Tuctoria greenei

HABIT Annual; caespitose. Culms erect, or decumbent; 5–15(–30) cm long. Leaves without demarcation between sheath and blade. Leaf-sheaths viscid. Ligule absent. Leaf-blades 2–12 cm long; 2–5 mm wide; viscid; aromatic. Leaf-blade surface pilose; sparsely hairy.

INFLORESCENCE Inflorescence composed of racemes; exserted.

Racemes 1; single; multilateral; 4–8 cm long. Rhachis angular. Spikelet packing broadside to rhachis; distant (below).

Spikelets solitary. Fertile spikelets sessile.

FERTILE SPIKELETS Spikelets comprising 10–40 fertile florets; with diminished florets at the apex. Spikelets oblong; laterally compressed; 12–23 mm long; breaking up at maturity; disarticulating below each fertile floret.

GLUMES Glumes persistent; similar; shorter than spikelet. Lower glume ovate; 3–5 mm long; 1 length of upper glume; chartaceous; without keels; 7 -veined. Lower glume apex erose. Upper glume oblong; 3–5 mm long; 0.75–1 length of adjacent fertile lemma; chartaceous; without keels; 7–9 -veined. Upper glume apex erose.

FLORETS Fertile lemma oblong; 4–5 mm long; chartaceous; keeled; 9–13 -veined. Lemma lateral veins ribbed. Lemma apex erose; truncate; mucronate. Palea 1 length of lemma; 2 -veined. Apical sterile florets resembling fertile though underdeveloped.

FLOWER Lodicules 2; cuneate; 0.2 mm long; fleshy; truncate. Anthers 3; 3 mm long. Stigmas 2; sparsely hairy.

FRUIT Caryopsis with adherent pericarp; oblong; laterally compressed; 2–2.5 mm long; dark brown; rugose. Embryo 0.75–1 length of caryopsis.

DISTRIBUTION North America: southwest USA.

NOTES Orcuttieae. Reeder.

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