Coix lacryma-jobi*

Coix lacryma-jobi* Linn. Sp. Pl. 972 (1753).

Classification. (GPWG 2001) : Subfamily Panicoideae. Andropogoneae.

Type of Basionym or Protologue Information: LT: India (LINN-1098.1). LT designated by Clayton & Renvoize, Fl. Trop. E. Afr. Gramineae (3): 857 (1982). ST: van Royen s.n., (L).

Key references (books and floras): [1952] C.A.Gardner, Flora of Western Australia 1 Gramineae (358), [1969] E.E.Henty, Manual Grasses New Guinea (53 as C. lachryma-jobi), [2008] S.W.L.Jacobs, R.D.B.Walley & D.J.B.Wheeler, Grasses of New South Wales (188).

Illustrations: [1983] J.C.Tothill & J.B.Hacker, Grasses of Southern Queensland (168), [2008] S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th edn (188).

Habit. Annual. Culms stature robust to moderate, 90–250 cm tall. Leaves cauline. Ligule an eciliate membrane. Leaf-blades linear or lanceolate, 10–50 cm long, 25–50 mm wide.

Inflorescence. Inflorescence compound, a panicle of rames. Rhachis obsolete.

Spikelets. Spikelets sessile, 1 in the cluster. Companion spikelets pedicelled, 2 in the cluster. Male spikelets 2 in a cluster. Companion spikelets represented by barren pedicels. Fertile spikelets 2-flowered, the lower floret barren (rarely male), the upper fertile, comprising 1 basal sterile florets, comprising 1 fertile floret(s), without rachilla extension, ovate, dorsally compressed, 7–9 mm long.

Glumes. Glumes dissimilar, similar to fertile lemma in texture. Lower glume orbicular, membranous, firmer above, without keels. Upper glume ovate, membranous, keeled, 1-keeled, 11 -nerved. Florets. Basal sterile florets 1, barren, without significant palea. Lemma of lower sterile floret 100 % of length of spikelet, membranous, firmer above, 7 -nerved. Fertile florets female.

Fertile lemma 6–7.6 mm long, keeled, 3–5 -nerved. Palea 2 -nerved, without keels. Lodicules absent or vestigial (female) or present (male). Anthers 3.

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

Australian Distribution: Western Australia, Queensland, New South Wales.

Western Australia: Drummond. Queensland: Cook. New South Wales: North Coast, Central Coast.

Notes. Native from India to Polynesia including some Torres Strait Is.; introduced to mainland Australia as an ornamental and has the potential to become naturalised.

AVH 2011


Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith