7 -veined.

DISTRIBUTION South America: northern South America and western South America.

NOTES Steyermarkochloeae. WDC.

Please cite this publication as detailed in How to Cite Version: 3rd February 2016.