Common name
Saltwater Couch

Derivation
Paspalum L., Syst. Nat. 10th edn, 855 (1759); from the Greek paspalos (a kind of millet).

vaginatum- from the Latin vagina (sheath) and -ata (possessing). Inflorescences concealed or partially concealed in uppermost leaf-sheaths.

Published in
Prodr. Veg. Ind. Occ. 21 (1788).

Common synonyms
Paspalum distichum auct. non L.

Habit
Perennial, mat forming. Cataphylls present. Stolons present. Culms erect or decumbent, 8–60 cm tall, 5–13-noded. Mid-culm nodes glabrous. Lateral branches sparsely branched. Leaf-sheaths glabrous on surface. Leaf-sheaths outer margin glabrous or hairy. Leaf-sheath auricles absent. Ligule an eciliate membrane, 0.5–1.2 mm long. Leaf-blades flat or convolute, 2.5–22 cm long, 1–8 mm wide. Leaf-blade surface smooth, glabrous.

Inflorescence
Inflorescence digitate, a panicle of racemes. Racemes 2(–5), spreading, unilateral, 1.5–7.5 cm long, bearing 16–32 fertile spikelets on each. Central inflorescence axis 0–1.2 cm long. Rhachis narrowly winged, angular, 1–2 mm wide. Spikelet packing abaxial, regular, 2-rowed.

Spikelets
Spikelets solitary. Pedicels 0.2–0.6 mm long. Fertile spikelets 2-flowered, comprising 1 fertile floret, lower floret sterile, upper fertile, without rhachilla extension, elliptic or ovate, dorsally compressed, compressed strongly, plano-convex, acute, 2.5–4.5 mm long, falling entire.

Glumes
Glumes both absent or obscure or two (rarely), thinner than fertile lemma. Lower glume when present ovate, 10–20% of length of spikelet, hyaline, 0-nerved. Upper glume elliptic, 2.5–3.7 mm long, 100% of length of spikelet, membranous, 2–6-nerved, midnerve absent. Upper glume surface glabrous. Upper glume margins eciliate. Upper glume apex acute.

Florets
Basal sterile florets 1, without significant palea. Lemma of lower sterile floret similar to upper glume, elliptic, 2.5–3.7 mm long, 100% of length of spikelet, membranous, 2–5-nerved, acute or acuminate. Fertile lemma ovate, 2.3–2.5 mm long, indurate, pallid or yellow. Lemma margins involute. Lemma apex acute. Palea involute, cartilaginous or indurate. Anthers 1.2–1.6 mm long.

Continental Distribution:
Europe, Africa, Temperate Asia, Tropical Asia, Australasia, Pacific, North America, South America.

Australian Distribution:
Western Australia, Northern Territory, South Australia, Queensland, New South Wales, Victoria.

Western Australia: Canning, Irwin, Drummond, Dale, Menzies. Northern Territory: Darwin & Gulf, Central Australia South. South Australia: Eyre Peninsula, Murray, Yorke Peninsula, Southern Lofty, South-eastern. Queensland: Cook, Burke, North Kennedy, South Kennedy, Port Curtis, Burnett, Wide Bay, Moreton. New South Wales: North Coast, Central Coast, South Coast. Victoria: Gippsland Plains, East Gippsland.

Classification. (GPWG 2001):
Panicoideae: Paniceae

Notes
Introduced. Flowers sporadically throughout the year.